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TEBP-1 and TEBP-2 are double-stranded telomere binders required for fertility

ABSTRACT: Telomeres are the ends of linear chromosomes and consist of repetitive double- and single-stranded DNA sequences. Telomeres are bound by dedicated protein complexes, such as shelterin in mammals. In the nematode Caenorhabditis elegans, a comprehensive understanding of the proteins interacting with the telomere sequence is lacking. Here, we harnessed a quantitative proteomics approach to screen for proteins binding to C. elegans telomeres, and identified TEBP-1 and TEBP-2, two paralogs that associate to telomeres in vitro and in vivo. TEBP-1 and TEBP-2 form a telomeric complex with the known single-stranded telomere-binding proteins POT-1, POT-2, and MRT-1. tebp-1 and tebp-2 mutants display strikingly distinct phenotypes: tebp-1 mutants have longer telomeres than wild-type animals, while tebp 2 mutants display shorter telomeres and a mortal germline, a phenotype characterized by transgenerational germline deterioration. Notably, tebp 1;tebp-2 double mutant animals are synthetic sterile, with germlines showing signs of severe mitotic and meiotic arrest. These results define the first telomere-binding complex of C. elegans, including TEBP-1 and TEBP-2, two double-stranded telomere binders required for fertility.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Caenorhabditis Elegans

SUBMITTER: F Butter

LAB HEAD: Falk Butter

PROVIDER: PXD019241 | Pride | 2021-03-09

REPOSITORIES: Pride

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			Action	DRS
	20150110_QEP2_FBU_SD_telomere_Cel_C1_1.raw	Raw
	20150110_QEP2_FBU_SD_telomere_Cel_C1_2.raw	Raw
	20150110_QEP2_FBU_SD_telomere_Cel_C1_3.raw	Raw
	20150110_QEP2_FBU_SD_telomere_Cel_C1_4.raw	Raw
	20150110_QEP2_FBU_SD_telomere_Cel_C2_1.raw	Raw

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