The F-box Protein CFB2 Is Required for Cytokinesis of Bloodstream-Form Trypanosoma Brucei

Mol Biochem Parasitol. 2007 Dec;156(2):217-24. doi: 10.1016/j.molbiopara.2007.08.005. Epub 2007 Aug 21.


F-box proteins serve as mediators in targeting bound target proteins for ubiquitination and destruction. We here describe the roles of two F-box proteins, CFB1 and CFB2, in the trypanosome cell cycle. Five almost identical copies of CFB1 are arranged in a direct tandem repeat on Trypanosoma brucei chromosome 1; immediately downstream is a single CFB2 gene. RNAi targeting CFB1 in bloodstream-form trypanosomes had a transient effect on growth and mitosis. Depletion of CFB2, in contrast, resulted in immediate growth arrest and rapid cell death. CFB2-depleted cells accumulated nuclei and kinetoplasts with the corresponding numbers of basal bodies and flagella. The CFB2 transcript was less abundant in procyclic-form trypanosomes, and RNAi against CFB2 in these forms had no effect on growth. These results suggest that CFB2 is required for bloodstream-form trypanosome cytokinesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Death
  • Cytokinesis / genetics
  • Cytokinesis / physiology*
  • F-Box Proteins / genetics
  • F-Box Proteins / physiology*
  • Gene Dosage
  • Gene Silencing
  • Protozoan Proteins / genetics
  • Protozoan Proteins / physiology*
  • RNA Interference
  • Trypanosoma brucei brucei / genetics
  • Trypanosoma brucei brucei / physiology*


  • F-Box Proteins
  • Protozoan Proteins