Gap formation is associated with methyl-directed mismatch correction under conditions of restricted DNA synthesis.
Journal Article (Journal Article)
A covalently closed, circular heteroduplex containing a G-T mismatch and a single hemimethylated d(GATC) site is subject to efficient methyl-directed mismatch correction in Escherichia coli extracts when repair DNA synthesis is severely restricted by limiting the concentration of exogenously supplied deoxyribonucleoside-5'-triphosphates or by supplementing reactions with chain-terminating 2',3'-dideoxynucleoside triphosphates. However, repair under these conditions results in formation of a single-strand gap in the region of the molecule containing the mismatch and the d(GATC) site. These findings indicate that repair DNA synthesis required for methyl-directed correction can initiate in the vicinity of the mispair, and they are most consistent with a repair reaction involving 3'----5' excision (or strand displacement) from the d(GATC) site followed by 5'----3' repair DNA synthesis initiating in the vicinity of the mismatch.
Full Text
Duke Authors
Cited Authors
- Su, SS; Grilley, M; Thresher, R; Griffith, J; Modrich, P
Published Date
- 1989
Published In
Volume / Issue
- 31 / 1
Start / End Page
- 104 - 111
PubMed ID
- 2687086
Pubmed Central ID
- 2687086
International Standard Serial Number (ISSN)
- 0831-2796
Digital Object Identifier (DOI)
- 10.1139/g89-020
Language
- eng
Conference Location
- Canada