4dkk
From Proteopedia
The X-ray Crystal Structure of the Human STAU1 SSM-'RBD'5 Domain-Swapped Dimer
Structural highlights
Function[STAU1_HUMAN] Binds double-stranded RNA (regardless of the sequence) and tubulin. May play a role in specific positioning of mRNAs at given sites in the cell by cross-linking cytoskeletal and RNA components, and in stimulating their translation at the site. Publication Abstract from PubMedStaufen1 (STAU1)-mediated mRNA decay (SMD) degrades mammalian-cell mRNAs that bind the double-stranded RNA (dsRNA)-binding protein STAU1 in their 3' untranslated region. We report a new motif, which typifies STAU homologs from all vertebrate classes, that is responsible for human STAU1 (hSTAU1) homodimerization. Our crystal structure and mutagenesis analyses reveal that this motif, which we named the Staufen-swapping motif (SSM), and the dsRNA-binding domain 5 ('RBD'5) mediate protein dimerization: the two SSM alpha-helices of one molecule interact primarily through a hydrophobic patch with the two 'RBD'5 alpha-helices of a second molecule. 'RBD'5 adopts the canonical alpha-beta-beta-beta-alpha fold of a functional RBD, but it lacks residues and features required to bind duplex RNA. In cells, SSM-mediated hSTAU1 dimerization increases the efficiency of SMD by augmenting hSTAU1 binding to the ATP-dependent RNA helicase hUPF1. Dimerization regulates keratinocyte-mediated wound healing and many other cellular processes. Staufen1 dimerizes through a conserved motif and a degenerate dsRNA-binding domain to promote mRNA decay.,Gleghorn ML, Gong C, Kielkopf CL, Maquat LE Nat Struct Mol Biol. 2013 Apr;20(4):515-24. doi: 10.1038/nsmb.2528. Epub 2013 Mar, 24. PMID:23524536[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
