title: RNF220, an E3 ubiquitin ligase that targets Sin3B for ubiquitination.
abstract: Modification of proteins by ubiquitination plays important roles in various cellular processes. During this process, the target specificity is determined by ubiquitin ligases. Here we identify RNF220 (RING finger protein 220) as a novel ubiquitin ligase for Sin3B. As a conserved RING protein, RNF220 can bind E2 and mediate auto-ubiquitination of itself. Through a yeast two-hybrid screen, we isolated Sin3B as one of its targets, which is a scaffold protein of the Sin3/HDAC (histone deacetylase) corepressor complex. RNF220 specifically interacts with Sin3B both in vitro and in vivo. Sin3B can be regulated by the ubiquitin-proteasome system. Co-expression of RNF220 promotes the ubiquitination and proteasomal degradation of Sin3B. Taken together, these results reveal a new mechanism for regulating the Sin3/HDAC complex.
authors.affiliation: CAS-Max Planck Junior Scientist Group on Developmental Biology, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, 32 Jiaochang East Road, Kunming 650223, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Kong
authors.forename: Wanli
authors.initials: W
authors.lastname: Zeng
authors.forename: Jingyang
authors.initials: J
authors.lastname: Wu
authors.forename: Wanling
authors.initials: W
authors.lastname: Hu
authors.forename: Chaocui
authors.initials: C
authors.lastname: Li
authors.forename: Bingyu
authors.initials: B
authors.lastname: Mao
mesh_terms: D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D012097:Repressor Proteins / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D012097:Repressor Proteins; C115812:Sin3b protein, mouse; C548734:RNF220 protein, mouse; D044767:Ubiquitin-Protein Ligases