Cdc13 is predominant over Stn1 and Ten1 in preventing chromosome end fusions

eLife

Jia-Cheng Liu¹  Yangyang Shao¹  Xin Gu¹  Chen Cai¹  Xiaoli Xue¹  Jin-Qiu Zhou¹  Zhongjun Qin²  Ting-Yi Li²  Ming-Hong He²  Ning Lu²  Zhi-Jing Wu²  Xin Man² 

[1] University of Chinese Academy of Sciences, Shanghai, China;The State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences;

关键词: single chromosome yeast;    CST complex;    chromosome end fusion;    telomere protection;    homologous recombination;   

DOI  :  10.7554/eLife.53144

来源: DOAJ

【 摘 要 】

Telomeres define the natural ends of eukaryotic chromosomes and are crucial for chromosomal stability. The budding yeast Cdc13, Stn1 and Ten1 proteins form a heterotrimeric complex, and the inactivation of any of its subunits leads to a uniformly lethal phenotype due to telomere deprotection. Although Cdc13, Stn1 and Ten1 seem to belong to an epistasis group, it remains unclear whether they function differently in telomere protection. Here, we employed the single-linear-chromosome yeast SY14, and surprisingly found that the deletion of CDC13 leads to telomere erosion and intrachromosome end-to-end fusion, which depends on Rad52 but not Yku. Interestingly, the emergence frequency of survivors in the SY14 cdc13Δ mutant was ~29 fold higher than that in either the stn1Δ or ten1Δ mutant, demonstrating a predominant role of Cdc13 in inhibiting telomere fusion. Chromosomal fusion readily occurred in the telomerase-null SY14 strain, further verifying the default role of intact telomeres in inhibiting chromosome fusion.

【 授权许可】

Unknown