This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2i7x
From Proteopedia
|
Structure of Yeast CPSF-100 (Ydh1p)
Overview
Most eukaryotic messenger RNA precursors (pre-mRNAs) undergo extensive, maturational processing, including cleavage and polyadenylation at the, 3'-end. Despite the characterization of many proteins that are required, for the cleavage reaction, the identity of the endonuclease is not known., Recent analyses indicated that the 73-kDa subunit of cleavage and, polyadenylation specificity factor (CPSF-73) might be the endonuclease for, this and related reactions, although no direct data confirmed this. Here, we report the crystal structures of human CPSF-73 at 2.1 A resolution, complexed with zinc ions and a sulphate that might mimic the phosphate, group of the substrate, and the related yeast protein CPSF-100 (Ydh1) at, 2.5 A resolution. Both CPSF-73 and CPSF-100 contain two domains, a, metallo-beta-lactamase domain and a novel beta-CASP (named for, metallo-beta-lactamase, CPSF, Artemis, Snm1, Pso2) domain. The active site, of CPSF-73, with two zinc ions, is located at the interface of the two, domains. Purified recombinant CPSF-73 possesses RNA endonuclease activity, and mutations that disrupt zinc binding in the active site abolish this, activity. Our studies provide the first direct experimental evidence that, CPSF-73 is the pre-mRNA 3'-end-processing endonuclease.
About this Structure
2I7X is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Polyadenylation factor CPSF-73 is the pre-mRNA 3'-end-processing endonuclease., Mandel CR, Kaneko S, Zhang H, Gebauer D, Vethantham V, Manley JL, Tong L, Nature. 2006 Dec 14;444(7121):953-6. Epub 2006 Nov 26. PMID:17128255
Page seeded by OCA on Wed Nov 21 12:11:04 2007
