Resolution of telomere associations by TRF1 cleavage in mouse embryonic stem cells

Mol Biol Cell. 2014 Jul 1;25(13):1958-68. doi: 10.1091/mbc.E13-10-0564. Epub 2014 May 14.


Telomere associations have been observed during key cellular processes such as mitosis, meiosis, and carcinogenesis and must be resolved before cell division to prevent genome instability. Here we establish that telomeric repeat-binding factor 1 (TRF1), a core component of the telomere protein complex, is a mediator of telomere associations in mammalian cells. Using live-cell imaging, we show that expression of TRF1 or yellow fluorescent protein (YFP)-TRF1 fusion protein above endogenous levels prevents proper telomere resolution during mitosis. TRF1 overexpression results in telomere anaphase bridges and aggregates containing TRF1 protein and telomeric DNA. Site-specific protein cleavage of YFP-TRF1 by tobacco etch virus protease resolves telomere aggregates, indicating that telomere associations are mediated by TRF1. This study provides novel insight into the formation and resolution of telomere associations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / metabolism
  • Cell Cycle
  • Cell Survival
  • Embryonic Stem Cells / metabolism
  • Embryonic Stem Cells / ultrastructure*
  • Endopeptidases / biosynthesis
  • Luminescent Proteins / metabolism
  • Mice, 129 Strain
  • Mitosis
  • Proteolysis
  • Recombinant Fusion Proteins / metabolism
  • Telomere / metabolism*
  • Telomere / ultrastructure
  • Telomeric Repeat Binding Protein 1 / metabolism*


  • Bacterial Proteins
  • Luminescent Proteins
  • Recombinant Fusion Proteins
  • Telomeric Repeat Binding Protein 1
  • yellow fluorescent protein, Bacteria
  • Endopeptidases
  • TEV protease