Roles of heterochromatin and telomere proteins in regulation of fission yeast telomere recombination and telomerase recruitment.
Volume
285
Pagination
5327 - 5337
DOI
10.1074/jbc.M109.078840
Journal
J Biol Chem
Issue
Metadata
Show full item recordAbstract
When the telomerase catalytic subunit (Trt1/TERT) is deleted, a majority of fission yeast cells survives by circularizing chromosomes. Alternatively, a small minority survives by maintaining telomeric repeats through recombination among telomeres. The recombination-based telomere maintenance in trt1Delta cells is inhibited by the telomere protein Taz1. In addition, catalytically inactive full-length Trt1 (Trt1-CI) and truncated Trt1 lacking the T-motif and reverse transcriptase (RT) domain (Trt1-DeltaT/RT) can strongly inhibit recombination-based survival. Here, we investigated the effects of deleting the heterochromatin proteins Swi6 (HP1 ortholog) and Clr4 (Suv39 family of histone methyltransferases) and the telomere capping complex subunits Poz1 and Ccq1 on Taz1- and Trt1-dependent telomere recombination inhibition. The ability of Taz1 to inhibit telomere recombination did not require Swi6, Clr4, Poz1, or Ccq1. Although Swi6, Clr4, and Poz1 were dispensable for the inhibition of telomere recombination by Trt1-CI, Ccq1 was required for efficient telomere recruitment of Trt1 and Trt1-CI-dependent inhibition of telomere recombination. We also found that Swi6, Clr4, Ccq1, the checkpoint kinase Rad3 (ATR ortholog), and the telomerase regulatory subunit Est1 are all required for Trt1-DeltaT/RT to inhibit telomere recombination. However, because loss of Swi6, Clr4, Rad3, Ccq1, or Est1 did not significantly alter the recruitment efficiency of Trt1-DeltaT/RT to telomeres, these factors are likely to enhance the ability of Trt1-DeltaT/RT to inhibit recombination-based survival by contributing to the negative regulation of telomere recombination.
Authors
Khair, L; Subramanian, L; Moser, BA; Nakamura, TMCollections
Language
Copyright statements
Related items
Showing items related by title, author, creator and subject.
-
Direct binding of CEP85 to STIL ensures robust PLK4 activation and efficient centriole assembly.
Liu, Y; Gupta, GD; Barnabas, DD; Agircan, FG; Mehmood, S; Wu, D; Coyaud, E; Johnson, CM; McLaughlin, SH; Andreeva, A (2018-04-30)Centrosomes are required for faithful chromosome segregation during mitosis. They are composed of a centriole pair that recruits and organizes the microtubule-nucleating pericentriolar material. Centriole duplication is ... -
A kinase-independent role for the Rad3(ATR)-Rad26(ATRIP) complex in recruitment of Tel1(ATM) to telomeres in fission yeast.
Subramanian, L; Nakamura, TM (2010-02-05)ATM and ATR are two redundant checkpoint kinases essential for the stable maintenance of telomeres in eukaryotes. Previous studies have established that MRN (Mre11-Rad50-Nbs1) and ATRIP (ATR Interacting Protein) interact ... -
Roles of the checkpoint sensor clamp Rad9-Rad1-Hus1 (911)-complex and the clamp loaders Rad17-RFC and Ctf18-RFC in Schizosaccharomyces pombe telomere maintenance.
Khair, L; Chang, Y-T; Subramanian, L; Russell, P; Nakamura, TM (2010-06-01)While telomeres must provide mechanisms to prevent DNA repair and DNA damage checkpoint factors from fusing chromosome ends and causing permanent cell cycle arrest, these factors associate with functional telomeres and ...