The Cockayne Syndrome Group B Gene Product is Involved in Cellular Repair of 8-Hydroxyadenine in DNA

Published

August 23, 2002

Author(s)

J Tuo, Pawel Jaruga, H Rodriguez, Miral M. Dizdar, V. Bohr

Abstract

Cockayne syndrome (CS) is a human disease characterized by sensitivity to sunlight, severe neurological abnormalities and accelerated aging. CS has two complementation groups, CS-A and CS-B. The CSB gene encodes the CSB protein with 1493 amino acids. We previously reported that the CSB protein is involved in cellular repair of 8-hydroxyguanine, an abundant lesion in oxidatively damaged DNA, and that the putative helicase motif V/VI of the CSB may play a role in this process. The present study investigated the role of the CSB protein in cellular repair of 8-hydroxyadenine, another abundant lesion in oxidatively damaged DNA. Extracts of CS-B null cells and mutant cells with site-directed mutation in the motif VI of the putative helicase domain incised 8-hydroxyadenine in vitro less efficiently than wild type cells. Furthermore, CS-B null and motif VI mutant cells accumulated more 8-hydroxyadenine in their genomic DNA than wild type cells after exposure to γ-radiation at doses of 2 or 5 Gy. These results suggest that the CSB protein contributes to cellular repair of 8-OH-Ade, and that the motif VI of the putative helicase domain of CSB is required by this activity.

Citation

Journal of Biological Chemistry

Volume

277

Issue

34

Pub Type

Journals

Keywords

8-hydroxyadenine, cockayne syndrome, DNA repair, liquid chromatography/mass spectrometry, oxidative DNA damage

Citation

Tuo, J. , Jaruga, P. , Rodriguez, H. , Dizdar, M. and Bohr, V. (2002), The Cockayne Syndrome Group B Gene Product is Involved in Cellular Repair of 8-Hydroxyadenine in DNA, Journal of Biological Chemistry (Accessed October 24, 2025)