2F8S

Crystal structure of Aa-Ago with externally-bound siRNA

Summary for 2F8S

• Entry DOI: 10.2210/pdb2f8s/pdb
• Related: 2F8T
• Descriptor: 5'-R(P*AP*GP*AP*CP*AP*GP*CP*AP*UP*AP*UP*AP*UP*GP*CP*UP*GP*UP*CP*UP*UP*U)-3', Argonaute protein (3 entities in total)
• Functional Keywords: argonaute, sirna, risc loading complex, rna binding protein-rna complex, rna binding protein/rna
• Biological source: Aquifex aeolicus
• Total number of polymer chains: 4
• Total formula weight: 180491.04

Authors

Yuan, Y.R.,Chen, H.Y.,Patel, D.J. (deposition date: 2005-12-03, release date: 2006-10-31, Last modification date: 2023-08-30)

Primary citation

Yuan, Y.R.,Pei, Y.,Chen, H.Y.,Tuschl, T.,Patel, D.J.
A Potential Protein-RNA Recognition Event along the RISC-Loading Pathway from the Structure of A. aeolicus Argonaute with Externally Bound siRNA.
Structure, 14:1557-1565, 2006

PubMed Abstract: Argonaute proteins are key components of the RNA-induced silencing complex (RISC). They provide both architectural and catalytic functionalities associated with small interfering RNA (siRNA) guide strand recognition and subsequent guide strand-mediated cleavage of complementary mRNAs. We report on the 3.0 A crystal structures of 22-mer and 26-mer siRNAs bound to Aquifex aeolicus Argonaute (Aa-Ago), where one 2 nt 3' overhang of the siRNA inserts into a cavity positioned on the outer surface of the PAZ-containing lobe of the bilobal Aa-Ago architecture. The first overhang nucleotide stacks over a tyrosine ring, while the second overhang nucleotide, together with the intervening sugar-phosphate backbone, inserts into a preformed surface cavity. Photochemical crosslinking studies on Aa-Ago with 5-iodoU-labeled single-stranded siRNA and siRNA duplex provide support for this externally bound siRNA-Aa-Ago complex. The structure and biochemical data together provide insights into a protein-RNA recognition event potentially associated with the RISC-loading pathway.

PubMed: 17027504
DOI: 10.1016/j.str.2006.08.009

Experimental method

X-RAY DIFFRACTION (3 Å)