Structural Insights into RNA Recognition by the Alternate-Splicing Regulator CUG-Binding Protein 1.
Teplova, M., Song, J., Gaw, H.Y., Teplov, A., Patel, D.J.(2010) Structure 18: 1364-1377
- PubMed: 20947024 
- DOI: https://doi.org/10.1016/j.str.2010.06.018
- Primary Citation of Related Structures:  
3NMR, 3NNA, 3NNC, 3NNH - PubMed Abstract: 
CUG-binding protein 1 (CUGBP1) regulates multiple aspects of nuclear and cytoplasmic mRNA processing, with implications for onset of myotonic dystrophy. CUGBP1 harbors three RRM domains and preferentially targets UGU-rich mRNA elements. We describe crystal structures of CUGBP1 RRM1 and tandem RRM1/2 domains bound to RNAs containing tandem UGU(U/G) elements. Both RRM1 in RRM1-RNA and RRM2 in RRM1/2-RNA complexes use similar principles to target UGU(U/G) elements, with recognition mediated by face-to-edge stacking and water-mediated hydrogen-bonding networks. The UG step adopts a left-handed Z-RNA conformation, with the syn guanine recognized through Hoogsteen edge-protein backbone hydrogen-bonding interactions. NMR studies on the RRM1/2-RNA complex establish that both RRM domains target tandem UGUU motifs in solution, whereas filter-binding assays identify a preference for recognition of GU over AU or GC steps. We discuss the implications of CUGBP1-mediated targeting and sequestration of UGU(U/G) elements on pre-mRNA alternative-splicing regulation, translational regulation, and mRNA decay.
Organizational Affiliation: 
Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.