title: 'Black sheep' that don't leave the double-stranded RNA-binding domain fold.
abstract: The canonical double-stranded RNA (dsRNA)-binding domain (dsRBD) is composed of an α1-β1-β2-β3-α2 secondary structure that folds in three dimensions to recognize dsRNA. Recently, structural and functional studies of divergent dsRBDs revealed adaptations that include intra- and/or intermolecular protein interactions, sometimes in the absence of detectable dsRNA-binding ability. We describe here how discrete dsRBD components can accommodate pronounced amino-acid sequence changes while maintaining the core fold. We exemplify the growing importance of divergent dsRBDs in mRNA decay by discussing Dicer, Staufen (STAU)1 and 2, trans-activation responsive RNA-binding protein (TARBP)2, protein activator of protein kinase RNA-activated (PKR) (PACT), DiGeorge syndrome critical region (DGCR)8, DEAH box helicase proteins (DHX) 9 and 30, and dsRBD-like fold-containing proteins that have ribosome-related functions. We also elaborate on the computational limitations to discovering yet-to-be-identified divergent dsRBDs.
authors: Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA; Center for RNA Biology, University of Rochester, Rochester, NY 14642, USA.
authors: Michael L
authors: ML
authors: Gleghorn
authors: Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA; Center for RNA Biology, University of Rochester, Rochester, NY 14642, USA. Electronic address: lynne_maquat@urmc.rochester.edu.
authors: Lynne E
authors: LE
authors: Maquat
mesh_terms: D000818:Animals; D006801:Humans; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D012330:RNA, Double-Stranded / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*
chemical_list: D012330:RNA, Double-Stranded; D016601:RNA-Binding Proteins
keywords: RNA metabolism; degenerate dsRBDs; divergent dsRBDs; double-stranded RNA-binding domain; dsRBD–protein interactions; mRNA decay