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Selection and analysis of spontaneous reciprocal mitotic cross-overs in Saccharomyces cerevisiae.

ABSTRACT: We developed a system that allows the selection of the reciprocal products resulting from spontaneous mitotic cross-overs in the yeast Saccharomyces cerevisiae. A number of other types of genetic events, including chromosome loss, can be monitored with this system. For a 120-kb chromosome interval on chromosome V (CEN5-CAN1), the rate of mitotic cross-overs was 4x10(-5) per division, a rate approximately 25,000-fold lower than the meiotic rate of cross-overs. We found no suppression of mitotic cross-overs near the centromere of chromosome V, unlike the suppression observed for meiotic exchanges. The rate of reciprocal cross-overs was substantially (38-fold) elevated by treatment of cells with hydroxyurea, a drug that reduces nucleotide pools and slows DNA replication.

SUBMITTER: Barbera MA

PROVIDER: S-EPMC1550776 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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Selection and analysis of spontaneous reciprocal mitotic cross-overs in Saccharomyces cerevisiae.

Barbera Maria A MA Petes Thomas D TD

Proceedings of the National Academy of Sciences of the United States of America 20060814 34

We developed a system that allows the selection of the reciprocal products resulting from spontaneous mitotic cross-overs in the yeast Saccharomyces cerevisiae. A number of other types of genetic events, including chromosome loss, can be monitored with this system. For a 120-kb chromosome interval on chromosome V (CEN5-CAN1), the rate of mitotic cross-overs was 4x10(-5) per division, a rate approximately 25,000-fold lower than the meiotic rate of cross-overs. We found no suppression of mitotic c ...[more]

PMID: 16908833

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