Similarity among the Drosophila (6-4)photolyase, a human photolyase homolog, and the DNA photolyase-blue-light photoreceptor family.

Radiation Biology Center, Kyoto University, Kyoto, Japan.
Science (Impact Factor: 31.48). 05/1996; 272(5258):109-12.
Source: PubMed

ABSTRACT Ultraviolet light (UV)-induced DNA damage can be repaired by DNA photolyase in a light-dependent manner. Two types of photolyase are known, one specific for cyclobutane pyrimidine dimers (CPD photolyase) and another specific for pyrimidine (6-4) pyrimidone photoproducts[(6-4)photolyase]. In contrast to the CPD photolyase, which has been detected in a wide variety of organisms, the (6-4)photolyase has been found only in Drosophila melanogaster. In the present study a gene encoding the Drosophila(6-4)photolyase ws cloned, and the deduced amino acid sequence of the product was found to be similar to the CPD photolyase and to the blue-light photoreceptor of plants. A homolog of the Drosophila (6-4)photolyase gene was also cloned from human cells.

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