Effect of colchicine & methylated purines on UV-induced mitotic gene conversion in Saccharomyces cerevisiae
Vashishat, R.K.; Kaushal, B.
Indian Journal of Experimental Biology 21(7): 367-370
1983
ISSN/ISBN: 0019-5189 PMID: 6365750 Document Number: 212377
Effects of photoreactivation, inhibition of chromosome pairing by colchicine and that of recombinational repair by methylated purines (caffeine, theophylline and theobromine) were studied on UV-induced mitotic gene conversion in D-strain of S. cerevisiae. Photoreactivation increased UV-survival and reduced the frequency of UV-induced gene convertants. The presence of colchicine in the post-irradiation growth media reduced survival and the frequency of UV-induced convertants. Supplementation of post-irradiation growth media with any of the methylated purines decreased UV-survival and frequency of induced convertants. Inhibition of DNA synthesis by UV-induced pyrimidine dimers may bring about mitotic pairing of homologous chromosomes and this pairing may lead to hybrid DNA formation and subsequent recombination. A part of UV-induced mitotic recombination is dependent on functional recombinational repair of UV-damage.