A member of the tenascin family, tenascin X (TN-X) also known as hexabrachion-like protein is a glycoprotein that is expressed in connective tissues including skin, joints and muscles. In humans, tenascin X is encoded by the TNXBgene.[1]
This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. The structure of this gene is unusual in that it overlaps the CREBL1 and CYP21A2 genes at its 5' and 3' ends, respectively.[2]
Function
This gene encodes a member of the tenascin family of extracellular matrix glycoproteins. The tenascins have anti-adhesive effects, as opposed to fibronectin which is adhesive. This protein is thought to function in matrix maturation during wound healing.[2]
Clinical significance
Deficiency causes one of the types of Ehlers-Danlos syndrome where collagen density is reduced and elastic fibers are fragmentated.[3]
References
↑Tee MK, Thomson AA, Bristow J, Miller WL (July 1995). "Sequences promoting the transcription of the human XA gene overlapping P450c21A correctly predict the presence of a novel, adrenal-specific, truncated form of tenascin-X". Genomics. 28 (2): 171–8. doi:10.1006/geno.1995.1128. PMID8530023.
↑Zweers, MC; Schalkwijk, J; Van Kuppevelt, TH; Van Vlijmen-Willems, IM; Bergers, M; Lethias, C; Lamme, EN (2005). "Transplantation of reconstructed human skin on nude mice: a model system to study expression of human tenascin-X and elastic fiber components". Cell and Tissue Research. 319 (2): 279–87. doi:10.1007/s00441-004-1011-6. PMID15558324.
Further reading
Goepel C (2008). "Differential elastin and tenascin immunolabeling in the uterosacral ligaments in postmenopausal women with and without pelvic organ prolapse". Acta Histochem. 110 (3): 204–9. doi:10.1016/j.acthis.2007.10.014. PMID18155129.
Egging D, van Vlijmen-Willems I, van Tongeren T, et al. (2007). "Wound healing in tenascin-X deficient mice suggests that tenascin-X is involved in matrix maturation rather than matrix deposition". Connect. Tissue Res. 48 (2): 93–8. doi:10.1080/03008200601166160. PMID17453911.
Kato A, Endo T, Abiko S, et al. (2008). "Induction of truncated form of tenascin-X (XB-S) through dissociation of HDAC1 from SP-1/HDAC1 complex in response to hypoxic conditions". Exp. Cell Res. 314 (14): 2661–73. doi:10.1016/j.yexcr.2008.05.019. PMID18588874.
Bristow J, Carey W, Egging D, Schalkwijk J (2005). "Tenascin-X, collagen, elastin, and the Ehlers-Danlos syndrome". American Journal of Medical Genetics. 139C (1): 24–30. doi:10.1002/ajmg.c.30071. PMID16278880.
Kamatani Y, Matsuda K, Ohishi T, et al. (2008). "Identification of a significant association of a single nucleotide polymorphism in TNXB with systemic lupus erythematosus in a Japanese population". J. Hum. Genet. 53 (1): 64–73. doi:10.1007/s10038-007-0219-1. PMID18058064.
Vignal C, Bansal AT, Balding DJ, et al. (2009). "Genetic association of the major histocompatibility complex with rheumatoid arthritis implicates two non-DRB1 loci". Arthritis Rheum. 60 (1): 53–62. doi:10.1002/art.24138. PMID19116923.
