The restriction endonuclease AluI induces sister chromatid exchange in Chinese hamster ovary cells.
Chinese hamster ovary (CHO) cells were exposed to the restriction endonuclease AluI in the presence of 1.1 M glycerol. Chromosomal aberrations and sister chromatid exchange (SCE) were scored in first post-treatment metaphases following recovery times of 6-18 h. At all recovery times chromosomal aberrations were induced by the enzyme. In AluI-treated damaged cells significant elevations of SCE frequencies were found after recovery times of 12-18 h. These results indicate that SCE, unlike chromosomal aberrations, are induced only in late G1 and early S phase of the cell cycle. The lesions producing SCE are postulated as DNA single-strand breaks and gaps induced by AluI in canonical structures of DNA and in DNA-RNA hybrids.
Folle
G A
GA
Department of Genetics, Universität GH Essen, FRG.
Johannes
C
C
Mechoso
B H
BH
Medina
I I
II
Obe
G
G
D000818:Animals; D016466:CHO Cells; D002869:Chromosome Aberrations / Q000235:genetics; D006224:Cricetinae; D015252:Deoxyribonucleases, Type II Site-Specific / Q000494:pharmacology*; D005260:Female; D016193:G1 Phase / Q000187:drug effects*; D010053:Ovary / Q000187:drug effects*; D016196:S Phase / Q000187:drug effects*; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D013997:Time Factors
C024669:endodeoxyribonuclease AluI; D015252:Deoxyribonucleases, Type II Site-Specific