Properties of REP3: a cis-acting locus required for stable propagation of the Saccharomyces cerevisiae plasmid 2 microns circle.

AUTOR(ES)

Jayaram, M

RESUMO

Stable propagation of the yeast plasmid 2 microns requires an origin of replication, a cis-active locus designated REP3, and two plasmid-encoded proteins which are the products of the REP1 and REP2 genes. The three REP loci appear to constitute a partitioning system, ensuring equal distribution of plasmid molecules to mother and daughter cells after mitosis. We have localized the REP3 site completely within a segment of five-and-one-half direct tandem repeats of a 62-base-pair unit, bordered by HpaI and AvaI restriction sites within the large unique region of the 2 microns genome. In addition, we find that the repeated elements are functionally distinct. Only a subset of the repeats is necessary to promote full partitioning activity. The other repeats appear to promote plasmid transcription. These results are discussed in the context of a model of plasmid copy control involving titration of a plasmid-specific protein by the repeated elements within REP3.

Documentos Relacionados

• Identification of the crossover site during FLP-mediated recombination in the Saccharomyces cerevisiae plasmid 2 microns circle.
• Identification of cis-acting elements in the SUC2 promoter of Saccharomyces cerevisiae required for activation of transcription.
• A CIS-Acting Mutation within the MATa Locus of SACCHAROMYCES CEREVISIAE That Prevents Efficient Homothallic Mating-Type Switching
• Signals for transcription initiation and termination in the Saccharomyces cerevisiae plasmid 2 micron circle.
• Maintenance of the 2 microns circle plasmid in populations of Saccharomyces cerevisiae.