This gene is a member of the peptidase C19 family and encodes a protein that is similar to ubiquitin-specific proteases. Though this gene is located on the X chromosome, it escapes X-inactivation.
Depletion of USP9X from two-cell mouse embryos halts blastocyst development and results in slower blastomere cleavage rate, impaired cell adhesion and a loss of cell polarity. It has also been implicated that USP9X is likely to influence developmental processes through signaling pathways of Notch, Wnt, EGF, and mTOR. USP9X has been recognized in studies of mouse and human stem cells involving embryonic, neural and hematopoietic stem cells.[3] High expression is retained in undifferentiated progenitor and stem cells and decreases as differentiation continues. USP9X is a protein-coding gene that has been implicated either directly through mutations or indirectly in a number of neurodevelopmental and neurodegenerative disorders. Three mutations have been connected with X-linked intellectual disability and disrupt neuronal growth and cell migration. Neurodegenerative disorders, such as Alzheimer's, Parkinson's and Huntington's disease, have also been linked to USP9X. Specifically, USP9X has been implicated in the regulation of the phosphorylation and expression of the microtule-associated protein tau, which forms pathological aggregates in Alzheimer's and other tauopathies.[4] Scientists have generated a knockout model where they isolated hippocampal neurons from an USP9X-knockout male mouse, which showed a 43% reduction in axonal length and aborization compared to wildtype.[5]
↑Jones MH, Furlong RA, Burkin H, Chalmers IJ, Brown GM, Khwaja O, Affara NA (1996). "The Drosophila developmental gene fat facets has a human homologue in Xp11.4 which escapes X-inactivation and has related sequences on Yq11.2". Hum. Mol. Genet. 5 (11): 1695–701. doi:10.1093/hmg/5.11.1695. PMID8922996.
↑ 6.06.1Taya S, Yamamoto T, Kanai-Azuma M, Wood SA, Kaibuchi K (Dec 1999). "The deubiquitinating enzyme Fam interacts with and stabilizes beta-catenin". Genes Cells. 4 (12): 757–67. doi:10.1046/j.1365-2443.1999.00297.x. PMID10620020.
↑ 7.07.1Al-Hakim AK, Zagorska A, Chapman L, Deak M, Peggie M, Alessi DR (Apr 2008). "Control of AMPK-related kinases by USP9X and atypical Lys(29)/Lys(33)-linked polyubiquitin chains". Biochem. J. 411 (2): 249–60. doi:10.1042/BJ20080067. PMID18254724.
D'Andrea A, Pellman D (1998). "Deubiquitinating enzymes: a new class of biological regulators". Crit. Rev. Biochem. Mol. Biol. 33 (5): 337–52. doi:10.1080/10409239891204251. PMID9827704.
Andersson B, Wentland MA, Ricafrente JY, Liu W, Gibbs RA (1996). "A "double adaptor" method for improved shotgun library construction". Anal. Biochem. 236 (1): 107–13. doi:10.1006/abio.1996.0138. PMID8619474.
Noma T, Kanai Y, Kanai-Azuma M, Ishii M, Fujisawa M, Kurohmaru M, Kawakami H, Wood SA, Hayashi Y (2002). "Stage- and sex-dependent expressions of Usp9x, an X-linked mouse ortholog of Drosophila Fat facets, during gonadal development and oogenesis in mice". Gene Expr. Patterns. 2 (1–2): 87–91. doi:10.1016/S0925-4773(02)00290-3. PMID12617843.
Bouwmeester T, Bauch A, Ruffner H, Angrand PO, Bergamini G, Croughton K, Cruciat C, Eberhard D, Gagneur J, Ghidelli S, Hopf C, Huhse B, Mangano R, Michon AM, Schirle M, Schlegl J, Schwab M, Stein MA, Bauer A, Casari G, Drewes G, Gavin AC, Jackson DB, Joberty G, Neubauer G, Rick J, Kuster B, Superti-Furga G (2004). "A physical and functional map of the human TNF-alpha/NF-kappa B signal transduction pathway". Nat. Cell Biol. 6 (2): 97–105. doi:10.1038/ncb1086. PMID14743216.
Fu GK, Wang JT, Yang J, Au-Young J, Stuve LL (2004). "Circular rapid amplification of cDNA ends for high-throughput extension cloning of partial genes". Genomics. 84 (1): 205–10. doi:10.1016/j.ygeno.2004.01.011. PMID15203218.
Rush J, Moritz A, Lee KA, Guo A, Goss VL, Spek EJ, Zhang H, Zha XM, Polakiewicz RD, Comb MJ (2005). "Immunoaffinity profiling of tyrosine phosphorylation in cancer cells". Nat. Biotechnol. 23 (1): 94–101. doi:10.1038/nbt1046. PMID15592455.
Al-Hakim AK, Göransson O, Deak M, Toth R, Campbell DG, Morrice NA, Prescott AR, Alessi DR (2005). "14-3-3 cooperates with LKB1 to regulate the activity and localization of QSK and SIK". J. Cell Sci. 118 (Pt 23): 5661–73. doi:10.1242/jcs.02670. PMID16306228.
Beausoleil SA, Villén J, Gerber SA, Rush J, Gygi SP (2006). "A probability-based approach for high-throughput protein phosphorylation analysis and site localization". Nat. Biotechnol. 24 (10): 1285–92. doi:10.1038/nbt1240. PMID16964243.
Mouchantaf R, Azakir BA, McPherson PS, Millard SM, Wood SA, Angers A (2006). "The ubiquitin ligase itch is auto-ubiquitylated in vivo and in vitro but is protected from degradation by interacting with the deubiquitylating enzyme FAM/USP9X". J. Biol. Chem. 281 (50): 38738–47. doi:10.1074/jbc.M605959200. PMID17038327.
Olsen JV, Blagoev B, Gnad F, Macek B, Kumar C, Mortensen P, Mann M (2006). "Global, in vivo, and site-specific phosphorylation dynamics in signaling networks". Cell. 127 (3): 635–48. doi:10.1016/j.cell.2006.09.026. PMID17081983.