Ubiquitin thioesterase OTUB1 also known as otubain-1 is an enzyme that in humans is encoded by the OTUB1gene.[5][6] Alternative splicing results in multiple transcript variants.
Function
Otubain-1 is a member of the OTU (ovarian tumor) superfamily of predicted cysteine proteases. The encoded protein is a highly specific ubiquitin iso-peptidase, and cleaves ubiquitin from branched poly-ubiquitin chains, being specific for lysine48 -linked polyubiquitin but not lysine63 -linked polyubiquitin.[7] It interacts with another ubiquitin protease and an E3 ubiquitin ligase that inhibits cytokine gene transcription in the immune system. It is proposed to function in specific ubiquitin-dependent pathways, possibly by providing an editing function for polyubiquitin chain growth.[6]
^ abEdelmann MJ, Iphöfer A, Akutsu M, Altun M, di Gleria K, Kramer HB, Fiebiger E, Dhe-Paganon S, Kessler BM (March 2009). "Structural basis and specificity of human otubain 1-mediated deubiquitination". Biochem. J. 418 (2): 379–90. doi:10.1042/BJ20081318. PMID18954305.
^Soares L, Seroogy C, Skrenta H, Anandasabapathy N, Lovelace P, Chung CD, Engleman E, Fathman CG (January 2004). "Two isoforms of otubain 1 regulate T cell anergy via GRAIL". Nat. Immunol. 5 (1): 45–54. doi:10.1038/ni1017. PMID14661020.