[Nonhomologous mechanisms of repair of chromosomal breaks]. Progress report

Technical Report · Wed Sep 01 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/10176518· OSTI ID:10176518

Haber, J E

Broken chromosomes must either be repaired or lost. The break separates part of the chromosome, containing a telomere, from the rest, containing a centromere. While the centromerecontaining fragment can properly segregate, the broken end will be progressively degraded. The acentric fragment cannot segregate and will also be degraded. We have centered our attention on two alternative non-homologous mechanisms of repair: (1) the acquisition of a new telomere, and (2) repair of broken chromosomes by non-homologous joining of broken chromosome ends. In both cases, we create a double-strand break at a defined chromosomal location in yeast cells. The break is created by the site-specific HO endonuclease in cells that carry the rad52 mutation to prevent repair of a double-strand break by homologous recombination. In diploid cells, we can recover cells that contain a terminally deleted, healed chromosome that has acquired a new telomere. In haploid cells, we can recover cells in which the double-strand break has been repaired by rejoining the broken ends, usually accompanied by a deletion.

• Research Organization: Brandeis Univ., Waltham, MA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-91ER61235
• OSTI ID: 10176518
• Report Number(s): DOE/ER/61235--T1; ON: DE93019986
• Country of Publication: United States
• Language: English

Related Subjects

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550400
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59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOCHEMISTRY
BIOLOGICAL REPAIR
CHROMOSOMAL ABERRATIONS
DNA REPAIR
DNA SEQUENCING
GENETICS
MOLECULAR BIOLOGY
PROGRESS REPORT
RADIATION EFFECTS ON BIOCHEMICALS, CELLS, AND TISSUE CULTURE