Cleveland Clinic Lerner College of MedicineUnited States of America
Telomeres are specialized structures essential for genomic stability in eukaryotic cells. Inducible systems causing telomere shortening or telomere formation from short tracts of telomere repeats were developed in the late 1990s in Saccharomyces cerevisiae and have been adapted to investigate multiple aspects of telomere biology. In the formation system, an internal tract of telomere repeats is placed next to an inducible double-strand break. Inducing the break converts the telomere tract into a functional telomere whose fate can be followed kinetically and allows one to assay elongation, protein recruitment, and the DNA damage checkpoint activation. This work was extended to Schizosaccharomyces pombe, as it shares some features of telomeric chromatin with mammalian cells that are missing in S. cerevisiae. The S. pombe system has revealed novel aspects of telomeric chromatin formation and similarities with S. cerevisiae. This chapter will review these past discoveries in different yeast model organisms, and what they reveal about telomere physiology that may well be conserved in mammals.
Part of the book: Telomerase and non-Telomerase Mechanisms of Telomere Maintenance