| Literature DB >> 11526219 |
H Zhang1, J M Barceló, B Lee, G Kohlhagen, D B Zimonjic, N C Popescu, Y Pommier.
Abstract
Tension generated in the circular mitochondrial genome during replication and transcription points to the need for mtDNA topoisomerase activity. Here we report a 601-aa polypeptide highly homologous to nuclear topoisomerase I. The N-terminal domain of this novel topoisomerase contains a mitochondrial localization sequence and lacks a nuclear localization signal. Therefore, we refer to this polypeptide as top1mt. The pattern of top1mt expression matches the requirement for high mitochondrial activity in specific tissues. top1mt is a type IB topoisomerase that requires divalent metal (Ca(2+) or Mg(2+)) and alkaline pH for optimum activity. The TOP1mt gene is highly homologous to the nuclear TOP1 gene and consists of 14 exons. It is localized on human chromosome 8q24.3.Entities:
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Year: 2001 PMID： 11526219 PMCID： PMC58513 DOI： 10.1073/pnas.191321998
Source DB: PubMed Journal: Proc Natl Acad Sci U S A ISSN： 0027-8424 Impact factor: 11.205