2l9w
From Proteopedia
Solution Structure of the C-terminal domain of Prp24
Structural highlights
FunctionPRP24_YEAST Binds preferentially to the U4/U6 hybrid snRNAs. Can stimulate the annealing of U4 and U6. Could participate in both the formation and disassembly of the U4/U6 hybrid during splicing. Publication Abstract from PubMedThe essential splicing factor Prp24 contains four RNA Recognition Motif (RRM) domains, and functions to anneal U6 and U4 RNAs during spliceosome assembly. Here, we report the structure and characterization of the C-terminal RRM4. This domain adopts a novel non-canonical RRM fold with two additional flanking alpha-helices that occlude its beta-sheet face, forming an occluded RRM (oRRM) domain. The flanking helices form a large electropositive surface. oRRM4 binds to and unwinds the U6 internal stem loop (U6 ISL), a stable helix that must be unwound during U4/U6 assembly. NMR data indicate that the process starts with the terminal base pairs of the helix and proceeds toward the loop. We propose a mechanistic and structural model of Prp24's annealing activity in which oRRM4 functions to destabilize the U6 ISL during U4/U6 assembly. A novel occluded RNA recognition motif in Prp24 unwinds the U6 RNA internal stem loop.,Martin-Tumasz S, Richie AC, Clos LJ 2nd, Brow DA, Butcher SE Nucleic Acids Res. 2011 Jun 7. PMID:21653550[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|