cDNA clones of the human TOP1 gene encoding DNA topoisomerase I (EC 22.214.171.124) have been obtained by immunochemical screening of phage λ libraries expressing human cDNA segments, using rabbit antibodies raised against purified HeLa DNA topoisomerase I. Hybridization patterns between the cloned cDNA sequences and human cellular DNA and cytoplasmic mRNAs indicate that human TOP1 is a single-copy gene. The chromosomal location of the gene has been mapped to the long arm of chromosome 20, in the region q12-13.2, by hybridization of a radioactively labeled TOP1 cDNA probe to human metaphase chromosomes and to a panel of rodent-human somatic hybrids retaining overlapping subsets of human chromosomes.
|Number of pages||4|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|Publication status||Published - 1988|
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