The double-stranded DNA-binding proteins TEBP-1 and TEBP-2 form a telomeric complex with POT-1

Nat Commun. 2021 May 11;12(1):2668. doi: 10.1038/s41467-021-22861-2.

Abstract

Telomeres are bound by dedicated proteins, which protect them from DNA damage and regulate telomere length homeostasis. 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 identify TEBP-1 and TEBP-2, two paralogs expressed in the germline and embryogenesis that associate to telomeres in vitro and in vivo. 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. Notably, tebp-1;tebp-2 double mutant animals have synthetic sterility, with germlines showing signs of severe mitotic and meiotic arrest. Furthermore, we show that POT-1 forms a telomeric complex with TEBP-1 and TEBP-2, which bridges TEBP-1/-2 with POT-2/MRT-1. These results provide insights into the composition and organization of a telomeric protein complex in C. elegans.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Base Sequence
  • Binding Sites / genetics
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / classification
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • DNA / genetics
  • DNA / metabolism*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Germ Cells / metabolism
  • Microscopy, Fluorescence / methods
  • Multiprotein Complexes / genetics
  • Multiprotein Complexes / metabolism*
  • Mutation
  • Phylogeny
  • Protein Binding
  • Protein Isoforms / classification
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Telomere / genetics
  • Telomere / metabolism*
  • Telomere-Binding Proteins / classification
  • Telomere-Binding Proteins / genetics
  • Telomere-Binding Proteins / metabolism*

Substances

  • Caenorhabditis elegans Proteins
  • DNA-Binding Proteins
  • Multiprotein Complexes
  • POT-1 protein, C elegans
  • Protein Isoforms
  • Telomere-Binding Proteins
  • tebp-1 protein, C elegans
  • tebp-2 protein, C elegans
  • DNA