title: Cloning, characterization, and sequence of the yeast DNA topoisomerase I gene.
abstract: The structural gene for yeast DNA topoisomerase I (TOP1) has been cloned from two yeast genomic plasmid banks. Integration of a plasmid carrying the gene into the chromosome and subsequent genetic mapping shows that TOP1 is identical to the gene previously called MAK1. Seven top1 (mak1) mutants including gene disruptions are viable, demonstrating that DNA topoisomerase I is not essential for viability in yeast. A 3787-base-pair DNA fragment including the gene has been sequenced. The protein predicted from the DNA sequence has 769 amino acids and a molecular weight of 90,020.
authors.forename: C
authors.initials: C
authors.lastname: Thrash
authors.forename: A T
authors.initials: AT
authors.lastname: Bankier
authors.forename: B G
authors.initials: BG
authors.lastname: Barrell
authors.forename: R
authors.initials: R
authors.lastname: Sternglanz
mesh_terms: D001483:Base Sequence; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004264:DNA Topoisomerases, Type I / Q000235:genetics*; D015247:Deoxyribonuclease HindIII; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000235:genetics; D005796:Genes; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics
chemical_list: D004262:DNA Restriction Enzymes; D015247:Deoxyribonuclease HindIII; D004264:DNA Topoisomerases, Type I