Determination of cytosine-cytosine photodimers in the DNA of Cloudman S91 melanoma cells using high pressure liquid chromatography.
I measured the induction of cytosine-cytosine dimer (C-C) densities after UV-C (less than 290 nm) and UV-B irradiation (290-320 nm) in the 2'-deoxy-[3H]cytidine labeled DNA of Cloudman S91 mouse melanoma cells using a new, sensitive high pressure liquid chromatography procedure. UV-B exposure resulted in 0.000034% C-C/J m-2 of the total cytosine radioactivity which is 10 times less than the rate during UV-C irradiation. Previous work with these melanoma cells showed a 4-fold lower rate of induction of thymine-containing pyrimidine dimers by UV-B than UV-C light (Niggli Photochem. Photobiol. 52, 519-524, 1990). Based on these results, the calculated ratios for the pyrimidine dimer subspecies showed no significant difference following UV-C and UV-B exposure. However, UV-C and UV-B light induce 10-20 times more thymine-containing pyrimidine dimers than C-C in the DNA of S91 cells.
Niggli
H J
HJ
Cosmital SA, Marly, Switzerland.
D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003596:Cytosine / Q000032:analysis / Q000528:radiation effects; D004273:DNA, Neoplasm / Q000032:analysis / Q000528:radiation effects; D008546:Melanoma, Experimental / Q000737:chemistry; D011740:Pyrimidine Dimers / Q000032:analysis* / Q000528:radiation effects; D014466:Ultraviolet Rays
D004273:DNA, Neoplasm; D011740:Pyrimidine Dimers; D003596:Cytosine