Linked Life Data

2527304

Source:http://linkedlifedata.com/resource/pubmed/id/2527304

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1989-9-18
pubmed:abstractText
In the accompanying paper, RecA142 protein was found to be completely defective in DNA heteroduplex formation. Here, we show that RecA142 protein not only is defective in this activity but also is inhibitory for certain activities of wild-type RecA protein. Under appropriate conditions, RecA142 protein substantially inhibits the DNA strand exchange reaction catalyzed by wild-type RecA protein; at equimolar concentrations of each protein, formation of full-length gapped duplex DNA product molecules is less than 7% of the amount produced by wild-type protein alone. Inhibition by RecA142 protein is also evident in S1 nuclease assays of DNA heteroduplex formation, although the extent of inhibition is less than is observed for the complete DNA strand exchange process; at equimolar concentrations of wild-type and mutant proteins, the extent of DNA heteroduplex formation is 36% of the wild-type protein level. This difference implies that RecA142 protein prevents, at minimum, the branch migration normally observed during DNA strand exchange. RecA142 protein does not inhibit either the single-strand (ss) DNA-dependent ATPase activity or the coaggregation activities of wild-type RecA protein. This suggests that these reactions are not responsible for the inhibition of wild-type protein DNA strand exchange activity by RecA142 protein. However, under conditions where RecA142 protein inhibits DNA strand exchange activity, RecA142 protein renders the M13 ssDNA-dependent ATPase activity of wild-type protein sensitive to inhibition by single-strand DNA-binding protein, and it inhibits the double-strand DNA-dependent ATPase activity of wild-type RecA protein. These results imply that these two activities are important components of the overall DNA strand exchange process. These experiments also demonstrate the applicability of using defective mutant RecA proteins as specific codominant inhibitors of wild-type protein activities in vitro and should be of general utility for mechanistic analysis of RecA protein function both in vitro and in vivo.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
207
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
735-47
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Biochemical events essential to the recombination activity of Escherichia coli RecA protein. II. Co-dominant effects of RecA142 protein on wild-type RecA protein function.
pubmed:affiliation
Department of Molecular Biology, Northwestern University Medical School, Chicago, IL 60611.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't