The Candida albicans Ku70 modulates telomere length and structure by regulating both telomerase and recombination.

TitleThe Candida albicans Ku70 modulates telomere length and structure by regulating both telomerase and recombination.
Publication TypeJournal Article
Year of Publication2011
AuthorsChico L, Ciudad T, Hsu M, Lue NF, Larriba G
JournalPLoS One
Volume6
Issue8
Paginatione23732
Date Published2011
ISSN1932-6203
KeywordsAntigens, Nuclear, Candida albicans, DNA Repair, DNA-Binding Proteins, Genotype, Ku Autoantigen, Mutation, Recombination, Genetic, Telomerase, Telomere
Abstract

The heterodimeric Ku complex has been shown to participate in DNA repair and telomere regulation in a variety of organisms. Here we report a detailed characterization of the function of Ku70 in the diploid fungal pathogen Candida albicans. Both ku70 heterozygous and homozygous deletion mutants have a wild-type colony and cellular morphology, and are not sensitive to MMS or UV light. Interestingly, we observed complex effects of KU70 gene dosage on telomere lengths, with the KU70/ku70 heterozygotes exhibiting slightly shorter telomeres, and the ku70 null strain exhibiting long and heterogeneous telomeres. Analysis of combination mutants suggests that the telomere elongation in the ku70 null mutant is due mostly to unregulated telomerase action. In addition, elevated levels of extrachromosomal telomeric circles were detected in the null mutant, consistent with activation of aberrant telomeric recombination. Altogether, our observations point to multiple mechanisms of the Ku complex in telomerase regulation and telomere protection in C. albicans, and reveal interesting similarities and differences in the mechanisms of the Ku complex in disparate systems.

DOI10.1371/journal.pone.0023732
Alternate JournalPLoS One
PubMed ID21886818
PubMed Central IDPMC3160324
Grant ListR01 GM069507 / GM / NIGMS NIH HHS / United States
GM069507 / GM / NIGMS NIH HHS / United States

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