1si2
From Proteopedia
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Crystal structure of the PAZ domain of human eIF2c1 in complex with a 9-mer siRNA-like duplex of deoxynucleotide overhang
Overview
Short RNAs mediate gene silencing, a process associated with virus, resistance, developmental control and heterochromatin formation in, eukaryotes. RNA silencing is initiated through Dicer-mediated processing, of double-stranded RNA into small interfering RNA (siRNA). The siRNA guide, strand associates with the Argonaute protein in silencing effector, complexes, recognizes complementary sequences and targets them for, silencing. The PAZ domain is an RNA-binding module found in Argonaute and, some Dicer proteins and its structure has been determined in the free, state. Here, we report the 2.6 A crystal structure of the PAZ domain from, human Argonaute eIF2c1 bound to both ends of a 9-mer siRNA-like duplex. In, a sequence-independent manner, PAZ anchors the 2-nucleotide 3' overhang of, the siRNA-like duplex within a highly conserved binding pocket, and, secures the duplex by binding the 7-nucleotide phosphodiester backbone of, the overhang-containing strand and capping the 5'-terminal residue of the, complementary strand. On the basis of the structure and on binding assays, we propose that PAZ might serve as an siRNA-end-binding module for siRNA, transfer in the RNA silencing pathway, and as an anchoring site for the 3', end of guide RNA within silencing effector complexes.
About this Structure
1SI2 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structural basis for overhang-specific small interfering RNA recognition by the PAZ domain., Ma JB, Ye K, Patel DJ, Nature. 2004 May 20;429(6989):318-22. PMID:15152257
Page seeded by OCA on Mon Nov 12 19:14:05 2007
