Suppression of Cyclobutane and <6-4> Dipyrimidines Formation in Triple-Stranded H-DNA
Abstract
We have determined the effect of H-DNA formation on the distributions of two ultraviolet (UV) light induced photoproducts-cyclobutane dipyrimidines and <6-4> dipyrimidines. A region of DNA containing the sequence (dT-dC)_(18)^*(dA-dG)_(18) was treated under conditions that specifically yield the triple-stranded H-y3 or H-y5 DNA structure and then irradiated with UV. The positions of cyclobutane dipyrimidines and <6-4> dipyrimidines were determined by T4 endonuclease V cleavage and by hot piperidine cleavage, respectively. Formation of H-DNA structures greatly decreased the photoproduct yield in the (dT-dC)_(18)^*(dA-dG)_(18) region but not elsewhere in the DNA. Suppression of photoproduct formation is greater in half of the repeat, reflecting whether the DNA is in the H-y3 or H-y5 conformation. Within the repeat, the suppression was less in the middle and toward the ends. Models for the suppression of photoproduct formation in H-DNA and the possible utility of our findings are discussed.
Additional Information
© 1991 American Chemical Society. Published in print 16 July 1991. This research was supported by US. Public Health Service Grants ES 03124 and CA 42897 (MA T.) and GM 30220 (J.E.D.); Y. C. was supported by a grant of a gift from the Lucille P. Markey Charitable Trust, and H.H. was supported by an NIH postdoctoral fellowship (GM 14220). We thank Mr. B. Alderete and Dr. J. Pierce for their excellent technical assistance and Drs. M. Nazimeic, M. Patrick, and J. Pierce for their critical review of the manuscript.Additional details
- Eprint ID
- 84788
- DOI
- 10.1021/bi00242a030
- Resolver ID
- CaltechAUTHORS:20180212-101922604
- ES 03124
- NIH
- CA 42897
- NIH
- GM 30220
- NIH
- Lucille P. Markey Charitable Trust
- GM 14220
- NIH Postdoctoral Fellowship
- Created
-
2018-02-13Created from EPrint's datestamp field
- Updated
-
2021-11-15Created from EPrint's last_modified field