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The Structure of Sister Minichromosome DNA Before Anaphase in <i>Saccharomyces Cerevisiae</i>

SciencePublished 18 December 1987
Douglas Koshland, Leland H. Hartwell
Citations105
SJR quartileQ1
SJR score10.42
SNIP6.62

TL;DR

The analysis of the ploidy of minichromosomes in cells that are released from arrest demonstrates that the sister molecules are properly segregated when the cell cycle block is removed.

Abstract

The role of DNA topology in holding sister chromatids together before anaphase was investigated by analyzing the structure of a small circular minichromosome in cell cycle (cdc) mutants of the yeast Saccharomyces cerevisiae. In the majority of cells arrested after S phase but before anaphase, sister minichromosome molecules are not topologically interlocked with each other. The analysis of the ploidy of minichromosomes in cells that are released from arrest demonstrates that the sister molecules are properly segregated when the cell cycle block is removed. Therefore, sister minichromosome molecules need not remain topologically interlocked until anaphase in order to be properly segregated, and topological interlocking of sister DNA molecules apparently is not the primary force holding sister chromatids together.

Keywords

Biochemistry, Genetics and Molecular Biology