4x86
From Proteopedia
Crystal structure of BAG6-Ubl4a complex
Structural highlights
FunctionUBL4A_HUMAN Component of the BAT3 complex, a multiprotein complex involved in the post-translational delivery of tail-anchored (TA) membrane proteins to the endoplasmic reticulum membrane. TA membrane proteins, also named type II transmembrane proteins, contain a single C-terminal transmembrane region. The complex acts by facilitating TA proteins capture by ASNA1/TRC40: it is recruited to ribosomes synthesizing membrane proteins, interacts with the transmembrane region of newly released TA proteins, and transfers them to ASNA1/TRC40 for targeting.[1] Publication Abstract from PubMedBAG6 is an essential protein that functions in two distinct biological pathways, ubiquitin-mediated protein degradation of defective polypeptides and tail-anchored (TA) transmembrane protein biogenesis in mammals, although its structural and functional properties remain unknown. We solved a crystal structure of the C-terminal heterodimerization domains of BAG6 and Ubl4a, and characterized their interaction biochemically. Unexpectedly, the specificity and structure of the C-terminus of BAG6, which was previously classified as a BAG domain, were completely distinct from those of the canonical BAG domain. Furthermore, the tight association of BAG6 and Ubl4a resulted in modulation of Ubl4a protein stability in cells. Therefore, we propose to designate the Ubl4a-binding region of BAG6 as the novel BAGS (BAG-similar) domain. The structure of Ubl4a, which interacts with BAG6, is similar to the yeast homologue Get5, which forms a homodimer. These observations indicate that the BAGS domain of BAG6 promotes the TA protein biogenesis pathway in mammals by the interaction with Ubl4a. Structure of a BAG6 (Bcl-2-associated athanogene 6)-Ubl4a (Ubiquitin-like protein 4a) Complex Reveals a Novel Binding Interface that Functions in Tail-Anchored Protein Biogenesis.,Kuwabara N, Minami R, Yokota N, Matsumoto H, Senda T, Kawahara H, Kato R J Biol Chem. 2015 Feb 20. pii: jbc.M114.631804. PMID:25713138[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|