{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T16:33:57Z","timestamp":1787243637976,"version":"build-2736575974"},"reference-count":57,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,10,26]],"date-time":"2021-10-26T00:00:00Z","timestamp":1635206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Viroids are small infectious pathogens, composed of a short single-stranded circular RNA. Hop (Humulus lupulus L.) plants are hosts to four viroids from the family Pospiviroidae. Hop latent viroid (HLVd) is spread worldwide in all hop-growing regions without any visible symptoms on infected hop plants. In this study, we evaluated the influence of HLVd infection on the content and the composition of secondary metabolites in maturated hop cones, together with gene expression analyses of involved biosynthesis and regulation genes for Saaz, Sl\u00e1dek, Premiant and Agnus cultivars. We confirmed that the contents of alpha bitter acids were significantly reduced in the range from 8.8% to 34% by viroid infection. New, we found that viroid infection significantly reduced the contents of xanthohumol in the range from 3.9% to 23.5%. In essential oils of Saaz cultivar, the contents of monoterpenes, terpene epoxides and terpene alcohols were increased, but the contents of sesquiterpenes and terpene ketones were decreased. Secondary metabolites changes were supported by gene expression analyses, except essential oils. Last-step biosynthesis enzyme genes, namely humulone synthase 1 (HS1) and 2 (HS2) for alpha bitter acids and O-methytransferase 1 (OMT1) for xanthohumol, were down-regulated by viroid infection. We found that the expression of ribosomal protein L5 (RPL5) RPL5 and the splicing of transcription factor IIIA-7ZF were affected by viroid infection and a disbalance in proteosynthesis can influence transcriptions of biosynthesis and regulatory genes involved in of secondary metabolites biosynthesis. We suppose that RPL5\/TFIIIA-7ZF regulatory cascade can be involved in HLVd replication as for other viroids of the family Pospiviroidae.<\/jats:p>","DOI":"10.3390\/plants10112297","type":"journal-article","created":{"date-parts":[[2021,10,26]],"date-time":"2021-10-26T23:54:33Z","timestamp":1635292473000},"page":"2297","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["The Influence of Hop Latent Viroid (HLVd) Infection on Gene Expression and Secondary Metabolite Contents in Hop (Humulus lupulus L.) Glandular Trichomes"],"prefix":"10.3390","volume":"10","author":[{"given":"Josef","family":"Patzak","sequence":"first","affiliation":[{"name":"Hop Research Institute Co., Ltd., Kada\u0148sk\u00e1 2525, 438 01 \u017datec, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alena","family":"Henychov\u00e1","sequence":"additional","affiliation":[{"name":"Hop Research Institute Co., Ltd., Kada\u0148sk\u00e1 2525, 438 01 \u017datec, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karel","family":"Krofta","sequence":"additional","affiliation":[{"name":"Hop Research Institute Co., Ltd., Kada\u0148sk\u00e1 2525, 438 01 \u017datec, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petr","family":"Svoboda","sequence":"additional","affiliation":[{"name":"Hop Research Institute Co., Ltd., Kada\u0148sk\u00e1 2525, 438 01 \u017datec, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivana","family":"Mal\u00ed\u0159ov\u00e1","sequence":"additional","affiliation":[{"name":"Hop Research Institute Co., Ltd., Kada\u0148sk\u00e1 2525, 438 01 \u017datec, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,26]]},"reference":[{"key":"ref_1","unstructured":"Hadidi, A., Flores, R., Randles, J.W., and Palukaitis, P. (2017). Viroids and Sattelites, Academic Press."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"324","DOI":"10.1094\/PDIS-92-3-0324","article-title":"Viruses and viroid infected hop: Epidemiology and management","volume":"92","author":"Pethybridge","year":"2008","journal-title":"Plant Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1007\/s10327-004-0105-z","article-title":"Characterization of a new viroid strain from hops: Evidence for viroid speciation by isolation in different host species","volume":"70","author":"Sano","year":"2004","journal-title":"J. Gen. Plant Pathol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"592","DOI":"10.1094\/PDIS-08-11-0640-PDN","article-title":"First report of Hop stunt viroid infecting hop in Slovenia","volume":"96","author":"Majer","year":"2012","journal-title":"Plant Dis."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1094\/PDIS-06-16-0884-RE","article-title":"Hop stunt viroid: Effects on vegetative growth and yield of hop cultivars, and its cistribution in Central Washington state","volume":"101","author":"Kappagantu","year":"2017","journal-title":"Plant Dis."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Clark, S.M., Vaitheeswaran, V., Ambrose, S.J., Purves, R.W., and Page, J.E. (2013). Transcriptome analysis of bitter acid biosynthesis and precursor pathways in hop (Humulus lupulus). BMC Plant Biol., 13.","DOI":"10.1186\/1471-2229-13-12"},{"key":"ref_7","unstructured":"Radi\u0161ek, S., Oset, M., \u010cerenak, A., Jak\u0161e, J., Knapi\u010d, V., Matou\u0161ek, J., and Javornik, B. (2013, January 4\u20139). Research activities focused on hop viroid diseases in Slovenia. Proceedings of the Scientific Commission of IHGC, Kiev, Ukraine."},{"key":"ref_8","unstructured":"Radi\u0161ek, S. (August, January 30). Management of hop viroid diseases in Slovenia. Proceedings of the 56th International Hop Growers\u2019 Convention (IHGC) Congress, Yakima, WA, USA."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"579","DOI":"10.1023\/A:1013798821676","article-title":"Hop latent viroid (HLVd)-caused pathogenesis: Effects of HLVd infection on lupulin composition of meristem culture-derived hop (Humulus lupulus L.)","volume":"44","author":"Patzak","year":"2001","journal-title":"Biol. Plant."},{"key":"ref_10","unstructured":"Seigner, E., Haugg, B., Hager, P., Enders, R., Kneidl, J., Lutz, A., Seigner, L., Einberger, K., Absmeier, C., and Keckel, L. (2019, January 7\u201311). Realtime PCR based diagnostics and meristem culture\u2014Essential tools for healthy hops. Proceedings of the Scientific Commission of IHGC, Bischoffsheim, France."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1111\/j.1744-7348.1990.tb04222.x","article-title":"Some effects of hop latent viroid on two cultivars of hop (Humulus lupulus) in the UK","volume":"117","author":"Barbara","year":"1990","journal-title":"Ann. Appl. Biol."},{"key":"ref_12","first-page":"126","article-title":"Effects of hop latent viroid on weight and quality of the cones of the hop cultivar Wye challenger","volume":"118","author":"Adams","year":"1991","journal-title":"Ann. Appl. Biol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1111\/j.1744-7348.1992.tb03468.x","article-title":"The distribution and spread of hop latent viroid within two commercial plantings of hop (Humulus lupulus)","volume":"121","author":"Adams","year":"1992","journal-title":"Ann. Appl. Biol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"653","DOI":"10.1016\/j.indcrop.2018.08.009","article-title":"Aroma profile and bitter acid characterization of hop cones (Humulus lupulus L.) of five healthy and infected Polish cultivars","volume":"124","author":"Pistelli","year":"2018","journal-title":"Ind. Crops Prod."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"489","DOI":"10.1016\/S0308-8146(02)00114-0","article-title":"Determination and verification of hop varieties by analysis of essential oils","volume":"77","year":"2002","journal-title":"Food Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1271\/bbb.65.150","article-title":"Cloning and analysis of valerophenone synthase gene expressed specifically in lupulin gland of hop (Humulus lupulus L.)","volume":"65","author":"Okada","year":"2001","journal-title":"Biosci. Biotechnol. Biochem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1301","DOI":"10.1093\/mp\/sst004","article-title":"Characterization of the formation of branched short-chain fatty acid:CoAs for bitter acid biosynthesis in hop glandular trichomes","volume":"6","author":"Xu","year":"2013","journal-title":"Mol. Plant"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.1271\/bbb.110228","article-title":"The biosynthesis of isoprenoids and the mechanisms regulating it in plants","volume":"75","author":"Okada","year":"2011","journal-title":"Biosci. Biotechnol. Biochem."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"199","DOI":"10.5511\/plantbiotechnology.27.199","article-title":"An aromatic prenyltransferase-like gene HlPT-1 preferentially expressed in lupulin glands of hop","volume":"27","author":"Tsurumaru","year":"2010","journal-title":"Plant Biotechnol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1016\/j.bbrc.2011.11.125","article-title":"HlPT-1, a membrane-bound prenyltransferase responsible for the biosynthesis of bitter acids in hops","volume":"417","author":"Tsurumaru","year":"2012","journal-title":"Biochem. Biophys. Res. Comm."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"650","DOI":"10.1104\/pp.114.253682","article-title":"A heteromeric membrane-bound prenyltransferase complex from hop catalyzes three sequential aromatic prenylations in the bitter acid pathway","volume":"167","author":"Li","year":"2015","journal-title":"Plant Physiol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1600411","DOI":"10.1002\/pmic.201600411","article-title":"A comprehensive proteome map of glandular trichomes of hop (Humulus lupulus L) female cones: Identification of biosynthetic pathways of the major terpenoid-related compounds and possible transport proteins","volume":"17","author":"Champagne","year":"2017","journal-title":"Proteomics"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1183","DOI":"10.1078\/S0176-1617(04)70145-5","article-title":"Molecular cloning and expression of farnesyl pyrophosphate synthase gene responsible for essential oil biosynthesis in hop (Humulus lupulus)","volume":"158","author":"Okada","year":"2001","journal-title":"J. Plant Physiol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1254","DOI":"10.1104\/pp.108.125187","article-title":"Terpene biosynthesis in glandular trichomes of hop","volume":"148","author":"Wang","year":"2008","journal-title":"Plant Physiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"9914","DOI":"10.1073\/pnas.0904069106","article-title":"Heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis","volume":"106","author":"Wang","year":"2009","journal-title":"Proc. Nat. Acad. Sci. USA"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.1016\/S0168-9452(02)00050-X","article-title":"Cloning and characterisation of chs-specific DNA and cDNA sequences from hop (Humulus lupulus L.)","volume":"162","author":"Patzak","year":"2002","journal-title":"Plant Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"E5223","DOI":"10.1073\/pnas.1802223115","article-title":"Noncatalytic chalcone isomerase-fold proteins in Humulus lupulus are auxiliary components in prenylated flavonoid biosynthesis","volume":"115","author":"Ban","year":"2018","journal-title":"Proc. Nat. Acad. Sci. USA"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1105\/tpc.107.055178","article-title":"EST analysis of hop glandular trichomes identifies an O-methyltransferase that catalyzes the biosynthesis of xanthohumol","volume":"20","author":"Nagel","year":"2008","journal-title":"Plant Cell"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Matou\u0161ek, J., Koc\u00e1bek, T., Patzak, J., F\u00fcssy, Z., Proch\u00e1zkov\u00e1, J., and Heyerick, A. (2012). Combinatorial analysis of lupulin gland transcription factors from R2R3Myb, bHLH and WDR families indicates a complex regulation of chs_H1 genes essential for prenylflavonoid biosynthesis in hop (Humulus lupulus L.). BMC Plant Biol., 12.","DOI":"10.1186\/1471-2229-12-27"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Mishra, A.K., Duraisamy, G.S., Khare, M., Koc\u00e1bek, T., Jakse, J., B\u0159\u00edza, J., Patzak, J., Sano, T., and Matou\u0161ek, J. (2018). Genome-wide transcriptome profiling of transgenic hop (Humulus lupulus L.) constitutively overexpressing HlWRKY1 and HlWDR1 transcription factors. BMC Genom., 19.","DOI":"10.1186\/s12864-018-5125-8"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1007\/s11103-016-0510-7","article-title":"The \u201cputative\u201d role of transcription factors from HlWRKY family in the regulation of the final steps of prenylflavonid and bitter acids biosynthesis in hop (Humulus lupulus L.)","volume":"92","author":"Patzak","year":"2016","journal-title":"Plant Mol. Biol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1016\/j.plantsci.2018.01.004","article-title":"The R2R3 transcription factor HlMYB8 and its role in flavonoid biosynthesis in hop (Humulus lupulus L.)","volume":"269","author":"Mishra","year":"2018","journal-title":"Plant Sci."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Pokorn, T., Radi\u0161ek, S., Javornik, B., \u0160tajner, N., and Jak\u0161e, J. (2017). Development of hop transcriptome to support research into host-viroid interactions. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0184528"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"\u0160tajner, N., Radi\u0161ek, S., Mishra, A.K., Nath, V.S., Matou\u0161ek, J., and Jak\u0161e, J. (2019). Evaluation of disease severity and global transcriptome response induced by citrus bark cracking viroid, hop latent viroid, and their co-Infection in hop (Humulus lupulus L.). Int. J. Mol. Sci., 20.","DOI":"10.3390\/ijms20133154"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Nath, V.S., Shrestha, A., Awasthi, P., Mishra, A.K., Koc\u00e1bek, T., Matou\u0161ek, J., Se\u010dnik, A., Jak\u0161e, J., Radi\u0161ek, S., and Hallan, V. (2020). Mapping the gene expression spectrum of mediator subunits in response to viroid infection in plants. Int. J. Mol. Sci., 21.","DOI":"10.3390\/ijms21072498"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1007\/s00705-010-0867-x","article-title":"Ribosomal protein L5 and transcription factor IIIA from Arabidopsis thaliana bind in vitro specifically Potato spindle tuber viroid RNA","volume":"156","author":"Eiras","year":"2010","journal-title":"Arch. Virol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1094","DOI":"10.1105\/tpc.16.00100","article-title":"A land plant-specific transcription factor directly enhances transcription of a pathogenic noncoding RNA template by DNA-dependent RNA Polymerase II","volume":"28","author":"Wang","year":"2016","journal-title":"Plant Cell"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"e01004-18","DOI":"10.1128\/JVI.01004-18","article-title":"Potato spindle tuber viroid modulates its replication through a direct interaction with a splicing regulator","volume":"92","author":"Jiang","year":"2018","journal-title":"J. Virol."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Mudiyanselage, S.D.D., Qu, J., Tian, N., Jiang, J., and Wang, Y. (2018). Potato spindle tuber viroid RNA-templated transcription: Factors and regulation. Viruses, 10.","DOI":"10.3390\/v10090503"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Matou\u0161ek, J., Steinbachov\u00e1, L., Dr\u00e1bkov\u00e1, L.Z., Koc\u00e1bek, T., Pot\u011b\u0161il, D., Mishra, A.K., and Honys, D. (2020). Elimination of viroids from tobacco pollen involves a decrease in propagation rate and an increase of the degradation processes. Int. J. Mol. Sci., 21.","DOI":"10.3390\/ijms21083029"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1023\/A:1026531819806","article-title":"A low transmissibility of hop latent viroid through a generative phase of Humulus lupulus L.","volume":"43","author":"Patzak","year":"2000","journal-title":"Biol. Plant."},{"key":"ref_42","unstructured":"Matou\u0161ek, J., Koc\u00e1bek, T., Mishra, A.K., Radi\u0161ek, S., and Steger, G. (2021). The decrease of the propagation rate of hop viroids in pollen and a potential multifunctional role of transcription factor TFIIIA. Book of Abstracts, V. International Humulus Symposium, University of Hohenheim."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1864","DOI":"10.1111\/ijfs.12825","article-title":"Number and size of lupulin glands, glandular trichomes of hop (Humulus lupulus L.), play a key role in contents of bitter acids and polyphenols in hop cone","volume":"50","author":"Patzak","year":"2015","journal-title":"Int. J. Food Sci. Technol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"62","DOI":"10.18832\/kp2003004","article-title":"Contents of xanthohumol in Czech hops","volume":"49","author":"Krofta","year":"2003","journal-title":"Kvasn\u00fd Pr\u016fm."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"201","DOI":"10.17660\/ActaHortic.2005.668.25","article-title":"Contents of prenylflavonoids in Czech hops and beers","volume":"668","author":"Krofta","year":"2005","journal-title":"Acta Hortic."},{"key":"ref_46","first-page":"10","article-title":"Variability in the contents of important compounds for pharmaceutical and brewing industries within hop gene pool","volume":"55","author":"Nesvadba","year":"2009","journal-title":"Agriculture"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Patzak, J., Henychov\u00e1, A., and Matou\u0161ek, J. (2021). Developmental regulation of lupulin gland-associated genes in aroma and bitter hops (Humulus lupulus L.). BMC Plant Biol.","DOI":"10.1186\/s12870-021-03292-z"},{"key":"ref_48","first-page":"12","article-title":"Roles of flavonoids in plants","volume":"100","author":"Samanta","year":"2011","journal-title":"Int. J. Pharm. Sci. Technol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1111\/pce.13906","article-title":"Downy mildew resistance is genetically mediated by prophylactic production of phenylpropanoids in hop","volume":"44","author":"Feiner","year":"2021","journal-title":"Plant Cell Environ."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1007\/s13205-014-0220-2","article-title":"Plant terpenes: Defense responses, phylogenetic analysis, regulation and clinical applications","volume":"5","author":"Singh","year":"2015","journal-title":"3 Biotech"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"159","DOI":"10.17221\/27\/2020-CJGPB","article-title":"Assessment of epigenetic methylation changes in hop (Humulus lupulus) plants obtained by meristem culture","volume":"56","author":"Patzak","year":"2020","journal-title":"Czech J. Genet. Plant Breed."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1023\/A:1024096401424","article-title":"Assessment of somaclonal variability in hop (Humulus lupulus L.) in vitro meristem cultures and clones by molecular methods","volume":"131","author":"Patzak","year":"2003","journal-title":"Euphytica"},{"key":"ref_53","unstructured":"Patzak, J., Svoboda, P., Henychov\u00e1, A., and Mal\u00ed\u0159ov\u00e1, I. (2017, January 25\u201329). Detection of hop viruses and viroids by qRT-PCR in the Czech Republic. Proceedings of the Scientific Commission of IHGC, Stefan am Walde, Austria."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"545","DOI":"10.1139\/G10-024","article-title":"Evaluation of genetic variability of wild hops (Humulus lupulus L.) in Canada and the Caucasus region by chemical and molecular methods","volume":"53","author":"Patzak","year":"2010","journal-title":"Genome"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"428","DOI":"10.1093\/pcp\/pcu169","article-title":"The draft genome of hop (Humulus lupulus), an essence for brewing","volume":"56","author":"Natsume","year":"2015","journal-title":"Plant Cell Physiol."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"bax009","DOI":"10.1093\/database\/bax009","article-title":"HopBase: A unified resource for Humulus genomics","volume":"2017","author":"Hill","year":"2017","journal-title":"Database"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"e20072","DOI":"10.1002\/tpg2.20072","article-title":"A draft phased assembly of the diploid Cascade hop (Humulus lupulus) genome","volume":"14","author":"Kingan","year":"2021","journal-title":"Plant Genome"}],"container-title":["Plants"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2223-7747\/10\/11\/2297\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:23:32Z","timestamp":1760167412000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2223-7747\/10\/11\/2297"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,10,26]]},"references-count":57,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2021,11]]}},"alternative-id":["plants10112297"],"URL":"https:\/\/doi.org\/10.3390\/plants10112297","relation":{},"ISSN":["2223-7747"],"issn-type":[{"value":"2223-7747","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,10,26]]}}}