RAD3 protein of Saccharomyces cerevisiae is a DNA helicase.

作者：Patrick Sung, Louise Prakash, Steven W. Matson, Satya Prakash · 发表于：Proceedings of the National Academy of Sciences · 年份：1987 · DOI：10.1073/pnas.84.24.8951 · 被引用次数：220 · 研究领域：DNA Repair Mechanisms、Carcinogens and Genotoxicity Assessment、DNA and Nucleic Acid Chemistry

The Saccharomyces cerevisiae RAD3 gene, which is required for cell viability and excision repair of damaged DNA, encodes an 89-kDa protein that has a single-stranded DNA-dependent ATPase activity. We now show that the RAD3 protein also possesses a helicase activity that unwinds duplex regions in DNA substrates constructed by annealing DNA fragments of 71-851 nucleotides to circular, single-stranded M13 DNA. The DNA helicase activity is dependent on the hydrolysis of ATP, has a pH optimum of approximately 5.6, and is inhibited by antibodies raised against a truncated RAD3 protein produced in Escherichia coli. The RAD3 helicase translocates along single-stranded DNA in the 5'----3' direction. The direction of RAD3 helicase movement is consistent with the possibility that it unwinds DNA duplexes in advance of the replication fork during DNA replication.