title: Characterization of TRIM62 as a RING finger E3 ubiquitin ligase and its subcellular localization.
abstract: TRIM62, also named DEAR1, is a member of the TRIM/RBCC family, which includes proteins with conserved RING finger, B-box and coiled-coil domains. Several reports have identified a role for this family in cancer, retroviral infection and innate immunity. In this study, the E3 ubiquitin ligase activity and subcellular localization of TRIM62 were characterized. TRIM62, in association with the E2 enzyme UbcH5b, was found to catalyze self-ubiquitination in vitro, a process that required an intact RING finger domain. A ubiquitination assay performed in HEK293T cells further confirmed the E3 ubiquitin ligase activity and self-ubiquitination activity of TRIM62 and the requirement of the RING finger domain. Importantly, the treatment of HEK293T cells with a proteasome inhibitor stabilized poly-ubiquitinated TRIM62, indicating that self-ubiquitination promoted the proteasomal degradation of TRIM62. Additionally, TRIM62 and its two mutants were distinctly localized in the cytoplasm in both HEK293T and HeLa cells. Collectively, our data indicate that TRIM62, a cytoplasmic protein, is a RING finger domain-dependent E3 ubiquitin ligase that catalyzes self-ubiquitination both in vitro and in vivo.
authors: Research Group of HIV Molecular Epidemiology and Virology, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, PR China. lance.huang86@gmail.com
authors: Fang
authors: F
authors: Huang
authors: Han
authors: H
authors: Xiao
authors: Bin-Lian
authors: BL
authors: Sun
authors: Rong-Ge
authors: RG
authors: Yang
mesh_terms: D003593:Cytoplasm / Q000201:enzymology*; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D054829:RING Finger Domains; D000070584:Tripartite Motif Proteins; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D000070584:Tripartite Motif Proteins; C583162:TRIM62 protein, human; D044767:Ubiquitin-Protein Ligases