Majeed Bakari-Soale

1 Introduction The African trypanosome Trypanosoma brucei is a unicellular protist parasite of medical and veterinary importance. The parasite is strictly extracellular and is transmitted between its mammalian hosts by an insect vector, the tsetse fly. In the mammalian host, T. brucei thrives in the blood and tissue fluids despite being exposed to the host's immune system. Infection by the parasite can become chronic, lasting for months or years.

Abstract The variant surface glycoprotein (VSG) of African trypanosomes is essential for survival of bloodstream form parasites. These parasites undergo antigenic variation, an immune evasion strategy in which they periodically switch VSG expression from one isoform to another. The molecular processes central to the expression and regulation of the VSG are however not fully understood. In general, the regulation of gene expression in trypanosomes is largely post-transcriptional.