Mechanism of DNA translocation in a replicative hexameric helicase

Enemark, E. J., Joshua-Tor, L. (July 2006) Mechanism of DNA translocation in a replicative hexameric helicase. Nature, 442 (7100). pp. 270-275. ISSN 1476-4687 (Electronic) (Public Dataset)

Abstract

The E1 protein of papillomavirus is a hexameric ring helicase belonging to the AAA + family. The mechanism that couples the ATP cycle to DNA translocation has been unclear. Here we present the crystal structure of the E1 hexamer with single-stranded DNA discretely bound within the hexamer channel and nucleotides at the subunit interfaces. This structure demonstrates that only one strand of DNA passes through the hexamer channel and that the DNA-binding hairpins of each subunit form a spiral 'staircase' that sequentially tracks the oligonucleotide backbone. Consecutively grouped ATP, ADP and apo configurations correlate with the height of the hairpin, suggesting a straightforward DNA translocation mechanism. Each subunit sequentially progresses through ATP, ADP and apo states while the associated DNA-binding hairpin travels from the top staircase position to the bottom, escorting one nucleotide of single-stranded DNA through the channel. These events permute sequentially around the ring from one subunit to the next.

Item Type: Paper
Uncontrolled Keywords: Adenosine Diphosphate metabolism Adenosine Triphosphate metabolism Apoproteins chemistry metabolism Bovine papillomavirus 1 enzymology DNA Helicases chemistry metabolism DNA Replication DNA, Single-Stranded/chemistry/ metabolism DNA-Binding Proteins chemistry metabolism Models Molecular Nucleic Acid Conformation Protein Structure Quaternary Protein Subunits chemistry metabolism Viral Proteins chemistry metabolism
Subjects: bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > DNA translocation
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > E1 proteins
organism description > virus > papillomavirus
Investigative techniques and equipment > x ray crystallography
CSHL Authors:
Communities: CSHL labs > Joshua-Tor lab
Depositing User: CSHL Librarian
Date: 20 July 2006
Date Deposited: 15 Dec 2011 17:39
Last Modified: 05 Sep 2017 18:28
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Dataset ID:
URI: https://repository.cshl.edu/id/eprint/22787

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