Distinct Requirements within the Msh3 Nucleotide Binding Pocket for Mismatch and Double-Strand Break Repair

Distinct Requirements within the Msh3 Nucleotide Binding Pocket for Mismatch and Double-Strand... In Saccharomyces cerevisiae, repair of insertion/deletion loops is carried out by Msh2–Msh3-mediated mismatch repair (MMR). Msh2–Msh3 is also required for 3′ non-homologous tail removal (3′ NHTR) in double-strand break repair. In both pathways, Msh2–Msh3 binds double-strand/single-strand junctions and initiates repair in an ATP-dependent manner. However, the kinetics of the two processes appear different; MMR is likely rapid in order to coordinate with the replication fork, whereas 3′ NHTR has been shown to be a slower process. To understand the molecular requirements in both repair pathways, we performed an in vivo analysis of well-conserved residues in Msh3 that are hypothesized to be required for MMR and/or 3′ NHTR. These residues are predicted to be involved in either communication between the DNA-binding and ATPase domains within the complex or nucleotide binding and/or exchange within Msh2–Msh3. We identified a set of aromatic residues within the FLY motif of the predicted Msh3 nucleotide binding pocket that are essential for Msh2–Msh3-mediated MMR but are largely dispensable for 3′ NHTR. In contrast, mutations in other regions gave similar phenotypes in both assays. Based on these results, we suggest that the two pathways have distinct requirements with respect to the position of the bound ATP within Msh3. We propose that the differences are related, at least in part, to the kinetics of each pathway. Proper binding and positioning of ATP is required to induce rapid conformational changes at the replication fork, but is less important when more time is available for repair, as in 3′ NHTR. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Molecular Biology Elsevier

Distinct Requirements within the Msh3 Nucleotide Binding Pocket for Mismatch and Double-Strand Break Repair

Loading next page...
 
/lp/elsevier/distinct-requirements-within-the-msh3-nucleotide-binding-pocket-for-hrvIRVtAan
Publisher
Academic Press
Copyright
Copyright © 2013 Elsevier Ltd
ISSN
0022-2836
D.O.I.
10.1016/j.jmb.2013.02.024
Publisher site
See Article on Publisher Site

Abstract

In Saccharomyces cerevisiae, repair of insertion/deletion loops is carried out by Msh2–Msh3-mediated mismatch repair (MMR). Msh2–Msh3 is also required for 3′ non-homologous tail removal (3′ NHTR) in double-strand break repair. In both pathways, Msh2–Msh3 binds double-strand/single-strand junctions and initiates repair in an ATP-dependent manner. However, the kinetics of the two processes appear different; MMR is likely rapid in order to coordinate with the replication fork, whereas 3′ NHTR has been shown to be a slower process. To understand the molecular requirements in both repair pathways, we performed an in vivo analysis of well-conserved residues in Msh3 that are hypothesized to be required for MMR and/or 3′ NHTR. These residues are predicted to be involved in either communication between the DNA-binding and ATPase domains within the complex or nucleotide binding and/or exchange within Msh2–Msh3. We identified a set of aromatic residues within the FLY motif of the predicted Msh3 nucleotide binding pocket that are essential for Msh2–Msh3-mediated MMR but are largely dispensable for 3′ NHTR. In contrast, mutations in other regions gave similar phenotypes in both assays. Based on these results, we suggest that the two pathways have distinct requirements with respect to the position of the bound ATP within Msh3. We propose that the differences are related, at least in part, to the kinetics of each pathway. Proper binding and positioning of ATP is required to induce rapid conformational changes at the replication fork, but is less important when more time is available for repair, as in 3′ NHTR.

Journal

Journal of Molecular BiologyElsevier

Published: Jun 12, 2013

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off