Identification and characterization of three telomere repeat-binding factors in rice

Biochem Biophys Res Commun. 2008 Jul 18;372(1):85-90. doi: 10.1016/j.bbrc.2008.04.181. Epub 2008 May 12.

Abstract

Telomeres consist of nucleoprotein complexes that protect chromosome end structures. Here, we describe three OsTRBF genes, encoding telomere repeat-binding factors of the single Myb histone family in rice. The predicted proteins contain a Myb DNA-binding motif and a linker histone H1/H5 domain in the N-terminal and central regions, respectively. The OsTRBF transcripts were constitutively detected in rice plants grown under greenhouse conditions. Gel retardation assays showed that these OsTRBF proteins bind specifically to the plant double-stranded telomeric sequence, TTTAGGG, with markedly different binding affinities as judged by their respective dissociation constants. Yeast two-hybrid and in vitro pull-down assays indicated that both OsTRBF1 and OsTRBF2 interact with one another to form homo- and hetero-complexes, while OsTRBF3 appeared to act as a monomer. Our results suggest that OsTRBFs play combinatory roles in the function and structure of telomeres in rice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Dimerization
  • Electrophoretic Mobility Shift Assay
  • Molecular Sequence Data
  • Oryza / genetics
  • Oryza / metabolism*
  • Plant Proteins / chemistry
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Protein Structure, Tertiary
  • Telomere / metabolism*
  • Telomere-Binding Proteins / chemistry
  • Telomere-Binding Proteins / genetics
  • Telomere-Binding Proteins / metabolism*
  • Two-Hybrid System Techniques

Substances

  • Plant Proteins
  • Telomere-Binding Proteins