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spRap1 and spRif1, recruited to telomeres by Taz1, are essential for telomere function in fission yeast

2001; Elsevier BV; Volume: 11; Issue: 20 Linguagem: Inglês

10.1016/s0960-9822(01)00503-6

1879-0445

Junko Kanoh, Fuyuki Ishikawa,

Genomics and Chromatin Dynamics

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Identification of human Rap1 implications for telomere evolution.Cell. 2000; 101: 471-483Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar]. Here, we describe two novel fission yeast proteins, spRap1 (S. pombe Rap1) and spRif1 (S. pombe Rif1), which are orthologous to scRap1 and scRif1, respectively. spRap1 and spRif1 are independently recruited to telomeres by interacting with Taz1. The rap1 mutant is severely defective in telomere length control, TPE, and telomere clustering toward the spindle pole body (SPB) at the premeiotic horsetail stage, indicating that spRap1 has critical roles in these telomere functions. The rif1 mutant also shows some defects in telomere length control and meiosis. Our results indicate that Taz1 provides binding sites for telomere regulators, spRap1 and spRif1, which perform the essential telomere functions. This study establishes the similarity of telomere organization in fission yeast and humans.