DNA tamirinin yüzey plazmon rezonansı ile gerçek zamanlı incelenmesi

DNA structure can be greatly affected by UV light exposure. The cyclobutane prymidine dimer (CPD) and 6-4 lesion formations along with the specific breaks on strands are the most common type of DNA damage caused by UV irradiation. Specific to UV-damaged DNA, CPD photolyase I and II construct two subfamilies of flavoproteins, and they have recognition and repair capabilities of CPD sites on both single stranded (ssDNA) and double stranded (dsDNA) DNA with the aid of blue light energy. The other types of flavoprotein family consist of cryptochromes (CRY), and the most commonly known types act as photoreceptors in plants, or circadian rhythm regulators in animals, but lack photorepair activity. Recently, it has been found that a specific type of cryptochrome also has photorepair activity on ssDNA. This protein, called cryptochrome-DASH (CRY-DASH), is yet to be studied for its binding to DNA with newly developed techniques. In this thesis, CRY-DASH-DNA interaction was investigated using Surface Plasmon Resonance (SPR) which is a common assay to characterize protein-DNA or protein-protein interactions. Next, interaction of UV damaged and undamaged DNA with CPD photolyase was then examined and compared with the interaction of damaged/undamaged DNA and CRY-DASH. SPR shows the immediate molecular binding of DNA to the surface and confirms the specific binding of photolyase and CRY-DASH with UV treated or UV untreated DNA by providing kinetic constants of binding. This study is significant for investigation of repair of lesions in the DNA structure using SPR.