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2nl8
From Proteopedia
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The origin binding domain of the SV40 large T antigen bound non specifically to a 17 bp palindrome DNA (sites 1 and 3)
Overview
The large T antigen (T-ag) protein binds to and activates DNA replication, from the origin of DNA replication (ori) in simian virus 40 (SV40). Here, we determined the crystal structures of the T-ag origin-binding domain, (OBD) in apo form, and bound to either a 17 bp palindrome (sites 1 and 3), or a 23 bp ori DNA palindrome comprising all four GAGGC binding sites for, OBD. The T-ag OBDs were shown to interact with the DNA through a loop, comprising Ser147-Thr155 (A1 loop), a combination of a DNA-binding helix, and loop (His203-Asn210), and Asn227. The A1 loop traveled back-and-forth, along the major groove and accounted for most of the sequence-determining, contacts with the DNA. Unexpectedly, in both T-ag-DNA structures, the T-ag, OBDs bound DNA independently and did not make direct protein-protein, contacts. The T-ag OBD was also captured bound to a non-consensus site, ATGGC even in the presence of its canonical site GAGGC. Our observations, taken together with the known biochemical and structural features of the, T-ag-origin interaction suggest a model for origin unwinding.
About this Structure
2NL8 is a Single protein structure of sequence from Simian virus 40. Full crystallographic information is available from OCA.
Reference
Structure of the origin-binding domain of simian virus 40 large T antigen bound to DNA., Bochkareva E, Martynowski D, Seitova A, Bochkarev A, EMBO J. 2006 Dec 13;25(24):5961-9. Epub 2006 Nov 30. PMID:17139255
Page seeded by OCA on Tue Jan 29 20:55:42 2008
