Clive Wilson - Development & Cell Biology - 'Dissecting the conserved in vivo regulation of Rab11-exosomes in Drosophila'

Exosomes are nano-sized vesicles secreted from the endosomal compartments of cells. They carry a multitude of different bioactive cargos, including proteins, RNAs and lipids that can reprogramme target cells. Exosomes have been implicated in many pathologies, in particular cancer, where they can prime pre-metastatic sites, induce drug resistance and suppress the immune system. However, they are also involved in complex physiological cell-cell signalling events. For example, we found that exosomes produced in the male accessory gland of the fruit fly reprogramme female behaviour, so she rejects other males that try to mate with her. Using this fly model in which exosomes are made inside unusually large intracellular compartments that can be imaged in real-time, we identified a novel evolutionarily conserved exosome subtype, called Rab11-exosomes, which is the primary mediator of key physiological and cancer-relevant exosome functions, despite representing a small fraction of all secreted vesicles. We recently identified multiple new conserved regulators of Rab11-exosomes by combining human Rab11-exosome proteomics with fly genetic analysis. This project will involve analysing these regulators further, focusing on how they shape Rab11-exosomes, coat them with extravesicular proteins and traffic them to the cell surface, mechanisms that are all potential targets for future exosome subtype-specific therapies.