Yeast Ku as a regulator of chromosomal DNA end structure.
During telomere replication in yeast, chromosome ends acquire an S-phase-specific overhang of the guanosine-rich strand. Here it is shown that in cells lacking Ku, a heterodimeric protein involved in nonhomologous DNA end joining, these overhangs are present throughout the cell cycle. In vivo cross-linking experiments demonstrated that Ku is bound to telomeric DNA. These results show that Ku plays a direct role in establishing a normal DNA end structure on yeast chromosomes, conceivably by functioning as a terminus-binding factor. Because Ku-mediated DNA end joining involving telomeres would result in chromosome instability, our data also suggest that Ku has a distinct function when bound to telomeres.
Pubmed ID: 9563951 RIS Download
Antigens, Nuclear | Binding Sites | Chromosomes, Fungal | DNA Helicases | DNA, Fungal | DNA-Binding Proteins | Fungal Proteins | G2 Phase | Genes, Fungal | Ku Autoantigen | Mitosis | Mutation | Nuclear Proteins | S Phase | Saccharomyces cerevisiae | Saccharomyces cerevisiae Proteins | Telomerase | Telomere | Temperature | Transformation, Genetic