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Genetic dissection of centromere function.

I G Schulman·K Bloom
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Abstract

A system to detect a minimal function of Saccharomyces cerevisiae centromeres in vivo has been developed. Centromere DNA mutants have been examined and found to be active in a plasmid copy number control assay in the absence of segregation. The experiments allow the identification of a minimal centromere unit, CDE III, independently of its ability to mediate chromosome segregation. Centromere-mediated plasmid copy number control correlates with the ability of CDE III to assemble a DNA-protein complex. Cells forced to maintain excess copies of CDE III exhibit increased loss of a nonessential artificial chromosome. Thus, segregationally impaired centromeres can have negative effects in trans on chromosome segregation. The use of a plasmid copy number control assay has allowed assembly steps preceding chromosome segregation to be defined.

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CentromereChromosome DeletionChromosomes, FungalDNA, FungalGenes, FungalMitosisMutagenesisPlasmidsRestriction MappingSaccharomyces cerevisiaeTransformation, GeneticJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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I G Schulman, K Bloom. 1993. Genetic dissection of centromere function.. https://doi.org/10.1128/mcb.13.6.3156-3166.1993

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