Rap1 protein regulates telomere turnover in yeast
AUTOR(ES)
Krauskopf, Anat
FONTE
The National Academy of Sciences
RESUMO
Telomere length is maintained through a dynamic balance between addition and loss of the terminal telomeric DNA. Normal telomere length regulation requires telomerase as well as a telomeric protein–DNA complex. Previous work has provided evidence that in the budding yeasts Kluyveromyces lactis and Saccharomyces cerevisiae, the telomeric double-stranded DNA binding protein Rap1p negatively regulates telomere length, in part by nucleating, by its C-terminal tail, a higher-order DNA binding protein complex that presumably limits access of telomerase to the chromosome end. Here we show that in K. lactis, truncating the Rap1p C-terminal tail (Rap1p-ΔC mutant) accelerates telomeric repeat turnover in the distal region of the telomere. In addition, combining the rap1-ΔC mutation with a telomerase template mutation (ter1-kpn), which directs the addition of mutated telomeric DNA repeats to telomeres, synergistically caused an immediate loss of telomere length regulation. Capping of the unregulated telomeres of these double mutants with functionally wild-type repeats restored telomere length control. We propose that the rate of terminal telomere turnover is controlled by Rap1p specifically through its interactions with the most distal telomeric repeats.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=22857Documentos Relacionados
- RAP1 stimulates single- to double-strand association of yeast telomeric DNA: implications for telomere-telomere interactions.
- The yeast telomere-binding protein RAP1 binds to and promotes the formation of DNA quadruplexes in telomeric DNA.
- Trapping Rap1 at the telomere to prevent chromosome end fusions
- Characterisation of the DNA binding domain of the yeast RAP1 protein.
- Characterisation of the DNA binding domain of the yeast RAP1 protein