Structure, function, and replication of Saccharomyces cerevisiae telomeres.

A combination of classical genetic, biochemical, and molecular biological approaches have generated a rather detailed understanding of the structure and function of Saccharomyces telomeres. Yeast telomeres are essential to allow the cell to distinguish intact from broken chromosomes, to protect the end of the chromosome from degradation, and to facilitate the replication of the very end of the chromosome. In addition, yeast telomeres are a specialized site for gene expression in that the transcription of genes placed near them is reversibly repressed. A surprisingly large number of genes have been identified that influence either telomere structure or telomere function (or both), although in many cases the mechanism of action of these genes is poorly understood. This article reviews the recent literature on telomere biology and highlights areas for future research.