Use of a ring chromosome and pulsed-field gels to study interhomolog recombination, double-strand DNA breaks and sister-chromatid exchange in yeast

Journal Article · Fri Dec 01 04:00:00 EST 1989 · Genetics; (USA)

OSTI ID:6647559

Game, J C ^[1]; Sitney, K C; Cook, V E; Mortimer, R K ^[2]

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1. Lawrence Berkeley Lab., CA (USA)
2. Univ. of California, Berkeley (USA)

The authors describe a system that uses pulsed-field gels for the physical detection of recombinant DNA molecules, double-strand DNA breaks (DSB) and sister-chromatid exchange in the yeast Saccharomyces cerevisiae. The system makes use of a circular variant of chromosome II (Chr. III). Meiotic recombination between this ring chromosome and a linear homolog produces new molecules of sizes distinguishable on gels from either parental molecule. They demonstrate that these recombinant molecules are not present either in strains with two linear Chr. III molecules or in rad50 mutants, which are defective in meiotic recombination. In conjunction with the molecular endpoints. They present data on the timing of commitment to meiotic recombination scored genetically. They have used x-rays to linearize circular Chr. III, both to develop a sensitive method for measuring frequency of DSB and as a means of detecting double-size circles originating in part from sister-chromatid exchange, which they find to be frequent during meiosis.

• OSTI ID: 6647559
• Journal Information: Genetics; (USA), Journal Name: Genetics; (USA) Vol. 123:4; ISSN 0016-6731; ISSN GENTA
• Country of Publication: United States
• Language: English

Related Subjects

560130* -- Radiation Effects on Microorganisms
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CELL DIVISION
CHROMOSOMAL ABERRATIONS
CHROMOSOMES
ELECTROMAGNETIC RADIATION
ELECTROPHORESIS
EUMYCOTA
FUNGI
GENE RECOMBINATION
IONIZING RADIATIONS
MEIOSIS
MICROORGANISMS
MUTATION FREQUENCY
MUTATIONS
PLANTS
RADIATIONS
RADIOINDUCTION
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
SISTER CHROMATID EXCHANGES
STRAND BREAKS
X RADIATION
YEASTS