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1mp1
From Proteopedia
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| Gene: | SRm160 (Homo sapiens) | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Solution structure of the PWI motif from SRm160
Overview
The PWI motif is a highly conserved domain of unknown function in the SRm160 splicing and 3'-end cleavage-stimulatory factor, as well as in several other known or putative pre-mRNA processing components. We show here that the PWI motif is a new type of RNA/DNA-binding domain that has an equal preference for single- and double-stranded nucleic acids. Deletion of the motif prevents SRm160 from binding RNA and stimulating 3'-end cleavage, and its substitution with a heterologous RNA-binding domain restores these functions. The NMR solution structure of the SRm160-PWI motif reveals a novel, four-helix bundle and represents the first example of an alpha-helical fold that can bind single-stranded (ss)RNA. Structure-guided mutagenesis indicates that the same surface is involved in RNA and DNA binding and requires the cooperative action of a highly conserved, adjacent basic region. Thus, the PWI motif is a novel type of nucleic acid-binding domain that likely has multiple important functions in pre-mRNA processing, including SRm160-dependent stimulation of 3'-end formation.
About this Structure
1MP1 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure and function of the PWI motif: a novel nucleic acid-binding domain that facilitates pre-mRNA processing., Szymczyna BR, Bowman J, McCracken S, Pineda-Lucena A, Lu Y, Cox B, Lambermon M, Graveley BR, Arrowsmith CH, Blencowe BJ, Genes Dev. 2003 Feb 15;17(4):461-75. PMID:12600940
Page seeded by OCA on Sun Mar 30 22:19:05 2008
