ST-1, a 39-kilodalton protein in Trypanosoma brucei, exhibits a dual affinity for the duplex form of the 29-base-pair subtelomeric repeat and its C-rich strand

Josiane E. Eid, Barbara Sollner-Webb

Research output: Contribution to journalArticle

Abstract

In our attempt to identify telomere region-binding proteins in Trypanosoma brucei, we identified ST-1, a polypeptide with novel features. ST-1 was chromatographically purified from S-100 cell extracts and was renatured from a sodium dodecyl sulfate-protein gel as a 39-kDa polypeptide. It forms a specific complex with the trypanosome telomere repeats of TTAGGG, but more significantly, it shows a higher affinity for the 29-bp subtelomere repeats of T. brucei, These 29-mer boxes are a large tandem series of telomere- derived repeats which separate the simple telomere DNA from middle-repetitive telomere-associated sequences on many chromosomes. ST-1 is the first example of a protein binding within such large repetitive subtelomere elements in trypanosomes or other organisms. ST-1 is also novel in that it has a selective affinity for the C-rich strands of both the subtelomeric 29-mer and the telomere repeats, comparable to that for the duplex form of the respective repeats. All previously described telomere-binding proteins have affinity for only the duplex form or for the G-rich strand. This C-rich strand binding specificity of ST-1 may provide insight into this protein's mechanism of binding in vivo.

Original languageEnglish (US)
Pages (from-to)389-397
Number of pages9
JournalMolecular and cellular biology
Volume15
Issue number1
DOIs
StatePublished - Jan 1995

ASJC Scopus subject areas

  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'ST-1, a 39-kilodalton protein in Trypanosoma brucei, exhibits a dual affinity for the duplex form of the 29-base-pair subtelomeric repeat and its C-rich strand'. Together they form a unique fingerprint.

  • Cite this