Human DNA ligase I cDNA: cloning and functional expression in Saccharomyces cerevisiae.
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Barnes DE, Johnston LH, Kodama K, Tomkinson AE, Lasko DD, Lindahl T
Human DNA ligase I cDNA: cloning and functional expression in Saccharomyces cerevisiae.
Proc Natl Acad Sci U S A. 1990 Sep;87(17):6679-83.
- PubMed ID
- 2204063 [ View in PubMed]
- Abstract
Human cDNA clones encoding the major DNA ligase activity in proliferating cells, DNA ligase I, were isolated by two independent methods. In one approach, a human cDNA library was screened by hybridization with oligonucleotides deduced from partial amino acid sequence of purified bovine DNA ligase I. In an alternative approach, a human cDNA library was screened for functional expression of a polypeptide able to complement a cdc9 temperature-sensitive DNA ligase mutant of Saccharomyces cerevisiae. The sequence of an apparently full-length cDNA encodes a 102-kDa protein, indistinguishable in size from authentic human DNA ligase I. The deduced amino acid sequence of the human DNA ligase I cDNA is 40% homologous to the smaller DNA ligases of S. cerevisiae and Schizosaccharomyces pombe, homology being confined to the carboxyl-terminal regions of the respective proteins. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is transcribed from a single-copy gene on chromosome 19.