The regulation of procyclin expression in Trypanosoma bruceli: making or breaking the rules?

The identification of procyclins as stage-specific coat proteins of procyclic forms of Trypanosoma brucei has not only provided a convenient molecular marker for the differentiation of bloodstream-form trypanosomes into procyclic forms, but has also allowed some important insights into gene regulation in trypanosomes. Here, Adrian Hehl and Isabel Roditi summarize what has been learnt in the past few years about the control mechanisms that may contribute to the stage-specific expression of procyclins.