Synergistic effect of DAPI and thymidylate stress conditions on the induction of common fragile sites.
When supplied to human leukocytes grown in complete medium (RPMI 1640), DAPI, a nonintercalating compound specific for the AT bases of DNA, induces the appearance of three common fragile sites (CFRA) mapped at 1q42, 2q31, and 7p22. The same treatment with DAPI in a medium deficient in folic acid and thymidine (199 M) considerably increases the expression of these sites and induces the appearance of a further 16 CFRA sites at 1q24, 2p25, 4p16, 4q25, 5p15.3, 6p21.3, 6p25, 6q13, 9p24, 16p13.3, 16q23, 17q21, 18q23, 20q13.1, 21q21, and Xq28. The results point to the existence of a synergism between DAPI and thymidylate-stress culture conditions in inducing site-specific chromosome damage. The results also agree with the hypothesis that DAPI-induced CFRA sites are DNA late-replicating chromosomal areas rich in AT bases.
Rocchi
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A
Dipartimento di Genetica e Biologia Molecolare, Università La Sapienza, Rome, Italy.
Pelliccia
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F
D002478:Cells, Cultured; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D003470:Culture Media; D005260:Female; D005456:Fluorescent Dyes / Q000494:pharmacology*; D005492:Folic Acid; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D008214:Lymphocytes / Q000187:drug effects*; D008297:Male; D013936:Thymidine
D003470:Culture Media; D005456:Fluorescent Dyes; D007211:Indoles; C007293:DAPI; D005492:Folic Acid; D013936:Thymidine