Photochemistry of psoralen-DNA adducts, biological effects of psoralen-DNA adducts, applications of psoralen-DNA photochemistry

Abstract

This thesis czr.sists of three main parts and totally eight ohacters. Ir. part I, I will present studies en the photochemistry ::psoraler.-DIIA adducts, specifically, the wavelength dependencies f:r the phot:reversals cf thyraidine-riMT (4' -hydrcxymethyi-4, :', 3-trir.er.thyipsoraien) mcr.cadducts and diadduct and the sarr.e adoucts incorporated in DMA helloes and the wavelength decer.decies for the ph:-ccorcsslir.kir.g cf thymidine-HMT mcr.cadducts in dcuhie-stranded helloes.In part II, I will report seme biological effects of psoralen-:;:".-, aiduccs, i.e., the effects on double-stranded DMA stability, DNA struoture, and transcription by E. coli and T7 RNA polymerases. Finally, Iwill focus on the applications of psoralen-DMA photochemistry to inves tigation cf protein-DIiA interaction during transcription, which includes the interaction cf E. coli and T7 RNA polymerases with D:;A in elongation complexes arrested at specific pscraien-DHA acduct sites as revealed by DMase I foctprinting experiments. DEDICATIONThis work is dedicated to Theresa Ng.