Involucrin is a protein component of human skin and in humans is encoded by the IVLgene.[5][6] In binding the protein loricrin, involucrin contributes to the formation of a cell envelope that protects corneocytes in the skin.
Involucrin is synthesised in the stratum spinosum and cross linked in the stratum granulosum by the transglutaminase enzyme that makes it highly stable. Thus it provides structural support to the cell, thereby allowing the cell to resist invasion by micro-organisms.[citation needed]
As one of the precursor proteins of the cornified cell envelope, involucrin is markedly increased in inflammatory skin diseases such as psoriasis[11]
Lamellar ichthyosis involves a decrease in expression of involucrin. This decrease could contribute to the altered desquamation process seen in the disease, since the clinical improvement associated with retinoid treatment is accompanied by increased expression of involucrin.[12]
Involucrin consists of a conservedN-terminal region of about 75 amino acid residues followed by two extremely variable length segments that contain glutamine-rich tandem repeats. The glutamine residues in the tandem repeats are the substrate for the transglutaminase in the cross-linking reaction. The total size of the protein varies from 285 residues (in dog) to 835 residues (in orangutan).[citation needed]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Eckert RL, Green H (August 1986). "Structure and evolution of the human involucrin gene". Cell. 46 (4): 583–9. doi:10.1016/0092-8674(86)90884-6. PMID2873896. S2CID39293076.583-9&rft.date=1986-08&rft_id=https://api.semanticscholar.org/CorpusID:39293076#id-name=S2CID&rft_id=info:pmid/2873896&rft_id=info:doi/10.1016/0092-8674(86)90884-6&rft.aulast=Eckert&rft.aufirst=RL&rft.au=Green, H&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
^Djian P, Phillips M, Easley K, Huang E, Simon M, Rice RH, Green H (November 1993). "The involucrin genes of the mouse and the rat: study of their shared repeats". Molecular Biology and Evolution. 10 (6): 1136–49. doi:10.1093/oxfordjournals.molbev.a040069. PMID8277848.1136-49&rft.date=1993-11&rft_id=info:doi/10.1093/oxfordjournals.molbev.a040069&rft_id=info:pmid/8277848&rft.aulast=Djian&rft.aufirst=P&rft.au=Phillips, M&rft.au=Easley, K&rft.au=Huang, E&rft.au=Simon, M&rft.au=Rice, RH&rft.au=Green, H&rft_id=https://doi.org/10.1093%2Foxfordjournals.molbev.a040069&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
^Eckert RL, Yaffe MB, Crish JF, Murthy S, Rorke EA, Welter JF (May 1993). "Involucrin--structure and role in envelope assembly". The Journal of Investigative Dermatology. 100 (5): 613–7. doi:10.1111/1523-1747.ep12472288. PMID8098344.613-7&rft.date=1993-05&rft_id=info:doi/10.1111/1523-1747.ep12472288&rft_id=info:pmid/8098344&rft.aulast=Eckert&rft.aufirst=RL&rft.au=Yaffe, MB&rft.au=Crish, JF&rft.au=Murthy, S&rft.au=Rorke, EA&rft.au=Welter, JF&rft_id=https://doi.org/10.1111%2F1523-1747.ep12472288&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
^Takahashi H, Hashimoto Y, Ishida-Yamamoto A, Iizuka H (September 2005). "Roxithromycin suppresses involucrin expression by modulation of activator protein-1 and nuclear factor-kappaB activities of keratinocytes". Journal of Dermatological Science. 39 (3): 175–82. doi:10.1016/j.jdermsci.2005.03.006. PMID16140218.175-82&rft.date=2005-09&rft_id=info:doi/10.1016/j.jdermsci.2005.03.006&rft_id=info:pmid/16140218&rft.aulast=Takahashi&rft.aufirst=H&rft.au=Hashimoto, Y&rft.au=Ishida-Yamamoto, A&rft.au=Iizuka, H&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
^Peña-Penabad C, de Unamuno P, García Silva J, Ludeña MD, González Sarmiento R, Pérez-Arellano JL (1999). "Altered expression of immunoreactive involucrin in lamellar ichthyosis". European Journal of Dermatology. 9 (3): 197–201. PMID10210784.197-201&rft.date=1999&rft_id=info:pmid/10210784&rft.aulast=Peña-Penabad&rft.aufirst=C&rft.au=de Unamuno, P&rft.au=García Silva, J&rft.au=Ludeña, MD&rft.au=González Sarmiento, R&rft.au=Pérez-Arellano, JL&rft_id=http://www.john-libbey-eurotext.fr/medline.md?issn=1167-1122&vol=9&iss=3&page=197&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
Heller M, Flemington E, Kieff E, Deininger P (March 1985). "Repeat arrays in cellular DNA related to the Epstein-Barr virus IR3 repeat". Molecular and Cellular Biology. 5 (3): 457–65. doi:10.1128/mcb.5.3.457. PMC366737. PMID2985954.457-65&rft.date=1985-03&rft_id=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC366737#id-name=PMC&rft_id=info:pmid/2985954&rft_id=info:doi/10.1128/mcb.5.3.457&rft.aulast=Heller&rft.aufirst=M&rft.au=Flemington, E&rft.au=Kieff, E&rft.au=Deininger, P&rft_id=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC366737&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
Lopez-Bayghen E, Vega A, Cadena A, Granados SE, Jave LF, Gariglio P, Alvarez-Salas LM (January 1996). "Transcriptional analysis of the 5'-noncoding region of the human involucrin gene". The Journal of Biological Chemistry. 271 (1): 512–20. doi:10.1074/jbc.271.1.512. PMID8550612.512-20&rft.date=1996-01&rft_id=info:doi/10.1074/jbc.271.1.512&rft_id=info:pmid/8550612&rft.aulast=Lopez-Bayghen&rft.aufirst=E&rft.au=Vega, A&rft.au=Cadena, A&rft.au=Granados, SE&rft.au=Jave, LF&rft.au=Gariglio, P&rft.au=Alvarez-Salas, LM&rft_id=https://doi.org/10.1074%2Fjbc.271.1.512&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
Takahashi H, Kobayashi H, Matsuo S, Iizuka H (1995). "Repression of involucrin gene expression by transcriptional enhancer factor 1 (TEF-1)". Archives of Dermatological Research. 287 (8): 740–6. doi:10.1007/BF01105799. PMID8554386. S2CID23203303.740-6&rft.date=1995&rft_id=https://api.semanticscholar.org/CorpusID:23203303#id-name=S2CID&rft_id=info:pmid/8554386&rft_id=info:doi/10.1007/BF01105799&rft.aulast=Takahashi&rft.aufirst=H&rft.au=Kobayashi, H&rft.au=Matsuo, S&rft.au=Iizuka, H&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
Lee CH, Marekov LN, Kim S, Brahim JS, Park MH, Steinert PM (July 2000). "Small proline-rich protein 1 is the major component of the cell envelope of normal human oral keratinocytes". FEBS Letters. 477 (3): 268–72. doi:10.1016/S0014-5793(00)01806-8. PMID10908733. S2CID12228606.268-72&rft.date=2000-07&rft_id=https://api.semanticscholar.org/CorpusID:12228606#id-name=S2CID&rft_id=info:pmid/10908733&rft_id=info:doi/10.1016/S0014-5793(00)01806-8&rft.aulast=Lee&rft.aufirst=CH&rft.au=Marekov, LN&rft.au=Kim, S&rft.au=Brahim, JS&rft.au=Park, MH&rft.au=Steinert, PM&rft_id=https://doi.org/10.1016%2FS0014-5793%2800%2901806-8&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">
Candi E, Oddi S, Terrinoni A, Paradisi A, Ranalli M, Finazzi-Agró A, Melino G (September 2001). "Transglutaminase 5 cross-links loricrin, involucrin, and small proline-rich proteins in vitro". The Journal of Biological Chemistry. 276 (37): 35014–23. doi:10.1074/jbc.M010157200. PMID11443109.35014-23&rft.date=2001-09&rft_id=info:doi/10.1074/jbc.M010157200&rft_id=info:pmid/11443109&rft.aulast=Candi&rft.aufirst=E&rft.au=Oddi, S&rft.au=Terrinoni, A&rft.au=Paradisi, A&rft.au=Ranalli, M&rft.au=Finazzi-Agró, A&rft.au=Melino, G&rft_id=https://doi.org/10.1074%2Fjbc.M010157200&rfr_id=info:sid/en.wikipedia.org:Involucrin" class="Z3988">