2nub
From Proteopedia
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Structure of Aquifex aeolicus Argonuate
Overview
Gene silencing mediated by RNA interference requires the sequence-specific, recognition of target mRNA by the endonuclease Argonaute, the primary, enzymatic component of the RNA-induced silencing complex. We report the, crystal structure of Aquifex aeolicus Argonaute, refined at 3.2 A, resolution. Relative to recent Argonaute structures, a 24 degree, reorientation of the PAZ domain in our structure opens a basic cleft, between the N-terminal and PAZ domains, exposing the guide strand binding, pocket of PAZ. This rearrangement leads to a branched, Y-shaped system of, grooves that extends through the molecule and merges in a central channel, containing the catalytic residues. A 5.5 ns molecular dynamics simulation, of Argonaute shows a strong tendency of the PAZ and N-terminal domains to, be mobile. Binding of ssDNA to Argonaute monitored by total internal, reflection fluorescence spectroscopy shows biphasic kinetics, also, indicative of domain rearrangement upon DNA binding. Conformational, rearrangement of the PAZ domain may therefore be critical for the, catalytic cycle of Argonaute and the RNA-induced silencing complex.
About this Structure
2NUB is a Single protein structure of sequence from Aquifex aeolicus. Full crystallographic information is available from OCA.
Reference
Structure of Aquifex aeolicus argonaute highlights conformational flexibility of the PAZ domain as a potential regulator of RISC function., Rashid UJ, Paterok D, Koglin A, Gohlke H, Piehler J, Chen JC, J Biol Chem. 2006 Nov 27;. PMID:17130125
Page seeded by OCA on Tue Jan 29 20:59:37 2008
Categories: Aquifex aeolicus | Single protein | Chen, J.C.H. | Gohlke, H. | Koglin, A. | Paterok, D. | Piehler, J. | Rashid, U.J. | Argonaute | Ribonuclease | Risc | Rnai | Rnaseh