title: RPA-like proteins mediate yeast telomere function.
abstract: Cdc13, Stn1 and Ten1 are essential yeast proteins that both protect chromosome termini from unregulated resection and regulate telomere length. Cdc13, which localizes to telomeres through high-affinity binding to telomeric single-stranded DNA, has been extensively characterized, whereas the contribution(s) of the Cdc13-associated Stn1 and Ten1 proteins to telomere function have remained unclear. We show here that Stn1 and Ten1 are DNA-binding proteins with specificity for telomeric DNA substrates. Furthermore, Stn1 and Ten1 show similarities to Rpa2 and Rpa3, subunits of the heterotrimeric replication protein A (RPA) complex, which is the major single-stranded DNA-binding activity in eukaryotic cells. We propose that Cdc13, Stn1 and Ten1 function as a telomere-specific RPA-like complex. Identification of an RPA-like complex that is targeted to a specific region of the genome suggests that multiple RPA-like complexes have evolved, each making individual contributions to genomic stability.
authors.affiliation: The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Gao
authors.forename: Rachel B
authors.initials: RB
authors.lastname: Cervantes
authors.forename: Edward K
authors.initials: EK
authors.lastname: Mandell
authors.forename: Joel H
authors.initials: JH
authors.lastname: Otero
authors.forename: Victoria
authors.initials: V
authors.lastname: Lundblad
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000737:chemistry / Q000378:metabolism*; D004271:DNA, Fungal / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D051716:Replication Protein A / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D013379:Substrate Specificity; D016615:Telomere / Q000378:metabolism*; D034501:Telomere-Binding Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004271:DNA, Fungal; D051716:Replication Protein A; D029701:Saccharomyces cerevisiae Proteins; C428109:Stn1 protein, S cerevisiae; C512860:TEN1 protein, S cerevisiae; D034501:Telomere-Binding Proteins