Protean permeases: Diverse roles for membrane transport proteins in kinetoplastid protozoa

Abstract Kinetoplastid parasites such as Trypanosoma brucei , Trypanosoma cruzi , and Leishmania species rely upon their insect and vertebrate hosts to provide a plethora of nutrients throughout their life cycles. Nutrients and ions critical for parasite survival are taken up across the parasite plasma membrane by transporters and channels, polytopic membrane proteins that provide substrate-specific pores across the hydrophobic barrier. However, transporters and channels serve a wide range of biological functions beyond uptake of nutrients. This article highlights the diversity of activities that these integral membrane proteins serve and underscores the emerging complexity of their functions.