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A non-canonical function of topoisomerase II in disentangling dysfunctional telomeres.

ABSTRACT: The decatenation activity of topoisomerase II (Top2), which is widely conserved within the eukaryotic domain, is essential for chromosomal segregation in mitosis. It is less clear, however, whether Top2 performs the same function uniformly across the whole genome, and whether all its functions rely on decatenation. In the fission yeast, Schizosaccharomyces pombe, telomeres are bound by Taz1, which promotes smooth replication fork progression through the repetitive telomeric sequences. Hence, replication forks stall at taz1 Delta telomeres. This leads to telomeric entanglements at low temperatures (

SUBMITTER: Germe T

PROVIDER: S-EPMC2750024 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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A non-canonical function of topoisomerase II in disentangling dysfunctional telomeres.

Germe Thomas T Miller Kyle K Cooper Julia Promisel JP

The EMBO journal 20090813 18

The decatenation activity of topoisomerase II (Top2), which is widely conserved within the eukaryotic domain, is essential for chromosomal segregation in mitosis. It is less clear, however, whether Top2 performs the same function uniformly across the whole genome, and whether all its functions rely on decatenation. In the fission yeast, Schizosaccharomyces pombe, telomeres are bound by Taz1, which promotes smooth replication fork progression through the repetitive telomeric sequences. Hence, rep ...[more]

PMID: 19680223

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