Involucrin is a protein component of human skin and in humans is encoded by the IVLgene.[1][2] 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[7]
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.[8]
Structure
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]
↑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.
↑Balasubramanian S, Zhu L, Eckert RL (November 2006). "Apigenin inhibition of involucrin gene expression is associated with a specific reduction in phosphorylation of protein kinase Cdelta Tyr311". The Journal of Biological Chemistry. 281 (47): 36162–72. doi:10.1074/jbc.M605368200. PMID16982614.
↑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.
Eckert RL, Crish JF, Efimova T, Dashti SR, Deucher A, Bone F, Adhikary G, Huang G, Gopalakrishnan R, Balasubramanian S (July 2004). "Regulation of involucrin gene expression". The Journal of Investigative Dermatology. 123 (1): 13–22. doi:10.1111/j.0022-202X.2004.22723.x. PMID15191537.
Rice RH, Green H (November 1979). "Presence in human epidermal cells of a soluble protein precursor of the cross-linked envelope: activation of the cross-linking by calcium ions". Cell. 18 (3): 681–94. doi:10.1016/0092-8674(79)90123-5. PMID42494.
Welter JF, Crish JF, Agarwal C, Eckert RL (May 1995). "Fos-related antigen (Fra-1), junB, and junD activate human involucrin promoter transcription by binding to proximal and distal AP1 sites to mediate phorbol ester effects on promoter activity". The Journal of Biological Chemistry. 270 (21): 12614–22. doi:10.1074/jbc.270.21.12614. PMID7759510.
Volz A, Korge BP, Compton JG, Ziegler A, Steinert PM, Mischke D (October 1993). "Physical mapping of a functional cluster of epidermal differentiation genes on chromosome 1q21". Genomics. 18 (1): 92–9. doi:10.1006/geno.1993.1430. PMID8276421.
Takahashi H, Iizuka H (January 1993). "Analysis of the 5'-upstream promoter region of human involucrin gene: activation by 12-O-tetradecanoylphorbol-13-acetate". The Journal of Investigative Dermatology. 100 (1): 10–5. doi:10.1111/1523-1747.ep12349867. PMID8380829.
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.
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.
Steinert PM, Marekov LN (January 1997). "Direct evidence that involucrin is a major early isopeptide cross-linked component of the keratinocyte cornified cell envelope". The Journal of Biological Chemistry. 272 (3): 2021–30. doi:10.1074/jbc.272.3.2021. PMID8999895.
Robinson NA, Lapic S, Welter JF, Eckert RL (May 1997). "S100A11, S100A10, annexin I, desmosomal proteins, small proline-rich proteins, plasminogen activator inhibitor-2, and involucrin are components of the cornified envelope of cultured human epidermal keratinocytes". The Journal of Biological Chemistry. 272 (18): 12035–46. doi:10.1074/jbc.272.18.12035. PMID9115270.
Ng DC, Su MJ, Kim R, Bikle DD (January 1996). "Regulation of involucrin gene expression by calcium in normal human keratinocytes". Frontiers in Bioscience. 1: a16–24. doi:10.2741/A101. PMID9159190.
Marekov LN, Steinert PM (July 1998). "Ceramides are bound to structural proteins of the human foreskin epidermal cornified cell envelope". The Journal of Biological Chemistry. 273 (28): 17763–70. doi:10.1074/jbc.273.28.17763. PMID9651377.
Crish JF, Zaim TM, Eckert RL (November 1998). "The distal regulatory region of the human involucrin promoter is required for expression in epidermis". The Journal of Biological Chemistry. 273 (46): 30460–5. doi:10.1074/jbc.273.46.30460. PMID9804813.
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.
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.
Crish JF, Bone F, Banks EB, Eckert RL (January 2002). "The human involucrin gene contains spatially distinct regulatory elements that regulate expression during early versus late epidermal differentiation". Oncogene. 21 (5): 738–47. doi:10.1038/sj.onc.1205038. PMID11850802.