{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T18:05:44Z","timestamp":1792087544550,"version":"4.4.0"},"reference-count":249,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T00:00:00Z","timestamp":1738800000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund (FWF)","doi-asserted-by":"publisher","award":["10.55776\/P32777"],"award-info":[{"award-number":["10.55776\/P32777"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund (FWF)","doi-asserted-by":"publisher","award":["10.55776\/P36596"],"award-info":[{"award-number":["10.55776\/P36596"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Reptiles, birds, mammals and amphibians, together forming the clade tetrapods, have a large diversity of cornified skin appendages, such as scales, feathers, hair and claws. The skin appendages consist of dead epithelial cells that are tightly packed with specific structural proteins. Here, we review the molecular diversity and expression patterns of major types of skin appendage proteins, namely keratin intermediate filament proteins, keratin-associated proteins (KRTAPs) and proteins encoded by genes of the epidermal differentiation complex (EDC), including corneous beta-proteins, also known as beta-keratins. We summarize the current knowledge about the components of skin appendages with a focus on keratins and EDC proteins that have recently been identified in reptiles and birds. We discuss gaps of knowledge and suggest directions of future research.<\/jats:p>","DOI":"10.3390\/ani15030457","type":"journal-article","created":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T09:54:38Z","timestamp":1738835678000},"page":"457","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Skin Appendage Proteins of Tetrapods: Building Blocks of Claws, Feathers, Hair and Other Cornified Epithelial Structures"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0687-2024","authenticated-orcid":false,"given":"Karin Brigit","family":"Holthaus","sequence":"first","affiliation":[{"name":"Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-4208-9455","authenticated-orcid":false,"given":"Julia","family":"Steinbinder","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1447-9254","authenticated-orcid":false,"given":"Attila Placido","family":"Sachslehner","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5645-2036","authenticated-orcid":false,"given":"Leopold","family":"Eckhart","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Yenmi\u015f, M., and Ayaz, D. (2023). The story of the finest armor: Developmental aspects of reptile skin. J. Dev. Biol., 11.","DOI":"10.3390\/jdb11010005"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1387\/ijdb.15272390","article-title":"Evo-Devo of amniote integuments and appendages","volume":"48","author":"Wu","year":"2004","journal-title":"Int. J. Dev. Biol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3543","DOI":"10.1002\/ar.24908","article-title":"Comparison of vertebrate skin structure at class level: A review","volume":"305","author":"Akat","year":"2022","journal-title":"Anat. Rec."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Sokolov, V.E. (1982). Mammal Skin, University of California Press.","DOI":"10.1525\/9780520315921"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/j.semcdb.2007.02.005","article-title":"Mammary glands and feathers: Comparing two skin appendages which help define novel classes during vertebrate evolution","volume":"18","author":"Widelitz","year":"2007","journal-title":"Semin. Cell Dev. Biol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1212","DOI":"10.1016\/j.cell.2014.08.019","article-title":"SnapShot: Branching morphogenesis","volume":"158","author":"Chuong","year":"2014","journal-title":"Cell"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1223","DOI":"10.1016\/j.jid.2023.11.018","article-title":"Stabilization of epithelial \u03b2-catenin compromises mammary cell fate acquisition and branching morphogenesis","volume":"144","author":"Satta","year":"2024","journal-title":"J. Investig. Dermatol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1038\/emm.1999.2","article-title":"Bricks and mortar of the epidermal barrier","volume":"31","author":"Nemes","year":"1999","journal-title":"Exp. Mol. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1038\/nrm1619","article-title":"The cornified envelope: A model of cell death in the skin","volume":"6","author":"Candi","year":"2005","journal-title":"Nat. Rev. Mol. Cell Biol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3471","DOI":"10.1016\/j.bbamcr.2013.06.010","article-title":"Cell death by cornification","volume":"1833","author":"Eckhart","year":"2013","journal-title":"Biochim. Biophys. Acta"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1002\/jez.b.23","article-title":"Development and evolution of the amniote integument: Current landscape and future horizon","volume":"298","author":"Chuong","year":"2003","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1093\/intimm\/dxv013","article-title":"Dissecting the formation, structure and barrier function of the stratum corneum","volume":"27","author":"Matsui","year":"2015","journal-title":"Int. Immunol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1242\/jeb.02007","article-title":"Water relations of tetrapod integument","volume":"209","author":"Lillywhite","year":"2006","journal-title":"J. Exp. Biol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1016\/bs.ircmb.2016.06.005","article-title":"The Process of Cornification Evolved from the Initial Keratinization in the Epidermis and Epidermal Derivatives of Vertebrates: A New Synthesis and the Case of Sauropsids","volume":"327","author":"Alibardi","year":"2016","journal-title":"Int. Rev. Cell Mol. Biol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1034\/j.1600-0625.2003.00069.x","article-title":"Mammalian skin evolution: A reevaluation","volume":"12","author":"Maderson","year":"2003","journal-title":"Exp. Dermatol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1002\/jez.b.31","article-title":"Horse hooves and bird feathers: Two model systems for studying the structure and development of highly adapted integumentary accessory organs--the role of the dermo-epidermal interface for the micro-architecture of complex epidermal structures","volume":"298","author":"Bragulla","year":"2003","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1111\/j.1469-7580.2008.01041.x","article-title":"A new scenario for the evolutionary origin of hair, feather, and avian scales","volume":"214","author":"Dhouailly","year":"2009","journal-title":"J. Anat."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"449","DOI":"10.1016\/S0959-437X(00)00111-8","article-title":"Evo-devo of feathers and scales: Building complex epithelial appendages","volume":"10","author":"Chuong","year":"2000","journal-title":"Curr. Opin. Genet. Dev."},{"key":"ref_19","first-page":"513","article-title":"The development of the sauropsid integument: A contribution to the problem of the origin and evolution of feathers","volume":"40","author":"Maderson","year":"2000","journal-title":"Am. Zool."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1146\/annurev-animal-022513-114127","article-title":"Development, regeneration, and evolution of feathers","volume":"3","author":"Chen","year":"2015","journal-title":"Annu. Rev. Anim. Biosci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1348","DOI":"10.1111\/j.0022-202X.2004.22611.x","article-title":"Sculpting skin appendages out of epidermal layers via temporally and spatially regulated apoptotic events","volume":"122","author":"Chang","year":"2004","journal-title":"J. Investig. Dermatol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"R132","DOI":"10.1016\/j.cub.2008.12.005","article-title":"The hair follicle as a dynamic miniorgan","volume":"19","author":"Schneider","year":"2009","journal-title":"Curr. Biol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1126\/science.1201647","article-title":"Self-organizing and stochastic behaviors during the regeneration of hair stem cells","volume":"332","author":"Plikus","year":"2011","journal-title":"Science"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"917","DOI":"10.1016\/j.semcdb.2012.08.011","article-title":"Mesenchymal-epithelial interactions during hair follicle morphogenesis and cycling","volume":"23","author":"Sennett","year":"2012","journal-title":"Semin. Cell Dev. Biol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1093\/molbev\/msx295","article-title":"Multiple regulatory modules are required for scale-to-feather conversion","volume":"35","author":"Wu","year":"2018","journal-title":"Mol. Biol. Evol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Cruz, C.F., Costa, C., Gomes, A.C., Matam\u00e1, T., and Cavaco-Paulo, A. (2016). Human Hair and the Impact of Cosmetic Procedures: A Review on Cleansing and Shape-Modulating Cosmetics. Cosmetics, 3.","DOI":"10.3390\/cosmetics3030026"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1709","DOI":"10.1007\/s00709-020-01544-7","article-title":"Detection of endogenous lipids in chicken feathers distinct from preen gland constituents","volume":"257","author":"Kirfel","year":"2020","journal-title":"Protoplasma"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1002\/(SICI)1097-4687(199601)227:1<1::AID-JMOR1>3.0.CO;2-F","article-title":"Ultrastructural organization of avian stratum corneum lipids as the basis for facultative cutaneous waterproofing","volume":"227","author":"Menon","year":"1996","journal-title":"J. Morphol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1063","DOI":"10.1111\/j.1600-0625.2008.00786.x","article-title":"The skin: An indispensable barrier","volume":"17","author":"Proksch","year":"2008","journal-title":"Exp. Dermatol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"760","DOI":"10.1016\/j.jid.2018.11.005","article-title":"Mutations in Recessive Congenital Ichthyoses Illuminate the Origin and Functions of the Corneocyte Lipid Envelope","volume":"139","author":"Crumrine","year":"2019","journal-title":"J. Investig. Dermatol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1016\/j.zool.2011.10.004","article-title":"The shift from aquatic to terrestrial phenotype in Lissotriton italicus: Larval and adult remodelling of the skin","volume":"115","author":"Perrotta","year":"2012","journal-title":"Zoology"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1080\/11250000903173395","article-title":"Cornification in the claw of the amphibian Xenopus laevis (Pipidae, Anura) and comparison with claws in amniotes","volume":"77","author":"Alibardi","year":"2010","journal-title":"Ital. J. Zool."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1111\/j.1469-7580.2009.01052.x","article-title":"The anatomy and development of the claws of Xenopus laevis (Lissamphibia: Anura) reveal alternate pathways of structural evolution in the integument of tetrapods","volume":"214","author":"Maddin","year":"2009","journal-title":"J. Anat."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1002\/ar.1091820402","article-title":"Development of beaks of Rana pipiens larvae","volume":"182","author":"Kaung","year":"1975","journal-title":"Anat. Rec."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1002\/jmor.1051950107","article-title":"Morphology of the oral disc of Bufo bufo (Salientia: Bufonidae) tadpoles","volume":"195","author":"Marinelli","year":"1988","journal-title":"J. Morphol."},{"key":"ref_36","first-page":"51","article-title":"Cornification of the beak of Rana dalmatina tadpoles suggests the presence of basic keratin-associated proteins","volume":"49","author":"Alibardi","year":"2010","journal-title":"Zool. Stud."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1002\/jmor.20016","article-title":"Structural diversity of nuptial pads in Phyllomedusinae (Amphibia: Anura: Hylidae)","volume":"273","author":"Luna","year":"2012","journal-title":"J. Morphol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/0012-1606(75)90087-1","article-title":"The developmental cytology of the nuptial pad in the red-spotted newt","volume":"46","author":"Forbes","year":"1975","journal-title":"Dev. Biol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"5551","DOI":"10.1038\/s41467-019-13531-5","article-title":"Genomic and transcriptomic insights into molecular basis of sexually dimorphic nuptial spines in Leptobrachium leishanense","volume":"10","author":"Li","year":"2019","journal-title":"Nat. Commun."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.proghi.2006.01.001","article-title":"Cytochemical, biochemical and molecular aspects of the process of keratinization in the epidermis of reptilian scales","volume":"40","author":"Alibardi","year":"2006","journal-title":"Prog. Histochem. Cytochem."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1002\/(SICI)1097-4687(199804)236:1<1::AID-JMOR1>3.0.CO;2-B","article-title":"Ultrastructural contributions to an understanding of the cellular mechanisms involved in lizard skin shedding with comments on the function and evolution of a unique Lepidosaurian phenomenon","volume":"236","author":"Maderson","year":"1998","journal-title":"J. Morphol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1002\/jez.1401740211","article-title":"Morphological and biophysical identification of fibrous proteins in the amniote epidermis","volume":"174","author":"Baden","year":"1970","journal-title":"J. Exp. Zool."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Bereiter-Hahn, J., Matoltsy, A.G., and Sylvia-Richards, K. (1986). The skin of Reptiles: Epidermis and dermis. Biology of the Integument, Volume 2 Vertebrates, Springer.","DOI":"10.1007\/978-3-662-00989-5"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"961","DOI":"10.1111\/j.1600-0625.2007.00609.x","article-title":"Review. Hard keratins in reptilian epidermis in comparison to those of birds and mammals","volume":"16","author":"Alibardi","year":"2007","journal-title":"Exp. Dermatol."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"813","DOI":"10.1387\/ijdb.072556cc","article-title":"Reptile scale paradigm: Evo-Devo, pattern formation and regeneration","volume":"53","author":"Chang","year":"2009","journal-title":"Int. J. Dev. Biol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1002\/jmor.1096","article-title":"History and function of scale microornamentation in lacertid lizards","volume":"252","author":"Arnold","year":"2002","journal-title":"J. Morphol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"770","DOI":"10.2108\/zsj.29.770","article-title":"Scales microstructure of snakes from the Egyptian area","volume":"29","author":"Allam","year":"2012","journal-title":"Zool. Sci."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1407","DOI":"10.1007\/s00709-023-01860-8","article-title":"Micro-ornamentation patterns in different areas of the epidermis in the gecko Tarentola mauritanica reflect variations in the accumulation of corneous material in Oberhautchen cells","volume":"260","author":"Bonfitto","year":"2023","journal-title":"Protoplasma"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1111\/j.1469-7580.2008.01043.x","article-title":"The integumentary skeleton of tetrapods: Origin, evolution, and development","volume":"214","author":"Vickaryous","year":"2009","journal-title":"J. Anat."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/brv.12788","article-title":"A review of the osteoderms of lizards (Reptilia: Squamata)","volume":"97","author":"Williams","year":"2022","journal-title":"Biol. Rev. Camb. Philos. Soc."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1016\/j.zool.2005.11.005","article-title":"Skin structure and cornification proteins in the soft-shelled turtle Trionyx spiniferus","volume":"109","author":"Alibardi","year":"2006","journal-title":"Zoology"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.ympev.2014.10.021","article-title":"A phylogenomic analysis of turtles","volume":"83","author":"Crawford","year":"2015","journal-title":"Mol. Phylogenet. Evol."},{"key":"ref_53","first-page":"123","article-title":"Why does a trait evolve multiple times within a clade? Repeated evolution of snakelike body form in squamate reptiles","volume":"60","author":"Wiens","year":"2006","journal-title":"Evolution"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"2703","DOI":"10.1002\/ar.24604","article-title":"Development, structure, and protein composition of the corneous beak in turtles","volume":"304","author":"Alibardi","year":"2021","journal-title":"Anat. Rec."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.proghi.2008.01.001","article-title":"Cytochemical and molecular characteristics of the process of cornification during feather morphogenesis","volume":"43","author":"Alibardi","year":"2008","journal-title":"Prog. Histochem. Cytochem."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"570","DOI":"10.1002\/jez.b.21073","article-title":"Evolution of the morphological innovations of feathers","volume":"304","author":"Prum","year":"2005","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"1409","DOI":"10.1016\/j.cell.2019.11.008","article-title":"The making of a flight feather: Bio-architectural principles and adaptation","volume":"179","author":"Chang","year":"2019","journal-title":"Cell"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1166","DOI":"10.1002\/jmor.10747","article-title":"Towards a comprehensive model of feather regeneration","volume":"270","author":"Maderson","year":"2009","journal-title":"J. Morphol."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1038\/nature01196","article-title":"The morphogenesis of feathers","volume":"420","author":"Yu","year":"2002","journal-title":"Nature"},{"key":"ref_60","first-page":"461","article-title":"The Integumentary Morphology of Modern Birds\u2014An Overview","volume":"40","author":"Stettenheim","year":"2000","journal-title":"Am. Zool."},{"key":"ref_61","first-page":"530","article-title":"The expression of beta keratins in the epidermal appendages of reptiles and birds","volume":"40","author":"Sawyer","year":"2000","journal-title":"Am. Zool."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1002\/jez.b.26","article-title":"Avian skin development and the evolutionary origin of feathers","volume":"298","author":"Sawyer","year":"2003","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_63","doi-asserted-by":"crossref","unstructured":"Wu, P., Lai, Y.C., Widelitz, R., and Chuong, C.M. (2018). Comprehensive molecular and cellular studies suggest avian scutate scales are secondarily derived from feathers, and more distant from reptilian scales. Sci. Rep., 8.","DOI":"10.1038\/s41598-018-35176-y"},{"key":"ref_64","doi-asserted-by":"crossref","unstructured":"Liu, T.Y., Hughes, M.W., Wang, H.V., Yang, W.C., Chuong, C.M., and Wu, P. (2023). Molecular and cellular characterization of avian Reticulate scales implies the Evo-Devo novelty of skin appendages in Foot Sole. J. Dev. Biol., 11.","DOI":"10.3390\/jdb11030030"},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"1300","DOI":"10.1093\/oxfordjournals.molbev.a026220","article-title":"Phylogenetic relationships of the enigmatic hoatzin (Opisthocomus hoazin) resolved using mitochondrial and nuclear gene sequences","volume":"16","author":"Hughes","year":"1999","journal-title":"Mol. Biol. Evol."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1007\/978-981-10-8195-8_10","article-title":"Development of hair fibres","volume":"1054","author":"Harland","year":"2018","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0074-7696(05)43001-6","article-title":"Keratins of the human hair follicle","volume":"243","author":"Langbein","year":"2005","journal-title":"Int. Rev. Cytol."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1387\/ijdb.15272381","article-title":"Hair follicle differentiation and regulation","volume":"48","author":"Rogers","year":"2004","journal-title":"Int. J. Dev. Biol."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.cels.2016.08.010","article-title":"Single-cell transcriptomics reveals that differentiation and spatial signatures shape epidermal and hair follicle heterogeneity","volume":"3","author":"Joost","year":"2016","journal-title":"Cell Syst."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.ydbio.2024.07.002","article-title":"Cell differentiation in the embryonic periderm and in scaffolding epithelia of skin appendages","volume":"515","author":"Eckhart","year":"2024","journal-title":"Dev. Biol."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1034\/j.1600-0625.2001.100601.x","article-title":"Mutant laboratory mice with abnormalities in hair follicle morphogenesis, cycling, and\/or structure: Annotated tables","volume":"10","author":"Nakamura","year":"2001","journal-title":"Exp. Dermatol."},{"key":"ref_72","first-page":"159","article-title":"What is the \u2018true\u2019 function of skin?","volume":"11","author":"Chuong","year":"2002","journal-title":"Exp. Dermatol."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"1327","DOI":"10.1002\/ar.23163","article-title":"Sensory hairs in the bowhead whale, Balaena mysticetus (Cetacea, Mammalia)","volume":"298","author":"Drake","year":"2015","journal-title":"Anat. Rec."},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1007\/BF00190140","article-title":"Unmyelinated innervation of sinus hair follicles in rats","volume":"188","author":"Waite","year":"1993","journal-title":"Anat. Embryol."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"1638","DOI":"10.1016\/j.jid.2023.04.015","article-title":"Studying hair growth cycle and its effects on mouse skin","volume":"143","author":"Wang","year":"2023","journal-title":"J. Investig. Dermatol."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"761","DOI":"10.1002\/ar.23081","article-title":"Observations on fur development in echidna (Monotremata, Mammalia) indicate that spines precede hairs in ontogeny","volume":"298","author":"Alibardi","year":"2015","journal-title":"Anat. Rec."},{"key":"ref_77","doi-asserted-by":"crossref","unstructured":"Li, H.M., Yang, B.Z., Zhang, X.J., Jiang, H.Y., Li, L.M., Ahmad, H.I., and Chen, J.P. (2020). Transcriptome analysis reveals the genetic basis underlying the development of skin appendages and immunity in hedgehog (Atelerix albiventris). Sci. Rep., 10.","DOI":"10.1038\/s41598-020-70844-y"},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"713","DOI":"10.1016\/j.jmbbm.2010.12.013","article-title":"Armadillo armor: Mechanical testing and micro-structural evaluation","volume":"4","author":"Chen","year":"2011","journal-title":"J. Mech. Behav. Biomed. Mater."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.actbio.2016.05.028","article-title":"Pangolin armor: Overlapping, structure, and mechanical properties of the keratinous scales","volume":"41","author":"Wang","year":"2016","journal-title":"Acta Biomater."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.stemcr.2013.04.001","article-title":"The interfollicular epidermis of adult mouse tail comprises two distinct cell lineages that are differentially regulated by Wnt, Edaradd, and Lrig1","volume":"1","author":"Gomez","year":"2013","journal-title":"Stem Cell Rep."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"1172","DOI":"10.1002\/jmor.10465","article-title":"Structure of white rhinoceros (Ceratotherium simum) horn investigated by X-ray computed tomography and histology with implications for growth and external form","volume":"267","author":"Hieronymus","year":"2006","journal-title":"J. Morphol."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"3992","DOI":"10.1016\/j.cub.2018.10.047","article-title":"Tooth loss precedes the origin of baleen in whales","volume":"28","author":"Peredo","year":"2018","journal-title":"Curr. Biol."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"2124","DOI":"10.1016\/j.cub.2021.02.057","article-title":"Genomic and anatomical comparisons of skin support independent adaptation to life in water by cetaceans and hippos","volume":"31","author":"Springer","year":"2021","journal-title":"Curr. Biol."},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1016\/S0092-8674(03)00273-3","article-title":"Desmoglein 4 in hair follicle differentiation and epidermal adhesion: Evidence from inherited hypotrichosis and acquired pemphigus vulgaris","volume":"113","author":"Kljuic","year":"2003","journal-title":"Cell"},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1111\/j.1432-0436.2006.00061.x","article-title":"Desmoglein 4 is expressed in highly differentiated keratinocytes and trichocytes in human epidermis and hair follicle","volume":"74","author":"Bazzi","year":"2006","journal-title":"Differentiation"},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"771","DOI":"10.1021\/pr301036k","article-title":"Chicken corneocyte cross-linked proteome","volume":"12","author":"Rice","year":"2013","journal-title":"J. Proteome Res."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"R535","DOI":"10.1016\/j.cub.2020.03.047","article-title":"Tracing the evolutionary origin of desmosomes","volume":"30","author":"Green","year":"2020","journal-title":"Curr. Biol."},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"cs261899","DOI":"10.1242\/jcs.261899","article-title":"Desmosomes at a glance","volume":"137","author":"Perl","year":"2024","journal-title":"J. Cell Sci."},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1007\/s10495-018-1505-4","article-title":"Cornification of nail keratinocytes requires autophagy for bulk degradation of intracellular proteins while sparing components of the cytoskeleton","volume":"24","author":"Jaeger","year":"2019","journal-title":"Apoptosis"},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1016\/j.jid.2023.06.199","article-title":"Autophagy controls the protein composition of hair shafts","volume":"144","author":"Sukseree","year":"2024","journal-title":"J. Investig. Dermatol."},{"key":"ref_91","doi-asserted-by":"crossref","unstructured":"Eckhart, L., Gruber, F., and Sukseree, S. (2024). Autophagy-mediated cellular remodeling during terminal differentiation of keratinocytes in the epidermis and skin appendages. Cells, 13.","DOI":"10.3390\/cells13201675"},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1016\/j.ejcb.2005.01.007","article-title":"Terrestrial vertebrates have two keratin gene clusters; striking differences in teleost fish","volume":"84","author":"Zimek","year":"2005","journal-title":"Eur. J. Cell Biol."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"995","DOI":"10.1093\/molbev\/msr269","article-title":"Radiation and functional diversification of alpha keratins during early vertebrate evolution","volume":"29","author":"Vandebergh","year":"2012","journal-title":"Mol. Biol. Evol."},{"key":"ref_94","doi-asserted-by":"crossref","first-page":"982","DOI":"10.1093\/molbev\/msz279","article-title":"Convergent evolution of cysteine-rich keratins in hard skin appendages of terrestrial vertebrates","volume":"37","author":"Ehrlich","year":"2020","journal-title":"Mol. Biol. Evol."},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"989","DOI":"10.1111\/1523-1747.ep12338501","article-title":"Genes encoding structural proteins of epidermal cornification and S100 calcium-binding proteins form a gene complex (\u201cepidermal differentiation complex\u201d) on human chromosome 1q21","volume":"106","author":"Mischke","year":"1996","journal-title":"J. Investig. Dermatol."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"15481","DOI":"10.1073\/pnas.0807643105","article-title":"Ancient origin of the gene encoding involucrin, a precursor of the cross-linked envelope of epidermis and related epithelia","volume":"105","author":"Vanhoutteghem","year":"2008","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"1453","DOI":"10.1093\/hmg\/ddq019","article-title":"A milieu of regulatory elements in the epidermal differentiation complex syntenic block: Implications for atopic dermatitis and psoriasis","volume":"19","author":"Conlan","year":"2010","journal-title":"Hum. Mol. Genet."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"3194","DOI":"10.1093\/molbev\/msu251","article-title":"Evolutionary origin and diversification of epidermal barrier proteins in amniotes","volume":"31","author":"Strasser","year":"2014","journal-title":"Mol. Biol. Evol."},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1111\/exd.13317","article-title":"Filaggrin has evolved from an \u201cS100 fused-type protein\u201d (SFTP) gene present in a common ancestor of amphibians and mammals","volume":"26","author":"Mlitz","year":"2017","journal-title":"Exp. Dermatol."},{"key":"ref_100","doi-asserted-by":"crossref","unstructured":"Sachslehner, A.P., and Eckhart, L. (2022). Evolutionary diversification of epidermal barrier genes in amphibians. Sci. Rep., 12.","DOI":"10.1038\/s41598-022-18053-7"},{"key":"ref_101","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1002\/jez.10145","article-title":"Immunocytochemical analysis of beta keratins in the epidermis of chelonians, lepidosaurians, and archosaurians","volume":"293","author":"Alibardi","year":"2002","journal-title":"J. Exp. Zool."},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1002\/jez.b.21242","article-title":"Analysis of gene expression in gecko digital adhesive pads indicates significant production of cysteine- and glycine-rich beta-keratins","volume":"312","author":"Hallahan","year":"2009","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_103","doi-asserted-by":"crossref","unstructured":"Greenwold, M.J., and Sawyer, R.H. (2010). Genomic organization and molecular phylogenies of the beta (beta) keratin multigene family in the chicken (Gallus gallus) and zebra finch (Taeniopygia guttata): Implications for feather evolution. BMC Evol. Biol., 10.","DOI":"10.1186\/1471-2148-10-148"},{"key":"ref_104","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1002\/jez.b.22514","article-title":"Molecular evolution and expression of archosaurian \u03b2-keratins: Diversification and expansion of archosaurian \u03b2-keratins and the origin of feather \u03b2-keratins","volume":"320","author":"Greenwold","year":"2013","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_105","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.ydbio.2023.05.007","article-title":"General aspects on skin development in vertebrates with emphasis on sauropsids epidermis","volume":"501","author":"Alibardi","year":"2023","journal-title":"Dev. Biol."},{"key":"ref_106","doi-asserted-by":"crossref","unstructured":"Parry, D.A.D., and Winter, D.J. (2021). Keratin intermediate filament chains in tuatara (Sphenodon punctatus): A comparison of tuatara and human sequences. J. Struct. Biol., 213.","DOI":"10.1016\/j.jsb.2021.107706"},{"key":"ref_107","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1016\/j.jsb.2006.03.018","article-title":"Human hair keratin-associated proteins: Sequence regularities and structural implications","volume":"155","author":"Parry","year":"2006","journal-title":"J. Struct. Biol."},{"key":"ref_108","doi-asserted-by":"crossref","first-page":"19440","DOI":"10.1074\/jbc.M100657200","article-title":"Characterization of a cluster of human high\/ultrahigh sulfur keratin-associated protein genes embedded in the type I keratin gene domain on chromosome 17q12-21","volume":"276","author":"Rogers","year":"2001","journal-title":"J. Biol. Chem."},{"key":"ref_109","doi-asserted-by":"crossref","first-page":"48993","DOI":"10.1074\/jbc.M206422200","article-title":"Characterization of a first domain of human high glycine-tyrosine and high sulfur keratin-associated protein (KAP) genes on chromosome 21q22.1","volume":"277","author":"Rogers","year":"2002","journal-title":"J. Biol. Chem."},{"key":"ref_110","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1016\/S0074-7696(06)51006-X","article-title":"Human hair keratin-associated proteins (KAPs)","volume":"251","author":"Rogers","year":"2006","journal-title":"Int. Rev. Cytol."},{"key":"ref_111","doi-asserted-by":"crossref","unstructured":"Wu, D.D., Irwin, D.M., and Zhang, Y.P. (2008). Molecular evolution of the keratin associated protein gene family in mammals, role in the evolution of mammalian hair. BMC Evol. Biol., 8.","DOI":"10.1186\/1471-2148-8-241"},{"key":"ref_112","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1007\/978-981-10-8195-8_5","article-title":"Evolution of Trichocyte Keratin Associated Proteins","volume":"1054","author":"Wu","year":"2018","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_113","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/S0955-0674(01)00301-5","article-title":"\u2018Hard\u2019 and \u2018soft\u2019 principles defining the structure, function and regulation of keratin intermediate filaments","volume":"14","author":"Coulombe","year":"2002","journal-title":"Curr. Opin. Cell Biol."},{"key":"ref_114","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1083\/jcb.200603161","article-title":"New consensus nomenclature for mammalian keratins","volume":"174","author":"Schweizer","year":"2006","journal-title":"J. Cell Biol."},{"key":"ref_115","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.ceb.2014.12.009","article-title":"Evolutionary aspects in intermediate filament proteins","volume":"32","author":"Peter","year":"2015","journal-title":"Curr. Opin. Cell Biol."},{"key":"ref_116","doi-asserted-by":"crossref","first-page":"516","DOI":"10.1111\/j.1469-7580.2009.01066.x","article-title":"Structure and functions of keratin proteins in simple, stratified, keratinized and cornified epithelia","volume":"214","author":"Bragulla","year":"2009","journal-title":"J. Anat."},{"key":"ref_117","doi-asserted-by":"crossref","unstructured":"Jacob, J.T., Coulombe, P.A., Kwan, R., and Omary, M.B. (2018). Types I and II keratin intermediate filaments. Cold Spring Harb. Perspect. Biol., 10.","DOI":"10.1101\/cshperspect.a018275"},{"key":"ref_118","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1006\/excr.1995.1326","article-title":"Sequence data and chromosomal localization of human type I and type II hair keratin genes","volume":"220","author":"Rogers","year":"1995","journal-title":"Exp. Cell Res."},{"key":"ref_119","doi-asserted-by":"crossref","first-page":"26683","DOI":"10.1074\/jbc.273.41.26683","article-title":"Characterization of a 190-kilobase pair domain of human type I hair keratin genes","volume":"273","author":"Rogers","year":"1998","journal-title":"J. Biol. Chem."},{"key":"ref_120","doi-asserted-by":"crossref","first-page":"464","DOI":"10.1046\/j.1523-1747.2000.00910.x","article-title":"Characterization of a 300 kbp region of human DNA containing the type II hair keratin gene domain","volume":"114","author":"Rogers","year":"2000","journal-title":"J. Investig. Dermatol."},{"key":"ref_121","doi-asserted-by":"crossref","first-page":"1459","DOI":"10.1083\/jcb.151.7.1459","article-title":"In vitro assembly and structure of trichocyte keratin intermediate filaments: A novel role for stabilization by disulfide bonding","volume":"151","author":"Wang","year":"2000","journal-title":"J. Cell Biol."},{"key":"ref_122","doi-asserted-by":"crossref","first-page":"512","DOI":"10.1046\/j.1523-1747.2003.12087.x","article-title":"K6irs1, K6irs2, K6irs3, and K6irs4 represent the inner-root-sheath-specific type II epithelial keratins of the human hair follicle","volume":"120","author":"Langbein","year":"2003","journal-title":"J. Investig. Dermatol."},{"key":"ref_123","doi-asserted-by":"crossref","first-page":"2377","DOI":"10.1038\/sj.jid.5700494","article-title":"K25 (K25irs1), K26 (K25irs2), K27 (K25irs3), and K28 (K25irs4) represent the type I inner root sheath keratins of the human hair follicle","volume":"126","author":"Langbein","year":"2006","journal-title":"J. Investig. Dermatol."},{"key":"ref_124","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1111\/j.1365-2133.2004.06108.x","article-title":"Expression of hair keratins in the adult nail unit: An immunohistochemical analysis of the onychogenesis in the proximal nail fold, matrix and nail bed","volume":"151","author":"Perrin","year":"2004","journal-title":"Br. J. Dermatol."},{"key":"ref_125","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1007\/s00418-008-0435-6","article-title":"The human keratins: Biology and pathology","volume":"129","author":"Moll","year":"2008","journal-title":"Histochem. Cell Biol."},{"key":"ref_126","doi-asserted-by":"crossref","first-page":"2106","DOI":"10.1002\/rcm.8285","article-title":"Identification of rhinoceros keratin using direct analysis in real time time-of-flight mass spectrometry and multivariate statistical analysis","volume":"32","author":"Price","year":"2018","journal-title":"Rapid Commun. Mass Spectrom."},{"key":"ref_127","doi-asserted-by":"crossref","unstructured":"Solazzo, C., Fitzhugh, W., Kaplan, S., Potter, C., and Dyer, J.M. (2017). Molecular markers in keratins from Mysticeti whales for species identification of baleen in museum and archaeological collections. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0183053"},{"key":"ref_128","first-page":"2597","article-title":"Calcification provides mechanical reinforcement to whale baleen alpha-keratin","volume":"277","author":"Szewciw","year":"2010","journal-title":"Proc. Biol. Sci."},{"key":"ref_129","doi-asserted-by":"crossref","first-page":"1532","DOI":"10.1038\/sj.jid.5700734","article-title":"Novel type I hair keratins K39 and K40 are the last to be expressed in differentiation of the hair: Completion of the human hair keratin catalog","volume":"127","author":"Langbein","year":"2007","journal-title":"J. Investig. Dermatol."},{"key":"ref_130","doi-asserted-by":"crossref","first-page":"527","DOI":"10.1111\/j.1432-0436.2004.07209006.x","article-title":"The human type I keratin gene family: Characterization of new hair follicle specific members and evaluation of the chromosome 17q21.2 gene domain","volume":"72","author":"Rogers","year":"2004","journal-title":"Differentiation"},{"key":"ref_131","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1007\/978-981-10-8195-8_4","article-title":"Evolution of trichocyte keratins","volume":"1054","author":"Eckhart","year":"2018","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_132","doi-asserted-by":"crossref","first-page":"3146","DOI":"10.1016\/j.jid.2022.06.022","article-title":"Comparative spatial transcriptomic and single-cell analyses of human nail units and hair follicles show transcriptional similarities between the onychodermis and follicular dermal papilla","volume":"142","author":"Shim","year":"2022","journal-title":"J. Investig. Dermatol."},{"key":"ref_133","doi-asserted-by":"crossref","unstructured":"Greenwold, M.J., Bao, W., Jarvis, E.D., Hu, H., Li, C., Gilbert, M.T., Zhang, G., and Sawyer, R.H. (2014). Dynamic evolution of the alpha (\u03b1) and beta (\u03b2) keratins has accompanied integument diversification and the adaptation of birds into novel lifestyles. BMC Evol. Biol., 14.","DOI":"10.1186\/s12862-014-0249-1"},{"key":"ref_134","doi-asserted-by":"crossref","unstructured":"Ng, C.S., Wu, P., Foley, J., Foley, A., McDonald, M.L., Juan, W.T., Huang, C.J., Lai, Y.T., Lo, W.S., and Chen, C.F. (2012). The chicken frizzle feather is due to an \u03b1-keratin (KRT75) mutation that causes a defective rachis. PLoS Genet., 8.","DOI":"10.1371\/journal.pgen.1002748"},{"key":"ref_135","doi-asserted-by":"crossref","first-page":"2258","DOI":"10.1093\/gbe\/evu181","article-title":"Genomic organization, transcriptomic analysis, and functional characterization of avian \u03b1- and \u03b2-keratins in diverse feather forms","volume":"6","author":"Ng","year":"2014","journal-title":"Genome Biol. Evol."},{"key":"ref_136","doi-asserted-by":"crossref","first-page":"E6770","DOI":"10.1073\/pnas.1520566112","article-title":"Topographical mapping of \u03b1- and \u03b2-keratins on developing chicken skin integuments: Functional interaction and evolutionary perspectives","volume":"112","author":"Wu","year":"2015","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_137","doi-asserted-by":"crossref","first-page":"18419","DOI":"10.1073\/pnas.0805154105","article-title":"Identification of reptilian genes encoding hair keratin-like proteins suggests a new scenario for the evolutionary origin of hair","volume":"105","author":"Eckhart","year":"2008","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_138","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1002\/jmor.10920","article-title":"Ultrastructural localization of hair keratin homologs in the claw of the lizard Anolis carolinensis","volume":"272","author":"Alibardi","year":"2011","journal-title":"J. Morphol."},{"key":"ref_139","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1007\/s00239-010-9427-y","article-title":"Deleterious mutations of a claw keratin in multiple taxa of reptiles","volume":"72","author":"Benato","year":"2011","journal-title":"J. Mol. Evol."},{"key":"ref_140","doi-asserted-by":"crossref","unstructured":"Holthaus, K.B., Steinbinder, J., Sachslehner, A.P., and Eckhart, L. (2025). Convergent evolution has led to the loss of claw proteins in snakes and worm lizards. Genome Biol. Evol., 17.","DOI":"10.1093\/gbe\/evae274"},{"key":"ref_141","doi-asserted-by":"crossref","unstructured":"Lachner, J., Ehrlich, F., Wielscher, M., Farlik, M., Hermann, M., Tschachler, E., and Eckhart, L. (2022). Single-cell transcriptomics defines keratinocyte differentiation in avian scutate scales. Sci. Rep., 12.","DOI":"10.1038\/s41598-021-04082-1"},{"key":"ref_142","doi-asserted-by":"crossref","first-page":"8766","DOI":"10.1016\/S0021-9258(19)38954-9","article-title":"The two-chain coiled-coil molecule of native epidermal keratin intermediate filaments is a type I-type II heterodimer","volume":"265","author":"Steinert","year":"1990","journal-title":"J. Biol. Chem."},{"key":"ref_143","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1083\/jcb.111.1.153","article-title":"Elucidating the early stages of keratin filament assembly","volume":"111","author":"Coulombe","year":"1990","journal-title":"J. Cell Biol."},{"key":"ref_144","doi-asserted-by":"crossref","first-page":"378","DOI":"10.2307\/1543118","article-title":"Protein\u2013protein interactions in intermediate filament structure and anchorage to the cell surface","volume":"194","author":"Meng","year":"1998","journal-title":"Biol. Bull."},{"key":"ref_145","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1242\/jcs.104.3.727","article-title":"Suprabasal change and subsequent formation of disulfide-stabilized homo- and heterodimers of keratins during esophageal epithelial differentiation","volume":"104","author":"Pang","year":"1993","journal-title":"J. Cell Sci."},{"key":"ref_146","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.1083\/jcb.97.4.1131","article-title":"The fibrillar substructure of keratin filaments unraveled","volume":"97","author":"Aebi","year":"1983","journal-title":"J. Cell. Biol."},{"key":"ref_147","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/S1040-0486(01)70013-0","article-title":"Keratins: Dynamic, flexible structural proteins of epithelial cells","volume":"54","author":"Steinert","year":"2001","journal-title":"Curr. Probl. Dermatol."},{"key":"ref_148","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1006\/jsbi.2002.4466","article-title":"Characterization of early assembly intermediates of recombinant human keratins","volume":"137","author":"Herrmann","year":"2002","journal-title":"J. Struct. Biol."},{"key":"ref_149","doi-asserted-by":"crossref","unstructured":"Bray, D.J., Walsh, T.R., Noro, M.G., and Notman, R. (2015). Complete structure of an epithelial keratin dimer: Implications for intermediate filament assembly. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0132706"},{"key":"ref_150","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1159\/000070842","article-title":"Molecular skin barrier models and some central problems for the understanding of skin barrier structure and function","volume":"16","author":"Norlen","year":"2003","journal-title":"Ski. Pharmacol. Appl. Ski. Physiol."},{"key":"ref_151","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1007\/978-981-10-8195-8_12","article-title":"Crosslinking Between Trichocyte Keratins and Keratin Associated Proteins","volume":"1054","year":"2018","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_152","doi-asserted-by":"crossref","unstructured":"Parry, D.A.D., and Winter, D.J. (2021). Keratin intermediate filament chains in the European common wall lizard (Podarcis muralis) and a potential keratin filament crosslinker. J. Struct. Biol., 213.","DOI":"10.1016\/j.jsb.2021.107793"},{"key":"ref_153","doi-asserted-by":"crossref","first-page":"51524","DOI":"10.1074\/jbc.M404331200","article-title":"Krtap16, characterization of a new hair keratin-associated protein (KAP) gene complex on mouse chromosome 16 and evidence for regulation by Hoxc13","volume":"279","author":"Pruett","year":"2004","journal-title":"J. Biol. Chem."},{"key":"ref_154","doi-asserted-by":"crossref","first-page":"3377","DOI":"10.1021\/pr0702619","article-title":"Hard (Beta-)keratins in the epidermis of reptiles: Composition, sequence, and molecular organization","volume":"6","author":"Toni","year":"2007","journal-title":"J. Proteome Res."},{"key":"ref_155","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1007\/978-3-319-49674-0_8","article-title":"Filamentous structure of hard \u03b2-keratins in the epidermal appendages of birds and reptiles","volume":"82","author":"Fraser","year":"2017","journal-title":"Subcell. Biochem."},{"key":"ref_156","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1002\/jez.b.22840","article-title":"Review: Evolution and diversification of corneous beta-proteins, the characteristic epidermal proteins of reptiles and birds","volume":"330","author":"Holthaus","year":"2018","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_157","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1016\/0006-3002(47)90170-4","article-title":"X-ray studies of the distribution of protein chain types in the vertebrate epidermis","volume":"1","author":"Rudall","year":"1947","journal-title":"Biochim. Biophys. Acta"},{"key":"ref_158","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1016\/0141-8130(96)01129-4","article-title":"The molecular structure of reptilian keratin","volume":"19","author":"Fraser","year":"1996","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_159","doi-asserted-by":"crossref","first-page":"338","DOI":"10.1002\/jez.b.22689","article-title":"Sauropsid cornification is based on corneous beta-proteins, a special type of proteins of the epidermis","volume":"326B","author":"Alibardi","year":"2016","journal-title":"J. Exp. Zool."},{"key":"ref_160","doi-asserted-by":"crossref","first-page":"923","DOI":"10.1093\/gbe\/evt060","article-title":"Rapid evolution of Beta-keratin genes contribute to phenotypic differences that distinguish turtles and birds from other reptiles","volume":"5","author":"Li","year":"2013","journal-title":"Genome Biol. Evol."},{"key":"ref_161","doi-asserted-by":"crossref","first-page":"726","DOI":"10.1093\/molbev\/msv265","article-title":"Comparative genomics identifies epidermal proteins associated with the evolution of the turtle shell","volume":"33","author":"Holthaus","year":"2016","journal-title":"Mol. Biol. Evol."},{"key":"ref_162","doi-asserted-by":"crossref","first-page":"391","DOI":"10.1016\/j.jsb.2010.09.020","article-title":"The structural basis of the filament-matrix texture in the avian\/reptilian group of hard \u03b2-keratins","volume":"173","author":"Fraser","year":"2011","journal-title":"J. Struct. Biol."},{"key":"ref_163","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1016\/0022-2836(89)90593-7","article-title":"Avian keratin genes. I. A molecular analysis of the structure and expression of a group of feather keratin genes","volume":"209","author":"Presland","year":"1989","journal-title":"J. Mol. Biol."},{"key":"ref_164","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1016\/0022-2836(89)90594-9","article-title":"Avian keratin genes. II. Chromosomal arrangement and close linkage of three gene families","volume":"209","author":"Presland","year":"1989","journal-title":"J. Mol. Biol."},{"key":"ref_165","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1016\/0378-1119(91)90415-8","article-title":"The structure and expression of a gene encoding chick claw keratin","volume":"101","author":"Whitbread","year":"1991","journal-title":"Gene"},{"key":"ref_166","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1111\/j.1432-0436.2004.07204002.x","article-title":"Serial cultivation of chicken keratinocytes, a composite cell type that accumulates lipids and synthesizes a novel \u03b2-keratin","volume":"72","author":"Vanhoutteghem","year":"2004","journal-title":"Differentiation"},{"key":"ref_167","doi-asserted-by":"crossref","first-page":"282","DOI":"10.1016\/j.jsb.2016.03.004","article-title":"The molecular organization of the beta-sheet region in corneous beta-proteins (beta-keratins) of sauropsids explains its stability and polymerization into filaments","volume":"194","author":"Calvaresi","year":"2016","journal-title":"J. Struct. Biol."},{"key":"ref_168","doi-asserted-by":"crossref","first-page":"5477","DOI":"10.1021\/ja3088407","article-title":"The supramolecular chemistry of \u03b2-sheets","volume":"135","author":"Cheng","year":"2013","journal-title":"J. Am. Chem. Soc."},{"key":"ref_169","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1007\/s12551-008-0005-0","article-title":"The role of b-sheets in the structure and assembly of keratins","volume":"1","author":"Fraser","year":"2009","journal-title":"Biophys. Rev."},{"key":"ref_170","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jsb.2008.01.011","article-title":"Molecular packing in the feather keratin filament","volume":"162","author":"Fraser","year":"2008","journal-title":"J. Struct. Biol."},{"key":"ref_171","doi-asserted-by":"crossref","unstructured":"Fraser, R.D.B., and Parry, D.A.D. (2020). Lepidosaur \u00df-keratin chains with four 34-residue repeats: Modelling reveals a potential filament-crosslinking role. J. Struct. Biol., 209.","DOI":"10.1016\/j.jsb.2019.107413"},{"key":"ref_172","first-page":"11","article-title":"Forty keratin-associated beta-proteins (beta-keratins) form the hard layers of scales, claws, and adhesive pads in the green anole lizard, Anolis carolinensis","volume":"314","author":"Nardi","year":"2010","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_173","doi-asserted-by":"crossref","unstructured":"Holthaus, K.B., Mlitz, V., Strasser, B., Tschachler, E., Alibardi, L., and Eckhart, L. (2017). Identification and comparative analysis of the epidermal differentiation complex in snakes. Sci. Rep., 7.","DOI":"10.1038\/srep45338"},{"key":"ref_174","doi-asserted-by":"crossref","unstructured":"Parry, D.A.D. (2020). Structure and topology of the linkers in the conserved lepidosaur \u03b2-keratin chain with four 34-residue repeats support an interfilament role for the central linker. J. Struct. Biol., 212.","DOI":"10.1016\/j.jsb.2020.107599"},{"key":"ref_175","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1111\/j.1600-0625.2012.01472.x","article-title":"The human epidermal differentiation complex: Cornified envelope precursors, S100 proteins and the \u2018fused genes\u2019 family","volume":"21","author":"Kypriotou","year":"2012","journal-title":"Exp. Dermatol."},{"key":"ref_176","doi-asserted-by":"crossref","first-page":"1517","DOI":"10.2741\/4001","article-title":"Update on the epidermal differentiation complex","volume":"17","author":"Henry","year":"2012","journal-title":"Front. Biosci."},{"key":"ref_177","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1016\/0141-8130(91)90037-U","article-title":"Glycine loops in proteins: Their occurrence in certain intermediate filament chains, loricrins and single-stranded RNA binding proteins","volume":"13","author":"Steinert","year":"1991","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_178","doi-asserted-by":"crossref","first-page":"6626","DOI":"10.1016\/S0021-9258(18)38163-8","article-title":"Characterization of human loricrin. Structure and function of a new class of epidermal cell envelope proteins","volume":"266","author":"Hohl","year":"1991","journal-title":"J. Biol. Chem."},{"key":"ref_179","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/j.jsb.2014.10.012","article-title":"Amino acid sequence homologies in the hard keratins of birds and reptiles, and their implications for molecular structure and physical properties","volume":"188","author":"Fraser","year":"2014","journal-title":"J. Struct. Biol."},{"key":"ref_180","doi-asserted-by":"crossref","first-page":"2067","DOI":"10.1073\/pnas.95.5.2067","article-title":"A highly conserved lysine residue on the head domain of type II keratins is essential for the attachment of keratin intermediate filaments to the cornified cell envelope through isopeptide crosslinking by transglutaminases","volume":"95","author":"Candi","year":"1998","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_181","doi-asserted-by":"crossref","first-page":"7226","DOI":"10.1074\/jbc.274.11.7226","article-title":"Transglutaminase cross-linking properties of the small proline-rich 1 family of cornified cell envelope proteins. Integration with loricrin","volume":"274","author":"Candi","year":"1999","journal-title":"J. Biol. Chem."},{"key":"ref_182","doi-asserted-by":"crossref","first-page":"729","DOI":"10.1038\/276729a0","article-title":"Assembly of stratum corneum basic protein and keratin filaments in macrofibrils","volume":"276","author":"Dale","year":"1978","journal-title":"Nature"},{"key":"ref_183","doi-asserted-by":"crossref","first-page":"17702","DOI":"10.1074\/jbc.270.30.17702","article-title":"The proteins elafin, filaggrin, keratin intermediate filaments, loricrin, and small proline-rich proteins 1 and 2 are isodipeptide cross-linked components of the human epidermal cornified cell envelope","volume":"270","author":"Steinert","year":"1995","journal-title":"J. Biol. Chem."},{"key":"ref_184","doi-asserted-by":"crossref","first-page":"41409","DOI":"10.1074\/jbc.M302037200","article-title":"Trichohyalin mechanically strengthens the hair follicle: Multiple cross-bridging roles in the inner root sheath","volume":"278","author":"Steinert","year":"2003","journal-title":"J. Biol. Chem."},{"key":"ref_185","doi-asserted-by":"crossref","first-page":"694","DOI":"10.1093\/gbe\/evy035","article-title":"Comparative analysis of epidermal differentiation genes of crocodilians suggests new models for the evolutionary origin of avian feathers","volume":"10","author":"Holthaus","year":"2018","journal-title":"Genome Biol. Evol."},{"key":"ref_186","doi-asserted-by":"crossref","unstructured":"Holthaus, K.B., Alibardi, L., Tschachler, E., and Eckhart, L. (2020). Identification of epidermal differentiation genes of the tuatara provides insights into the early evolution of lepidosaurian skin. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-69885-0"},{"key":"ref_187","doi-asserted-by":"crossref","unstructured":"Holthaus, K.B., Sachslehner, A.P., Steinbinder, J., and Eckhart, L. (2024). Epidermal differentiation genes of the common wall lizard encode proteins with extremely biased amino acid contents. Genes, 15.","DOI":"10.3390\/genes15091136"},{"key":"ref_188","doi-asserted-by":"crossref","unstructured":"Holthaus, K.B., and Eckhart, L. (2024). Development-associated genes of the epidermal differentiation complex (EDC). J. Dev. Biol., 12.","DOI":"10.3390\/jdb12010004"},{"key":"ref_189","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1046\/j.1365-2133.2000.03246.x","article-title":"Keratin expression in the normal nail unit: Markers of regional differentiation","volume":"142","author":"Wojnarowska","year":"2000","journal-title":"Br. J. Dermatol."},{"key":"ref_190","doi-asserted-by":"crossref","first-page":"543","DOI":"10.1097\/DAD.0b013e318158d741","article-title":"Expression of follicular sheath keratins in the normal nail with special reference to the morphological analysis of the distal nail unit","volume":"29","author":"Perrin","year":"2007","journal-title":"Am. J. Dermatopathol."},{"key":"ref_191","doi-asserted-by":"crossref","first-page":"521","DOI":"10.1002\/ar.22660","article-title":"Comparative anatomy of mouse and human nail units","volume":"296","author":"Fleckman","year":"2013","journal-title":"Anat. Rec."},{"key":"ref_192","doi-asserted-by":"crossref","unstructured":"Vandebergh, W., Maex, M., Bossuyt, F., and Van Bocxlaer, I. (2013). Recurrent functional divergence of early tetrapod keratins in amphibian toe pads and mammalian hair. Biol. Lett., 9.","DOI":"10.1098\/rsbl.2013.0051"},{"key":"ref_193","doi-asserted-by":"crossref","first-page":"2328","DOI":"10.1038\/s41467-024-46373-x","article-title":"Evolutionary origin of Hoxc13-dependent skin appendages in amphibians","volume":"15","author":"Carron","year":"2024","journal-title":"Nat. Commun."},{"key":"ref_194","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1101\/gad.12.1.11","article-title":"Hoxc13 mutant mice lack external hair","volume":"12","author":"Godwin","year":"1998","journal-title":"Genes Dev."},{"key":"ref_195","doi-asserted-by":"crossref","first-page":"3718","DOI":"10.1074\/jbc.M101616200","article-title":"HOXC13 is involved in the regulation of human hair keratin gene expression","volume":"277","author":"Winter","year":"2002","journal-title":"J. Biol. Chem."},{"key":"ref_196","doi-asserted-by":"crossref","first-page":"648","DOI":"10.1002\/ar.23112","article-title":"Eye, nose, hair, and throat: External anatomy of the head of a neonate gray whale (Cetacea, Mysticeti, Eschrichtiidae)","volume":"298","author":"Berta","year":"2015","journal-title":"Anat. Rec."},{"key":"ref_197","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1093\/molbev\/msy214","article-title":"Differential evolution of the epidermal keratin cytoskeleton in terrestrial and aquatic mammals","volume":"36","author":"Ehrlich","year":"2019","journal-title":"Mol. Biol. Evol."},{"key":"ref_198","doi-asserted-by":"crossref","unstructured":"Sachslehner, A.P., Surbek, M., Holthaus, K.B., Steinbinder, J., Golabi, B., Hess, C., and Eckhart, L. (2024). The evolution of transglutaminases underlies the origin and loss of cornified skin appendages in vertebrates. Mol. Biol. Evol., 41.","DOI":"10.1093\/molbev\/msae100"},{"key":"ref_199","doi-asserted-by":"crossref","unstructured":"Armstrong, C., Cassimeris, L., Da Silva Santos, C., Micoogullari, Y., Wagner, B., Babasyan, S., Brooks, S., and Galantino-Homer, H. (2019). The expression of equine keratins K42 and K124 is restricted to the hoof epidermal lamellae of Equus caballus. PLoS ONE, 14.","DOI":"10.1101\/678102"},{"key":"ref_200","doi-asserted-by":"crossref","first-page":"2685","DOI":"10.1038\/jid.2014.204","article-title":"Trichohyalin-like proteins have evolutionarily conserved roles in the morphogenesis of skin appendages","volume":"134","author":"Mlitz","year":"2014","journal-title":"J. Investig. Dermatol."},{"key":"ref_201","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/j.tice.2007.06.004","article-title":"Characterization of keratins and associated proteins involved in the corneification of crocodilian epidermis","volume":"39","author":"Alibardi","year":"2007","journal-title":"Tissue Cell"},{"key":"ref_202","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1002\/jmor.20086","article-title":"Cornification in reptilian epidermis occurs through the deposition of keratin-associated-beta proteins (beta-keratins) onto a scaffold of intermediate filament keratins","volume":"274","author":"Alibardi","year":"2013","journal-title":"J. Morphol."},{"key":"ref_203","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1002\/jez.b.5","article-title":"Origin of feathers: Feather beta (beta) keratins are expressed in discrete epidermal cell populations of embryonic scutate scales","volume":"295","author":"Sawyer","year":"2003","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_204","first-page":"175","article-title":"Beta-keratin localization in developing alligator scales and feathers in relation to the development and evolution of feathers","volume":"38","author":"Alibardi","year":"2006","journal-title":"J. Submicrosc. Cytol. Pathol."},{"key":"ref_205","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1002\/aja.1001960411","article-title":"Region-specific patterns of beta keratin expression during avian skin development","volume":"196","author":"Knapp","year":"1993","journal-title":"Dev. Dyn."},{"key":"ref_206","doi-asserted-by":"crossref","first-page":"374","DOI":"10.1002\/dvdy.21022","article-title":"Cloning and characterization of scale beta-keratins in the differentiating epidermis of geckos show they are glycine-proline-serine-rich proteins with a central motif homologous to avian beta-keratins","volume":"236","author":"Nardi","year":"2007","journal-title":"Dev. Dyn."},{"key":"ref_207","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1007\/s00709-013-0585-9","article-title":"Immunolocalization of alpha-keratins and associated beta-proteins in lizard epidermis shows that acidic keratins mix with basic keratin-associated beta-proteins","volume":"251","author":"Alibardi","year":"2014","journal-title":"Protoplasma"},{"key":"ref_208","doi-asserted-by":"crossref","first-page":"10033","DOI":"10.1038\/ncomms10033","article-title":"Gekko japonicus genome reveals evolution of adhesive toe pads and tail regeneration","volume":"6","author":"Liu","year":"2015","journal-title":"Nat. Communic."},{"key":"ref_209","doi-asserted-by":"crossref","unstructured":"Wang, F., Chen, M., Cai, F., Li, P., Yan, J., and Zhou, K. (2020). Expression of specific corneous beta proteins in the developing digits of the Japanese gecko (Gekko japonicus) reveals their role in the growth of adhesive setae. Comp. Biochem. Physiol. B Biochem. Mol. Biol., 240.","DOI":"10.1016\/j.cbpb.2019.110370"},{"key":"ref_210","doi-asserted-by":"crossref","first-page":"693","DOI":"10.1242\/jcs.107.2.693","article-title":"Protein composition of cornified cell envelopes of epidermal keratinocytes","volume":"107","author":"Steven","year":"1994","journal-title":"J. Cell Sci."},{"key":"ref_211","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1002\/jez.b.22610","article-title":"Immunolocalization of loricrin in the maturing \u03b1-layer of normal and regenerating epidermis of the lizard Anolis carolinensis","volume":"324","author":"Alibardi","year":"2015","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_212","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/j.aanat.2012.08.005","article-title":"Immunolocalization of alpha-keratins and feather beta proteins in feather cells and comparison with the general process of cornification in the skin of mammals","volume":"195","author":"Alibardi","year":"2013","journal-title":"Ann. Anat."},{"key":"ref_213","doi-asserted-by":"crossref","first-page":"1257","DOI":"10.1007\/s00709-019-01381-3","article-title":"Immunolocalization and phylogenetic profiling of the feather protein with the highest cysteine content","volume":"256","author":"Lachner","year":"2019","journal-title":"Protoplasma"},{"key":"ref_214","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.micron.2013.07.002","article-title":"Ultrastructural immunolocalization of alpha-keratins and associated beta-proteins (beta-keratins) suggests a new interpretation on the process of hard and soft cornification in turtle epidermis","volume":"52\u201353","author":"Alibardi","year":"2013","journal-title":"Micron"},{"key":"ref_215","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1002\/jez.1402710408","article-title":"Histidine-rich protein B of embryonic feathers is present in the transient embryonic layers of scutate scales","volume":"271","author":"Barnes","year":"1995","journal-title":"J. Exp. Zool."},{"key":"ref_216","doi-asserted-by":"crossref","unstructured":"Alibardi, L., Holthaus, K.B., Sukseree, S., Hermann, M., Tschachler, E., and Eckhart, L. (2016). Immunolocalization of a histidine-rich epidermal differentiation protein in the chicken supports the hypothesis of an evolutionary developmental link between the embryonic subperiderm and feather barbs and barbules. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0167789"},{"key":"ref_217","doi-asserted-by":"crossref","first-page":"917","DOI":"10.1002\/jmor.21357","article-title":"Immunolocalization of epidermal differentiation complex proteins reveals distinct molecular compositions of cells that control structure and mechanical properties of avian skin appendages","volume":"282","author":"Alibardi","year":"2021","journal-title":"J. Morphol."},{"key":"ref_218","doi-asserted-by":"crossref","unstructured":"Strasser, B., Mlitz, V., Hermann, M., Tschachler, E., and Eckhart, L. (2015). Convergent evolution of cysteine-rich proteins in feathers and hair. BMC Evol. Biol., 15.","DOI":"10.1186\/s12862-015-0360-y"},{"key":"ref_219","first-page":"59","article-title":"The role of keratin proteins and their genes in the growth, structure and properties of hair","volume":"78","author":"Powell","year":"1997","journal-title":"EXS"},{"key":"ref_220","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1007\/978-981-10-8195-8_3","article-title":"Diversity of trichocyte keratins and keratin associated proteins","volume":"1054","author":"Plowman","year":"2018","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_221","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1078\/0944-2006-00048","article-title":"Immunocytochemical observations on the cornification of soft and hard epidermis in the turtle Chrysemys picta","volume":"105","author":"Alibardi","year":"2002","journal-title":"Zoology"},{"key":"ref_222","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1002\/jmor.10337","article-title":"Proliferation in the epidermis of chelonians and growth of the horny scutes","volume":"265","author":"Alibardi","year":"2005","journal-title":"J. Morphol."},{"key":"ref_223","doi-asserted-by":"crossref","first-page":"104","DOI":"10.2460\/ajvr.2001.62.104","article-title":"Soluble scute proteins of healthy and ill desert tortoises (Gopherus agassizii)","volume":"62","author":"Homer","year":"2001","journal-title":"Am. J. Vet. Res."},{"key":"ref_224","doi-asserted-by":"crossref","first-page":"201857","DOI":"10.1098\/rsos.201857","article-title":"Creation of a peptide database of corneous beta-proteins of marine turtles for the identification of tortoiseshell: Archaeological combs as case study","volume":"8","author":"Solazzo","year":"2021","journal-title":"R. Soc. Open Sci."},{"key":"ref_225","doi-asserted-by":"crossref","first-page":"284","DOI":"10.1111\/j.1469-7580.2008.01030.x","article-title":"Beta-keratins of turtle shell are glycine-proline-tyrosine-rich proteins similar to those of crocodilians and birds","volume":"214","author":"Nardi","year":"2009","journal-title":"J. Anat."},{"key":"ref_226","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1002\/jez.1402600215","article-title":"Region-specific expression of scutate scale type beta keratins in the developing chick beak","volume":"260","author":"Shames","year":"1991","journal-title":"J. Exp. Zool."},{"key":"ref_227","first-page":"229","article-title":"Proteomic analysis of hair shaft and nail plate","volume":"62","author":"Rice","year":"2011","journal-title":"J. Cosmet. Sci."},{"key":"ref_228","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1038\/jid.2009.192","article-title":"The keratins of the human beard hair medulla: The riddle in the middle","volume":"130","author":"Langbein","year":"2010","journal-title":"J. Investig. Dermatol."},{"key":"ref_229","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1007\/s004390000439","article-title":"Human type I hair keratin pseudogene phihHaA has functional orthologs in the chimpanzee and gorilla: Evidence for recent inactivation of the human gene after the Pan-Homo divergence","volume":"108","author":"Winter","year":"2001","journal-title":"Hum. Genet."},{"key":"ref_230","doi-asserted-by":"crossref","first-page":"1282","DOI":"10.1039\/b604537p","article-title":"Hair\u2014The most sophisticated biological composite material","volume":"36","author":"Popescu","year":"2007","journal-title":"Chem. Soc. Rev."},{"key":"ref_231","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1007\/978-981-10-8195-8_7","article-title":"Trichocyte keratin associated proteins (KAPs)","volume":"1054","author":"Fraser","year":"2018","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_232","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1046\/j.1432-0436.1995.5830227.x","article-title":"Characterization of a gene encoding a cysteine-rich keratin associated protein synthesized late in rabbit hair follicle differentiation","volume":"58","author":"Powell","year":"1995","journal-title":"Differentiation"},{"key":"ref_233","doi-asserted-by":"crossref","unstructured":"Khan, I., Maldonado, E., Vasconcelos, V., O\u2019Brien, S.J., Johnson, W.E., and Antunes, A. (2014). Mammalian keratin associated proteins (KRTAPs) subgenomes: Disentangling hair diversity and adaptation to terrestrial and aquatic environments. BMC Genom., 15.","DOI":"10.1186\/1471-2164-15-779"},{"key":"ref_234","doi-asserted-by":"crossref","unstructured":"Zhou, H., Gong, H., Wang, J., Dyer, J.M., Luo, Y., and Hickford, J.G.H. (2016). Identification of four new gene members of the KAP6 gene family in sheep. Sci. Rep., 6.","DOI":"10.1038\/srep24074"},{"key":"ref_235","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.jdermsci.2011.12.014","article-title":"Identification of the C-terminal tail domain of AHF\/trichohyalin as the critical site for modulation of the keratin filamentous meshwork in the keratinocyte","volume":"65","author":"Takase","year":"2012","journal-title":"J. Dermatol. Sci."},{"key":"ref_236","doi-asserted-by":"crossref","first-page":"1419","DOI":"10.1083\/jcb.102.4.1419","article-title":"Trichohyalin, an intermediate filament-associated protein of the hair follicle","volume":"102","author":"Rothnagel","year":"1986","journal-title":"J. Cell Biol."},{"key":"ref_237","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1016\/j.aanat.2011.10.012","article-title":"Ultrastructural immunolocalization of involucrin in the medulla and inner root sheath of the human hair","volume":"194","author":"Alibardi","year":"2012","journal-title":"Ann. Anat."},{"key":"ref_238","doi-asserted-by":"crossref","first-page":"752","DOI":"10.1046\/j.0022-202x.2001.01488.x","article-title":"Inquiry into the role of skin sulfhydryl oxidase in epidermal disulfide bond formation: Implications of the localization and regulation of skin SOx as revealed by TPA, retinoic acid, and UVB radiation","volume":"117","author":"Hashimoto","year":"2001","journal-title":"J. Investig. Dermatol."},{"key":"ref_239","doi-asserted-by":"crossref","first-page":"2053","DOI":"10.1016\/S0021-9258(19)62353-7","article-title":"Keratin filaments of cultured human epidermal cells. Formation of intermolecular disulfide bonds during terminal differentiation","volume":"253","author":"Sun","year":"1978","journal-title":"J. Biol. Chem."},{"key":"ref_240","doi-asserted-by":"crossref","first-page":"708","DOI":"10.1002\/prot.26053","article-title":"A detailed mapping of the readily accessible disulphide bonds in the cortex of wool fibres","volume":"89","author":"Plowman","year":"2021","journal-title":"Proteins"},{"key":"ref_241","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1002\/ar.24705","article-title":"Vertebrate keratinization evolved into cornification mainly due to transglutaminase and sulfhydryl oxidase activities on epidermal proteins: An immunohistochemical survey","volume":"305","author":"Alibardi","year":"2022","journal-title":"Anat. Rec."},{"key":"ref_242","doi-asserted-by":"crossref","first-page":"481","DOI":"10.1111\/j.0022-202X.2005.23627.x","article-title":"Transglutaminase function in epidermis","volume":"124","author":"Eckert","year":"2005","journal-title":"J. Investig. Dermatol."},{"key":"ref_243","doi-asserted-by":"crossref","first-page":"789","DOI":"10.1002\/bies.10144","article-title":"Epithelial barrier function: Assembly and structural features of the cornified cell envelope","volume":"24","author":"Kalinin","year":"2002","journal-title":"Bioessays"},{"key":"ref_244","doi-asserted-by":"crossref","first-page":"33066","DOI":"10.1074\/jbc.M102553200","article-title":"Evolution of transglutaminase genes: Identification of a transglutaminase gene cluster on human chromosome 15q15. Structure of the gene encoding transglutaminase X and a novel gene family member, transglutaminase Z","volume":"276","author":"Grenard","year":"2001","journal-title":"J. Biol. Chem."},{"key":"ref_245","doi-asserted-by":"crossref","first-page":"16012","DOI":"10.1016\/S0021-9258(17)36359-7","article-title":"Catalytic properties of a calmodulin-regulated transglutaminase from human platelet and chicken gizzard","volume":"260","author":"Puszkin","year":"1985","journal-title":"J. Biol. Chem."},{"key":"ref_246","doi-asserted-by":"crossref","first-page":"526","DOI":"10.1002\/jez.b.21016","article-title":"Immuno-cross reactivity of transglutaminase and cornification marker proteins in the epidermis of vertebrates suggests common processes of soft cornification across species","volume":"302","author":"Alibardi","year":"2004","journal-title":"J. Exp. Zool. B Mol. Dev. Evol."},{"key":"ref_247","doi-asserted-by":"crossref","unstructured":"Sachslehner, A.P., Surbek, M., Golabi, B., Geiselhofer, M., J\u00e4ger, K., Hess, C., Kuchler, U., Gruber, R., and Eckhart, L. (2023). Transglutaminase activity is conserved in stratified epithelia and skin appendages of mammals and birds. Int. J. Mol. Sci., 24.","DOI":"10.3390\/ijms24032193"},{"key":"ref_248","first-page":"e65580","article-title":"Using avian skin explants to study tissue patterning and organogenesis","volume":"15","author":"Jiang","year":"2023","journal-title":"J. Vis. Exp."},{"key":"ref_249","doi-asserted-by":"crossref","first-page":"102798","DOI":"10.1016\/j.isci.2021.102798","article-title":"Engineering with keratin: A functional material and a source of bioinspiration","volume":"24","author":"Lazarus","year":"2021","journal-title":"iScience"}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/15\/3\/457\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:28:16Z","timestamp":1760027296000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/15\/3\/457"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,6]]},"references-count":249,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["ani15030457"],"URL":"https:\/\/doi.org\/10.3390\/ani15030457","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,6]]}}}