Sua5p a single-stranded telomeric DNA-binding protein facilitates telomere replication.
In budding yeast Saccharomyces cerevisiae, telomere length maintenance involves a complicated network as more than 280 telomere maintenance genes have been identified in the nonessential gene deletion mutant set. As a supplement, we identified additional 29 telomere maintenance genes, which were previously taken as essential genes. In this study, we report a novel function of Sua5p in telomere replication. Epistasis analysis and telomere sequencing show that sua5Delta cells display progressively shortened telomeres at early passages, and Sua5 functions downstream telomerase recruitment. Further, biochemical, structural and genetic studies show that Sua5p specifically binds single-stranded telomeric (ssTG) DNA in vitro through a distinct DNA-binding region on its surface, and the DNA-binding ability is essential for its telomere function. Thus, Sua5p represents a novel ssTG DNA-binding protein and positively regulates the telomere length in vivo.
Meng
Fei-Long
FL
The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, China.
Hu
Yan
Y
Shen
Ning
N
Tong
Xia-Jing
XJ
Wang
Jianyong
J
Ding
Jianping
J
Zhou
Jin-Qiu
JQ
D004261:DNA Replication; D004271:DNA, Fungal / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D016615:Telomere / Q000378:metabolism*
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; C541142:SUA5 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins