Linked Life Data

2191957

Source:http://linkedlifedata.com/resource/pubmed/id/2191957

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1990-7-26
pubmed:abstractText
The frequency of replication initiation of the ColIb-P9 plasmid depends on the level of repZ expression, which has been shown to be negatively regulated by inc RNA, the approximately 70-base-long product of the inc gene. To further understand the regulatory mechanism of repZ gene expression, we isolated mutants defective in ColIb-P9 replication using a lambda:ColIb-P9 hybrid phage. Among six mutants isolated, one amber mutant, rep57, failed to synthesize the RepZ protein. The mutation occurred in the repZ leader sequence that encodes a 29-amino-acid reading frame, designated as repY. We also isolated mutants that suppressed the rep57 phenotype. These mutations were single base insertions between the repY initiation codon and the rep57 mutation site and resulted not only in a frame shift of repY but also in the formation of repY-repZ fusions without changing the amino acid sequence of RepZ. Thus, repY is not directly involved in the replication reaction but rather functions as a positive regulator for repZ expression. We propose that repZ expression is coupled with repY translation, which acts to disrupt a secondary structure sequestering the repZ translation initiation signal. The positive and negative regulations of repZ expression were discussed. The other mutants were mapped in repZ, confirming that repZ is essential for ColIb-P9 replication.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10666-73
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Role of leader peptide synthesis in repZ gene expression of the ColIb-P9 plasmid.
pubmed:affiliation
Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't