Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-6-1
pubmed:databankReference
pubmed:abstractText
The plasmid-partition regions of the P1 and P7 plasmid prophages in Escherichia coli are homologues which each encode two partition proteins, ParA and ParB. The equivalent P1 and P7 proteins are closely related. In each case, the proteins are encoded by an operon that is autoregulated by the ParA and ParB proteins in concert. This regulation is species-specific, as the P1 proteins are unable to repress the P7 par operon and vice versa. The homologous ParA proteins are primarily responsible for repression and bind to regions that overlap the operon promoter in both cases. The DNA-binding domain of the P7 autorepressor lies in the amino-terminal end of the P7 ParA protein. This region includes a helix-turn-helix motif that has a clear counterpart in the P1 ParA sequence. However, despite the common regulatory mechanism and the similarity of the proteins involved in repression, the promoter-operator sequences of these two operons are very different in sequence and organization. The operator is located downstream of the promoter in P1 and upstream of it in P7, and the two regions show little, if any, homology. How these differences may have arisen from a common ancestral form is discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:geneSymbol
lacZ, parA, parB
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
249-60
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:8170387-Amino Acid Sequence, pubmed-meshheading:8170387-Bacterial Proteins, pubmed-meshheading:8170387-Base Sequence, pubmed-meshheading:8170387-Cloning, Molecular, pubmed-meshheading:8170387-Coliphages, pubmed-meshheading:8170387-DNA Mutational Analysis, pubmed-meshheading:8170387-Escherichia coli, pubmed-meshheading:8170387-Gene Expression Regulation, Bacterial, pubmed-meshheading:8170387-Genes, Bacterial, pubmed-meshheading:8170387-Molecular Sequence Data, pubmed-meshheading:8170387-Operon, pubmed-meshheading:8170387-Plasmids, pubmed-meshheading:8170387-Polymerase Chain Reaction, pubmed-meshheading:8170387-Promoter Regions, Genetic, pubmed-meshheading:8170387-Repressor Proteins, pubmed-meshheading:8170387-Restriction Mapping, pubmed-meshheading:8170387-Sequence Homology, Nucleic Acid, pubmed-meshheading:8170387-beta-Galactosidase
pubmed:year
1994
pubmed:articleTitle
The homologous operons for P1 and P7 plasmid partition are autoregulated from dissimilar operator sites.
pubmed:affiliation
Laboratory of Chromosome Biology, ABL-Basic Research Program, NCI-Frederick Cancer Research and Development Center, Maryland 21702.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.