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1sz9
From Proteopedia
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The RNA polymerase II CTD in mRNA processing: beta-turn recognition and beta-spiral model
Overview
During transcription, RNA polymerase (Pol) II synthesizes eukaryotic, messenger RNA. Transcription is coupled to RNA processing by the, carboxy-terminal domain (CTD) of Pol II, which consists of up to 52, repeats of the sequence Tyr 1-Ser 2-Pro 3-Thr 4-Ser 5-Pro 6-Ser 7 (refs 1, 2). After phosphorylation, the CTD binds tightly to a conserved, CTD-interacting domain (CID) present in the proteins Pcf11 and Nrd1, which, are essential and evolutionarily conserved factors for, polyadenylation-dependent and -independent 3'-RNA processing, respectively. Here we describe the structure of a Ser 2-phosphorylated CTD, peptide bound to the CID domain of Pcf11. The CTD motif Ser 2-Pro 3-Thr, 4-Ser 5 forms a beta-turn that binds to a conserved groove in the CID, domain. The Ser 2 phosphate group does not make direct contact with the, CID domain, but may be recognized indirectly because it stabilizes the, beta-turn with an additional hydrogen bond. Iteration of the peptide, structure results in a compact beta-spiral model of the CTD. The model, suggests that, during the mRNA transcription-processing cycle, compact, spiral regions in the CTD are unravelled and regenerated in a, phosphorylation-dependent manner.
About this Structure
1SZ9 is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Recognition of RNA polymerase II carboxy-terminal domain by 3'-RNA-processing factors., Meinhart A, Cramer P, Nature. 2004 Jul 8;430(6996):223-6. PMID:15241417
Page seeded by OCA on Wed Nov 21 02:51:56 2007
