DEVELOPMENTAL REGULATION OF NUCLEAR GENE-EXPRESSION IN TRYPANOSOMA-BRUCEI

The kinetoplastids branched very early in eukaryotic evolution and exhibit several remarkable aspects of biochemistry and molecular biology. In addition to increasing the appreciation of the range of options available in eukaryotic biochemistry, each discovery of a difference between trypanosomes and their hosts gives hope for the development of new types of drugs. African trypanosomes grow in two rather different environments: the mammalian extracellular fluids and the alimentary system of the tsetse fly. Survival in the mammal depends on an ability to evade the host immune response; the different conditions in the fly necessitate numerous metabolic adapations. This chapter summarizes the available knowledge on the development regulation of nuclear gene expression in T. brucei brucei, a close relative of T. b. rhodesiense, which is a favorite model organism because it infects cattle and other animals but not humans. The chapter particularly emphasizes the transcription of the genes encoding the major surface proteins. Some important examples from other kinetoplastids, particularly Leishmania species, are also mentioned in the chapter. © 1992, ACADEMIC PRESS, INC.