Rap1p and telomere length regulation in yeast.

摘要: Telomere length in the yeast Saccharomyces cerevisiae is under stringent genetic control such that a narrow distribution of TG1-3 repeats observed. Previous studies have shown Rap1p, which binds to double-stranded telomeric repeats, plays role regulating repeat length: point mutations Rap1p C-terminus often result higher average telomere and deletion this region causes extreme elongation. We investigated further process. Our results suggest regulated by negative feedback mechanism can sense number molecules bound at chromosome end. This regulatory requires two other proteins, Rif1p Rif2p, interact with each C-terminus. Although same C-terminal domain also involved initiation position effect (telomeric transcriptional silencing), function appears be separate from, indeed antagonistic to, its regulation.