Dataset Information

Cloning of a marsupial DNA photolyase gene and the lack of related nucleotide sequences in placental mammals.

ABSTRACT: Photoreactivating enzyme, DNA photolyase, reduces lethal, mutagenic and carcinogenic effects of ultraviolet light (UV) by catalyzing near UV or visible light-dependent repair of cyclobutane pyrimidine dimers (CPDs) in DNA. The enzyme activity has been detected in a wide variety of organisms ranging from bacteria to nonplacental mammals. However, the evidence for photoreactivation in placental mammals, including humans, is controversial. As a first step to identify the presence and activity of the gene in mammalian species, we isolated a cDNA clone of this gene from a marsupial, the South American opossum Monodelphis domestica. Photolyase activity was expressed in Escherichia coli from the cDNA which is predicted to encode a polypeptide of 470 amino acid residues. The deduced amino acid sequence of this protein is strikingly similar to those of photolyases from two metazoans; the opossum photolyase shares 59% and 63% sequence identity with the Drosophila melanogaster and goldfish Carassius auratus enzymes, respectively. However, no closely related nucleotide sequence was detected in higher mammals and a homologous transcript was undetectable in a number of human tissues. These results strongly suggest that humans, as well as other placental mammals, lack the photolyase gene.

SUBMITTER: Kato T

PROVIDER: S-EPMC331898 | biostudies-other | 1994 Oct

REPOSITORIES: biostudies-other

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Cloning of a marsupial DNA photolyase gene and the lack of related nucleotide sequences in placental mammals.

Kato T T Todo T T Ayaki H H Ishizaki K K Morita T T Mitra S S Ikenaga M M

Nucleic acids research 19941001 20

Photoreactivating enzyme, DNA photolyase, reduces lethal, mutagenic and carcinogenic effects of ultraviolet light (UV) by catalyzing near UV or visible light-dependent repair of cyclobutane pyrimidine dimers (CPDs) in DNA. The enzyme activity has been detected in a wide variety of organisms ranging from bacteria to nonplacental mammals. However, the evidence for photoreactivation in placental mammals, including humans, is controversial. As a first step to identify the presence and activity of th ...[more]

PMID: 7937136

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Dataset Information

Cloning of a marsupial DNA photolyase gene and the lack of related nucleotide sequences in placental mammals.

Publications

Cloning of a marsupial DNA photolyase gene and the lack of related nucleotide sequences in placental mammals.

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