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SepBCTF4 is required for the formation of DNA-damage-induced UvsCRAD51 foci in Aspergillus nidulans.

ABSTRACT: SepB is an essential, conserved protein required for chromosomal DNA metabolism in Aspergillus nidulans. Homologs of SepB include yeast Ctf4p and human hAnd-1. Molecular and bioinformatic characterization of these proteins suggests that they act as molecular scaffolds. Furthermore, recent observations implicate the yeast family members in lagging-strand replication and the establishment of sister-chromatid cohesion. Here, we demonstrate that SepB functions in the A. nidulans DNA damage response. In particular, analysis of double mutants reveals that SepB is a member of the UvsC(RAD51) epistasis group. In accord with this prediction, we show that UvsC(RAD51) forms DNA-damage-induced nuclear foci in a manner that requires SepB function. We also provide evidence that implicates SepB in sister-chromatid cohesion, thereby suggesting that cohesion may play a role in regulating the localization and/or assembly of UvsC(RAD51) complexes.

SUBMITTER: Gygax SE

PROVIDER: S-EPMC1449558 | biostudies-literature | 2005 Mar

REPOSITORIES: biostudies-literature

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SepBCTF4 is required for the formation of DNA-damage-induced UvsCRAD51 foci in Aspergillus nidulans.

Gygax Scott E SE Semighini Camile P CP Goldman Gustavo H GH Harris Steven D SD

Genetics 20050116 3

SepB is an essential, conserved protein required for chromosomal DNA metabolism in Aspergillus nidulans. Homologs of SepB include yeast Ctf4p and human hAnd-1. Molecular and bioinformatic characterization of these proteins suggests that they act as molecular scaffolds. Furthermore, recent observations implicate the yeast family members in lagging-strand replication and the establishment of sister-chromatid cohesion. Here, we demonstrate that SepB functions in the A. nidulans DNA damage response. ...[more]

PMID: 15654119

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