title: Dependence of the regulation of telomere length on the type of subtelomeric repeat in the yeast Saccharomyces cerevisiae.
abstract: In the yeast Saccharomyces cerevisiae, chromosomes terminate with approximately 400 bp of a simple repeat poly(TG(1-3)). Based on the arrangement of subtelomeric X and Y' repeats, two types of yeast telomeres exist, those with both X and Y' (Y' telomeres) and those with only X (X telomeres). Mutations that result in abnormally short or abnormally long poly(TG(1-3)) tracts have been previously identified. In this study, we investigated telomere length in strains with two classes of mutations, one that resulted in short poly(TG(1-3)) tracts (tel1) and one that resulted in elongated tracts (pif1, rap1-17, rif1, or rif2). In the tel1 pif1 strain, Y' telomeres had about the same length as those in tel1 strains and X telomeres had lengths intermediate between those in tel1 and pif1 strains. Strains with either the tel1 rap1-17 or tel1 rif2 genotypes had short tracts for all chromosome ends examined, demonstrating that the telomere elongation characteristic of rap1-17 and rif2 strains is Tel1p-dependent. In strains of the tel1 rif1 or tel1 rif1 rif2 genotypes, telomeres with Y' repeats had short terminal tracts, whereas most of the X telomeres had long terminal tracts. These results demonstrate that the regulation of telomere length is different for X and Y' telomeres.
authors.affiliation: Department of Biology, Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina 27599-3280, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Craven
authors.forename: T D
authors.initials: TD
authors.lastname: Petes
mesh_terms: D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology; D015825:Chromosomes, Fungal / Q000648:ultrastructure*; D004265:DNA Helicases / Q000235:genetics / Q000502:physiology; D004271:DNA, Fungal / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology; D004843:Epistasis, Genetic; D005656:Fungal Proteins / Q000235:genetics / Q000502:physiology*; D047908:Intracellular Signaling Peptides and Proteins; D017346:Protein Serine-Threonine Kinases; D012091:Repetitive Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000648:ultrastructure*; D029701:Saccharomyces cerevisiae Proteins; D016615:Telomere / Q000648:ultrastructure*; D034501:Telomere-Binding Proteins
chemical_list: D002352:Carrier Proteins; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D047908:Intracellular Signaling Peptides and Proteins; C105362:RIF2 protein, S cerevisiae; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D034501:Telomere-Binding Proteins; C074461:RIF1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; C513623:TEL1 protein, S cerevisiae; C085463:PIF1 protein, S cerevisiae; D004265:DNA Helicases