1w9h
From Proteopedia
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==Overview== | ==Overview== | ||
| - | RNA silencing regulates gene expression through mRNA degradation, translation repression and chromatin remodelling. The fundamental engines | + | RNA silencing regulates gene expression through mRNA degradation, translation repression and chromatin remodelling. The fundamental engines of RNA silencing are RISC and RITS complexes, whose common components are 21-25 nt RNA and an Argonaute protein containing a PIWI domain of unknown function. The crystal structure of an archaeal Piwi protein (AfPiwi) is organised into two domains, one resembling the sugar-binding portion of the lac repressor and another with similarity to RNase H. Invariant residues and a coordinated metal ion lie in a pocket that surrounds the conserved C-terminus of the protein, defining a key functional region in the PIWI domain. Furthermore, two Asp residues, conserved in the majority of Argonaute sequences, align spatially with the catalytic Asp residues of RNase H-like catalytic sites, suggesting that in eukaryotic Argonaute proteins the RNase H-like domain may possess nuclease activity. The conserved region around the C-terminus of the PIWI domain, which is required for small interfering RNA (siRNA) binding to AfPiwi, may function as the receptor site for the obligatory 5' phosphate of siRNAs, thereby specifying the cleavage position of the target mRNA. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Barford, D.]] | [[Category: Barford, D.]] | ||
| - | [[Category: Parker, J | + | [[Category: Parker, J S.]] |
| - | [[Category: Roe, S | + | [[Category: Roe, S M.]] |
[[Category: CD]] | [[Category: CD]] | ||
[[Category: CL]] | [[Category: CL]] | ||
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[[Category: rnai]] | [[Category: rnai]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:41:53 2008'' |
Revision as of 13:41, 21 February 2008
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THE STRUCTURE OF A PIWI PROTEIN FROM ARCHAEOGLOBUS FULGIDUS.
Overview
RNA silencing regulates gene expression through mRNA degradation, translation repression and chromatin remodelling. The fundamental engines of RNA silencing are RISC and RITS complexes, whose common components are 21-25 nt RNA and an Argonaute protein containing a PIWI domain of unknown function. The crystal structure of an archaeal Piwi protein (AfPiwi) is organised into two domains, one resembling the sugar-binding portion of the lac repressor and another with similarity to RNase H. Invariant residues and a coordinated metal ion lie in a pocket that surrounds the conserved C-terminus of the protein, defining a key functional region in the PIWI domain. Furthermore, two Asp residues, conserved in the majority of Argonaute sequences, align spatially with the catalytic Asp residues of RNase H-like catalytic sites, suggesting that in eukaryotic Argonaute proteins the RNase H-like domain may possess nuclease activity. The conserved region around the C-terminus of the PIWI domain, which is required for small interfering RNA (siRNA) binding to AfPiwi, may function as the receptor site for the obligatory 5' phosphate of siRNAs, thereby specifying the cleavage position of the target mRNA.
About this Structure
1W9H is a Single protein structure of sequence from Archaeoglobus fulgidus with , and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Crystal structure of a PIWI protein suggests mechanisms for siRNA recognition and slicer activity., Parker JS, Roe SM, Barford D, EMBO J. 2004 Dec 8;23(24):4727-37. Epub 2004 Nov 25. PMID:15565169
Page seeded by OCA on Thu Feb 21 15:41:53 2008
Categories: Archaeoglobus fulgidus | Single protein | Barford, D. | Parker, J S. | Roe, S M. | CD | CL | NI | Argonaute | Nuclear protein | Piwi domain | Risc | Rnai
