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2f9j
From Proteopedia
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3.0 angstrom resolution structure of a Y22M mutant of the spliceosomal protein p14 bound to a region of SF3b155
Overview
The precise excision of introns from precursor mRNAs (pre-mRNAs) in eukaryotes is accomplished by the spliceosome, a complex assembly containing five small nuclear ribonucleoprotein (snRNP) particles. Human p14, a component of the spliceosomal U2 and U11/U12 snRNPs, has been shown to associate directly with the pre-mRNA branch adenosine early in spliceosome assembly and within the fully assembled spliceosome. Here we report the 2.5-A crystal structure of a complex containing p14 and a peptide derived from the p14-associated U2 snRNP component SF3b155. p14 contains an RNA recognition motif (RRM), the surface of which is largely occluded by a C-terminal alpha-helix and a portion of the SF3b155 peptide. An analysis of RNA.protein crosslinking to wild-type and mutant p14 shows that the branch adenosine directly interacts with a conserved aromatic within a pocket on the surface of the complex. This result, combined with a comparison of the structure with known RRMs and pseudoRRMs as well as model-building by using the electron cryomicroscopy structure of a spliceosomal U11/U12 di-snRNP, suggests that p14.SF3b155 presents a noncanonical surface for RNA recognition at the heart of the mammalian spliceosome.
About this Structure
2F9J is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of a core spliceosomal protein interface., Schellenberg MJ, Edwards RA, Ritchie DB, Kent OA, Golas MM, Stark H, Luhrmann R, Glover JN, MacMillan AM, Proc Natl Acad Sci U S A. 2006 Jan 31;103(5):1266-71. Epub 2006 Jan 23. PMID:16432215
Page seeded by OCA on Thu Feb 21 17:19:06 2008
