Development of zebrafish models to track extracellular vesicle trafficking in response to cardiac injury

MSc by Research position is available for one year supervised by Prof Paul Martin, Dr Rebecca Richardson and Professor Costanza Emanueli.
This is an exciting opportunity for a talented and motivated student to work on a project combining state-of-the-art imaging techniques and directly clinically relevant cardiovascular studies in an in vivo zebrafish model system. Extracellular vesicles (EVs), including exosomes and microparticles, are released from the plasma membrane of cells and used as a form of intercellular communication via packaged vesicular contents consisting of nucleic acids (especially microRNAs), proteins and lipids (1,2). EVs can be taken up by recipient cells and instructed to respond or change behaviour. For example, Professor Emanueli’s lab has shown that during diabetes, endothelial cells use microparticles to deliver microRNA-503 to pericytes, affecting their function (3). Because they protect their molecular cargo from degradation, EVs can induce short and long-range functional responses. However, our current knowledge of endogenous EV trafficking remains limited and existing technologies do not allow identification of the cellular origin of circulating EVs or to track the circulation and incorporation of EVs by cardiac cells. This project will develop and employ novel genetic zebrafish models enabling visualisation of exosome trafficking to and from the heart in vivo.

The supervisors are expert in zebrafish processes of cardiovascular development and regeneration. Moreover, the co-supervisor has developed methods to detect and characterise EVs from culture media and blood and to study the EV microRNA cargo transfer to recipient cells. Initially, the successful student will culture cardiomyocytes from adult zebrafish (4) to characterise release and uptake of endogenous EVs and how they respond to exogenous EVs containing “therapeutic” microRNAs in vitro. Subsequently, the student will use transgenic zebrafish, specifically expressing membrane tethered GFP in cardiomyocytes (and their EVs), to characterise endogenous zebrafish EVs from blood under homeostatic conditions and at different time-points post cryoinjury induced cardiac damage, via established techniques. Recent reports have shown that targeting GFP to the plasma membrane of target cells in this way can be used to visualise EVs in vivo (5). The student will then take advantage of expertise of the main supervisor and new techniques (6) to perform in vivo imaging of the live heart of Tg(myl7:EGFP-Hsa.HRAS) zebrafish to observe formation and uptake of endogenous, GFP-labelled EVs. This project represents an exciting opportunity to develop a new aspect of zebrafish biology whilst simultaneously contributing to a highly translational and clinically applicable project supported by world-class research groups in both fields.

Website: http://www.bristol.ac.uk/phys-pharm/people/beck-j-richardson/overview.html