MutL sliding clamps coordinate exonuclease-independent Escherichia coli mismatch repair

Jiaquan Liu, Ryanggeun Lee, Brooke M. Britton, James A. London, Keunsang Yang, Jeungphill Hanne, Jong-Bong Lee () and Richard Fishel ()
Additional contact information
Jiaquan Liu: The Ohio State University Wexner Medical Center
Ryanggeun Lee: Pohang University of Science and Technology (POSTECH)
Brooke M. Britton: The Ohio State University Wexner Medical Center
James A. London: The Ohio State University Wexner Medical Center
Keunsang Yang: School of Interdisciplinary Bioscience and Bioengineering, POSTECH
Jeungphill Hanne: The Ohio State University Wexner Medical Center
Jong-Bong Lee: Pohang University of Science and Technology (POSTECH)
Richard Fishel: The Ohio State University Wexner Medical Center

Nature Communications, 2019, vol. 10, issue 1, 1-15

Abstract: Abstract A shared paradigm of mismatch repair (MMR) across biology depicts extensive exonuclease-driven strand-specific excision that begins at a distant single-stranded DNA (ssDNA) break and proceeds back past the mismatched nucleotides. Historical reconstitution studies concluded that Escherichia coli (Ec) MMR employed EcMutS, EcMutL, EcMutH, EcUvrD, EcSSB and one of four ssDNA exonucleases to accomplish excision. Recent single-molecule images demonstrated that EcMutS and EcMutL formed cascading sliding clamps on a mismatched DNA that together assisted EcMutH in introducing ssDNA breaks at distant newly replicated GATC sites. Here we visualize the complete strand-specific excision process and find that long-lived EcMutL sliding clamps capture EcUvrD helicase near the ssDNA break, significantly increasing its unwinding processivity. EcSSB modulates the EcMutL–EcUvrD unwinding dynamics, which is rarely accompanied by extensive ssDNA exonuclease digestion. Together these observations are consistent with an exonuclease-independent MMR strand excision mechanism that relies on EcMutL–EcUvrD helicase-driven displacement of ssDNA segments between adjacent EcMutH–GATC incisions.

Date: 2019
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41467-019-13191-5 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:10:y:2019:i:1:d:10.1038_s41467-019-13191-5

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-019-13191-5

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().