ISSN:
1617-4623
Keywords:
Saccharomyces cerevisiae
;
2 μm circle
;
Plasmid-partitioning
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The yeast 2 μm circle encodes four major transcribed open reading frames, A, B, C and D. Products of ORF's A, B and C, together with the inverted repeats and the other cis-acting loci ORI and STB, have been shown to be involved in plasmid maintenance. However, the function of ORF D has remained unclear. We have therefore carried out studies on 2 μm derivatives with both insertional and frameshift mutations in D. Our results indicate that there is a protein product encoded by ORF D, which is involved in plasmid maintenance. When the copy number of the C gene was reduced to one, by chromosomal integration, we observed striking differences in the efficiency of partitioning of D + and D − plasmid derivatives. Absence of D function could be compensated by an increase in dosage of the C gene, indicating that the D product may act to regulate C expression. Since the C product has been implicated in copy number control as well as partitioning, our data suggest that the D product may also be involved in both of these processes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00330846
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