Methyl-directed repair of frameshift heteroduplexes in cell extracts from Escherichia coli

Brian A Learn, R. H. Grafstrom

Research output: Contribution to journalArticle

Abstract

The methyl-directed DNA repair efficiency of a series of M13mp9 frameshift heteroduplexes containing 1, 2, or 3 unpaired bases was determined by using an in vitro DNA mismatch repair assay. Repair of hemimethylated frameshift heteroduplexes in vitro was directed to the unmethylated strand; was dependent on MutH, MutL, and MutS; and was equally efficient on base insertions and deletions. However, fully methylated frameshift heteroduplexes were resistant to repair, while totally unmethylated substrates were repaired with no strand bias. Hemimethylated 1-, 2-, or 3-base insertion and deletion heteroduplexes were repaired by the methyl-directed mismatch repair pathway as efficiently as the G · T mismatch. These results are consistent with earlier in vivo studies and demonstrate the involvement of methyl-directed DNA repair in the efficient prevention of frameshift mutations.

Original languageEnglish (US)
Pages (from-to)6473-6481
Number of pages9
JournalJournal of Bacteriology
Volume171
Issue number12
StatePublished - 1989
Externally publishedYes

Fingerprint

DNA Mismatch Repair
Cell Extracts
DNA Repair
Escherichia coli
Frameshift Mutation
In Vitro Techniques

ASJC Scopus subject areas

  • Applied Microbiology and Biotechnology
  • Immunology

Cite this

Methyl-directed repair of frameshift heteroduplexes in cell extracts from Escherichia coli. / Learn, Brian A; Grafstrom, R. H.

In: Journal of Bacteriology, Vol. 171, No. 12, 1989, p. 6473-6481.

Research output: Contribution to journalArticle

@article{71d0b32e36654b5783c2dbd271e65094,
title = "Methyl-directed repair of frameshift heteroduplexes in cell extracts from Escherichia coli",
abstract = "The methyl-directed DNA repair efficiency of a series of M13mp9 frameshift heteroduplexes containing 1, 2, or 3 unpaired bases was determined by using an in vitro DNA mismatch repair assay. Repair of hemimethylated frameshift heteroduplexes in vitro was directed to the unmethylated strand; was dependent on MutH, MutL, and MutS; and was equally efficient on base insertions and deletions. However, fully methylated frameshift heteroduplexes were resistant to repair, while totally unmethylated substrates were repaired with no strand bias. Hemimethylated 1-, 2-, or 3-base insertion and deletion heteroduplexes were repaired by the methyl-directed mismatch repair pathway as efficiently as the G · T mismatch. These results are consistent with earlier in vivo studies and demonstrate the involvement of methyl-directed DNA repair in the efficient prevention of frameshift mutations.",
author = "Learn, {Brian A} and Grafstrom, {R. H.}",
year = "1989",
language = "English (US)",
volume = "171",
pages = "6473--6481",
journal = "Journal of Bacteriology",
issn = "0021-9193",
publisher = "American Society for Microbiology",
number = "12",

}

TY - JOUR

T1 - Methyl-directed repair of frameshift heteroduplexes in cell extracts from Escherichia coli

AU - Learn, Brian A

AU - Grafstrom, R. H.

PY - 1989

Y1 - 1989

N2 - The methyl-directed DNA repair efficiency of a series of M13mp9 frameshift heteroduplexes containing 1, 2, or 3 unpaired bases was determined by using an in vitro DNA mismatch repair assay. Repair of hemimethylated frameshift heteroduplexes in vitro was directed to the unmethylated strand; was dependent on MutH, MutL, and MutS; and was equally efficient on base insertions and deletions. However, fully methylated frameshift heteroduplexes were resistant to repair, while totally unmethylated substrates were repaired with no strand bias. Hemimethylated 1-, 2-, or 3-base insertion and deletion heteroduplexes were repaired by the methyl-directed mismatch repair pathway as efficiently as the G · T mismatch. These results are consistent with earlier in vivo studies and demonstrate the involvement of methyl-directed DNA repair in the efficient prevention of frameshift mutations.

AB - The methyl-directed DNA repair efficiency of a series of M13mp9 frameshift heteroduplexes containing 1, 2, or 3 unpaired bases was determined by using an in vitro DNA mismatch repair assay. Repair of hemimethylated frameshift heteroduplexes in vitro was directed to the unmethylated strand; was dependent on MutH, MutL, and MutS; and was equally efficient on base insertions and deletions. However, fully methylated frameshift heteroduplexes were resistant to repair, while totally unmethylated substrates were repaired with no strand bias. Hemimethylated 1-, 2-, or 3-base insertion and deletion heteroduplexes were repaired by the methyl-directed mismatch repair pathway as efficiently as the G · T mismatch. These results are consistent with earlier in vivo studies and demonstrate the involvement of methyl-directed DNA repair in the efficient prevention of frameshift mutations.

UR - http://www.scopus.com/inward/record.url?scp=0024358059&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024358059&partnerID=8YFLogxK

M3 - Article

C2 - 2687237

AN - SCOPUS:0024358059

VL - 171

SP - 6473

EP - 6481

JO - Journal of Bacteriology

JF - Journal of Bacteriology

SN - 0021-9193

IS - 12

ER -