We identified and characterized a protein (STB-1) from the nuclear extract of Caenorhabditis elegans that specifically binds single-stranded telomere DNA sequences, but not the corresponding RNA sequences. STB-1 binding activity is specific to the nematode telomere, but not to the human or plant telomere. STB-1 requires the core nucleotides of GCTTAGG and three spacer nucleotides in front of them for binding. While any single nucleotide change in the core sequence abolishes binding, the spacer nucleotides tolerate substitution. STB-1 was determined to be a basic protein of 45 kDa by Southwestern analyses. STB-1 forms a stable complex with DNA once bound to the telomere.
Bibliographical noteFunding Information:
We thank M.S. Choi and lab members for critical reading and advice. This work was supported by Korea Research Foundation Grant KRF-2000-2-0821 to I.K.C. and J.H.L.
All Science Journal Classification (ASJC) codes
- Structural Biology
- Molecular Biology
- Cell Biology