The eukaryotic DNA recombination repair protein BRCA2 is functional in the 
parasitic protozoan Trypanosoma brucei. The mechanism of the involvement of 
BRCA2 in homologous recombination includes its interaction with the DNA 
recombinase proteins of the RAD51 family. BRCA2 is known to interact with RAD51 
through its unique and essential BRC sequence motifs. T. brucei BRCA2 homolog 
(TbBRCA2) has fifteen repeating BRC motifs as compared to mammalian BRCA2 that 
has only eight. We report here our yeast 2-hybrid analysis studies on the 
interactions of TbBRCA2 BRC motifs with five different RAD51 paralogues of T. 
brucei. Our study revealed that a single BRC motif is sufficient to bind to 
these RAD51 paralogues. To test the possibility whether a single 44 amino acid 
long repeating unit of the TbBRCA2 BRC motif may be exploited as an inhibitor of 
T. brucei growth, we ectopically expressed this peptide segment in the procyclic 
form of the parasite and evaluated its effects on cell survival as well as the 
sensitivity of these cells to the DNA damaging agent methyl methane sulfonate 
(MMS). Expression of a single BRC motif led to MMS sensitivity and inhibited 
cellular proliferation in T. brucei.