{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T04:05:02Z","timestamp":1780718702117,"version":"3.54.1"},"reference-count":49,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T00:00:00Z","timestamp":1673568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute of Health","award":["P41 GM103533"],"award-info":[{"award-number":["P41 GM103533"]}]},{"name":"University of Colorado Anschutz","award":["P41 GM103533"],"award-info":[{"award-number":["P41 GM103533"]}]},{"name":"University of Northern Colorado","award":["P41 GM103533"],"award-info":[{"award-number":["P41 GM103533"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>The Crotalus intermedius group is a clade of rattlesnakes consisting of several species adapted to a high elevation habitat, primarily in M\u00e9xico. Crotalus tancitarensis was previously classified as C. intermedius, until individuals occurring on Cerro Tanc\u00edtaro in Michoac\u00e1n, M\u00e9xico, were reevaluated and classified as a new species (C. tancitarensis) based on scale pattern and geographic location. This study aimed to characterize the venom of C. tancitarensis and compare the venom profile to those of other species within the Crotalus intermedius group using gel electrophoresis, biochemical assays, reverse-phase high performance liquid chromatography, mass spectrometry, and lethal toxicity (LD50) assays. Results show that the venom profiles of species within the Crotalus intermedius group are similar, but with distinct differences in phospholipase A2 (PLA2), metalloproteinase PI (SVMP PI), and kallikrein-like serine proteinase (SVSP) activity and relative abundance. Proteomic analysis indicated that the highland forms produce venoms with 50\u201360 protein isoforms and a composition typical of type I rattlesnake venoms (abundant SVMPs, lack of presynaptic PLA2-based neurotoxins), as well as a diversity of typical Crotalus venom components such as serine proteinases, PLA2s, C-type lectins, and less abundant toxins (LAAOs, CRiSPs, etc.). The overall venom profile of C. tancitarensis appears most similar to C. transversus, which is consistent with a previous mitochondrial DNA analysis of the Crotalus intermedius group. These rattlesnakes of the Mexican highlands represent a radiation of high elevation specialists, and in spite of divergence of species in these Sky Island habitats, venom composition of species analyzed here has remained relatively conserved. The majority of protein family isoforms are conserved in all members of the clade, and as seen in other more broadly distributed rattlesnake species, differences in their venoms are largely due to relative concentrations of specific components.<\/jats:p>","DOI":"10.3390\/toxins15010072","type":"journal-article","created":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T04:02:04Z","timestamp":1673582524000},"page":"72","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Montane Rattlesnakes in M\u00e9xico: Venoms of Crotalus tancitarensis and Related Species within the Crotalus intermedius Group"],"prefix":"10.3390","volume":"15","author":[{"given":"Emily R.","family":"Grabowsky","sequence":"first","affiliation":[{"name":"School of Biological Sciences, University of Northern Colorado, Greeley, CO 80639, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6890-512X","authenticated-orcid":false,"given":"Anthony J.","family":"Saviola","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA"},{"name":"Department of Molecular Medicine and Neurobiology, The Scripps Research Institute, La Jolla, CA 92037, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javier","family":"Alvarado-D\u00edaz","sequence":"additional","affiliation":[{"name":"INIRENA (Instituto de Investigaciones sobre los Recursos Naturales), Morelia CP 58330, Michoac\u00e1n, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adrian Quijada","family":"Mascare\u00f1as","sequence":"additional","affiliation":[{"name":"Biology Department, Tohono O\u2019odham Community College, Tucson, AZ 85634, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kirk C.","family":"Hansen","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"suffix":"III","given":"John R.","family":"Yates","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Neurobiology, The Scripps Research Institute, La Jolla, CA 92037, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4515-2545","authenticated-orcid":false,"given":"Stephen P.","family":"Mackessy","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, University of Northern Colorado, Greeley, CO 80639, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,13]]},"reference":[{"key":"ref_1","unstructured":"Uetz, P., Freed, P., Aguilar, R., and Ho\u0161ek, J. 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