RPA-like proteins mediate yeast telomere function.
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.
Gao
Hua
H
The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA.
Cervantes
Rachel B
RB
Mandell
Edward K
EK
Otero
Joel H
JH
Lundblad
Victoria
V
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*
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