Telomerase-null survivor screening identifies novel telomere recombination regulators.
PLoS Genet
; 9(1): e1003208, 2013.
Article
em En
| MEDLINE
| ID: mdl-23390378
ABSTRACT
Telomeres are protein-DNA structures found at the ends of linear chromosomes and are crucial for genome integrity. Telomeric DNA length is primarily maintained by the enzyme telomerase. Cells lacking telomerase will undergo senescence when telomeres become critically short. In Saccharomyces cerevisiae, a very small percentage of cells lacking telomerase can remain viable by lengthening telomeres via two distinct homologous recombination pathways. These "survivor" cells are classified as either Type I or Type II, with each class of survivor possessing distinct telomeric DNA structures and genetic requirements. To elucidate the regulatory pathways contributing to survivor generation, we knocked out the telomerase RNA gene TLC1 in 280 telomere-length-maintenance (TLM) gene mutants and examined telomere structures in post-senescent survivors. We uncovered new functional roles for 10 genes that affect the emerging ratio of Type I versus Type II survivors and 22 genes that are required for Type II survivor generation. We further verified that Pif1 helicase was required for Type I recombination and that the INO80 chromatin remodeling complex greatly affected the emerging frequency of Type I survivors. Finally, we found the Rad6-mediated ubiquitination pathway and the KEOPS complex were required for Type II recombination. Our data provide an independent line of evidence supporting the idea that these genes play important roles in telomere dynamics.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Saccharomyces cerevisiae
/
DNA Helicases
/
Telomerase
/
Proteínas de Saccharomyces cerevisiae
/
Recombinação Homóloga
Tipo de estudo:
Diagnostic_studies
/
Screening_studies
Idioma:
En
Revista:
PLoS Genet
Assunto da revista:
GENETICA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
China