Human NEIL1 localizes with the centrosomes and condensed chromosomes during mitosis

Chromatin remodelling complex RSC promotes base excision repair in chromatin of Saccharomyces cerevisiae

The base excision repair (BER) pathway is a conserved DNA repair system required to maintain genomic integrity and prevent mutagenesis in all eukaryotic cells. Nevertheless, how BER operates in vivo (i.e. in the context of chromatin) is poorly understood. We have investigated the role of an essential ATP-dependent chromatin remodelling (ACR) complex RSC (Remodels the Structure of Chromatin) in BER of intact yeast cells. We show that depletion of STH1, the ATPase subunit of RSC, causes enhanced sensitivity to the DNA alkylating agent methyl methanesulfonate (MMS) and results in a substantial inhibition of BER, at the GAL1 locus and in the genome overall. Consistent with this observation, the DNA in chromatin is less accessible to micrococcal nuclease digestion in the absence of RSC. Quantitative PCR results indicate that repair deficiency in STH1 depleted cells is not due to changes in the expression of BER genes. Collectively, our data indicates the RSC complex promotes efficient BER in chromatin. These results provide, for the first time, a link between ATP-dependent chromatin remodelling and BER in living cells.

Regulation of DNA glycosylases and their role in limiting disease

This review will present a current understanding of mechanisms for the initiation of base excision repair (BER) of oxidatively-induced DNA damage and the biological consequences of deficiencies in these enzymes in mouse model systems and human populations.