Recent advances in transfection technology have been exploited to addr
ess fundamental questions relating to secretory trafficking in African
trypanosomes. Targeted gene disruptions and ectopic expression of the
major stage-specific surface proteins have provided unexpected insigh
ts into both the function and assembly of the essential parasite surfa
ce coats. A growing list of novel secretory cargo molecules, as well a
s advances in the characterization of trypanosoma[ secretory machinery
, provide a unique model system for the study of eukaryotic secretory
processes.