HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology



Review

(6-4) Photolyase: Light-dependent repair of DNA damage

X. Zhao and D. Mu

Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, USA

Offprint requests to: Dr. Xiaodong Zhao, Department of Biochemistry and Biophysics, School of Medicine, CB 7260, University of North Carolina, Chapel Hill NC 27599-7260, USA. Fax: 919 966 2852. e-mail: zhaoxd@med.unc.edu

 

Summary. DNA photolyase represents a phenomenal class of DNA repair enzymes in that it harvests the light energy to repair DNA lesions caused by ultraviolet light. Mother Nature evolves two types of photolyases, one specific for repairing cyclobutane pyrimidine dimers and the other for pyrimidine-(6-4)-pyrimidone photo-products. Together, these two kinds of DNA photo-lesions account for the majority of ultraviolet light-induced DNA lesions. So far, the basic chemical steps of the enzyme mechanism of the two classes of photolyases appear to be very similar. Therefore, it will be very intersting to uncover the determinants of the different substrate specificity between the two photolyases. In this review, we focus on the discussion of the photolyase specific for repairing pyrimidine-(6-4)-pyrimidone photoproducts mainly because the research of the cyclobutane pyrimidine dimer photolyase has recently been reviewed quite extensively. Histol. Histopathol. 13, 1179-1182 (1998)

 

Key words: DNA repair, Photolyase, (6-4) photoproducts

DOI: 10.14670/HH-13.1179