title: Telomerase is required to protect chromosomes with vertebrate-type T2AG3 3' ends in Saccharomyces cerevisiae.
abstract: Telomeres containing vertebrate-type DNA repeats can be stably maintained in Saccharomyces cerevisiae cells. We show here that telomerase is required for growth of yeast cells containing these vertebrate-type telomeres. When present at the chromosome termini, these heterologous repeats elicit a DNA damage response and a certain deprotection of telomeres. The data also show that these phenotypes are due only to the terminal localization of the vertebrate repeats because if they are sandwiched between native yeast repeats, no phenotype is observed. Indeed and quite surprisingly, in this latter situation, telomeres are of virtually normal lengths, despite the presence of up to 50% of heterologous repeats. Furthermore, the presence of the distal vertebrate-type repeats can cause increased problems of the replication fork. These results show that in budding yeast the integrity of the 3' overhang is required for proper termination of telomere replication as well as protection.
authors.affiliation: Département de Microbiologie et d'Infectiologie, Groupe ARN/RNA Group, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, 3001 12e Ave. Nord, Sherbrooke, Quebec J1H 5N4, Canada.
authors.forename: Amadou
authors.initials: A
authors.lastname: Bah
authors.forename: Eric
authors.initials: E
authors.lastname: Gilson
authors.forename: Raymund J
authors.initials: RJ
authors.lastname: Wellinger
mesh_terms: D001483:Base Sequence; D002453:Cell Cycle; D015825:Chromosomes, Fungal; D004249:DNA Damage; D017931:DNA Primers; D004260:DNA Repair; D005434:Flow Cytometry; D016133:Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics*; D019098:Telomerase / Q000378:metabolism*; D016615:Telomere
chemical_list: D017931:DNA Primers; D019098:Telomerase