BBSRC EASTBIO DTP - Piezo: a cardiac stretch-activated ion channel?

The heart senses and adapts to its own highly dynamic mechanical environment. This environment changes beat-by-beat, and over longer timescales due to physiological changes or as a consequence of disease. Failure to detect and adjust performance accordingly is associated with arrhythmias and sudden cardiac death. The molecular and cellular basis for this adaptation is not known, but mechanosensitive ion channels are hypothesized as key components. Preliminary data from our lab using the Drosophila heart model identify the stretch-activated Ca2+-permeable ion channel Piezo as being part of this adaptive response.

The aims of this project are to characterise the molecular and cellular basis of Piezo action in the adaptive response in the fly heart, and use the power of Drosophila genetics to identify further molecular components of the mechanism.

Using established assays you will study the physiological phenotypes associated with Piezo mutants in the fly heart. This will include the use of genetically-encoded Ca2+ sensors to measure and compare Ca2+ transients in the beating hearts of control and Piezo mutant flies. You will determine the subcellular focus of Piezo action using high-resolution confocal and electron microscopy. You will seek to identify the Piezo protein complex (i.e. channels such as TRP/ENaC and/or modulator subunits that tune Piezo activity/tether it to the cytoskeleton) using co-immunoprecipitation and mass-spectrometry approaches.

Together, this work will reveal whether Piezo is the elusive mechanosensitive ion channel required for the cardiac adaptive response, and extend our understanding of the mechanistic basis of Piezo activity by elucidating the molecular/cellular pathways of Piezo action. It is anticipated this work will have relevance beyond the fly, and a further goal will be to establish Piezo function in the mammalian heart and its relevance to human cardiac disease; this we will seek via collaboration with cardiac biologists/clinicians.

Research training:

Training in key practical skills/areas will include: (i) Microscopy (light, confocal and electron microscopy) and live imaging; (ii) Genomic tools and data-mining; (iii) Genetics, transgenics and genetic engineering technologies (e.g. CRISPR); (iv) Cell biology and immunocytochemistry; (v) Molecular biology; and (vi) Physiological techniques. Training is to be provided by myself (team leader) and other group members in association with the highly qualified managers of the state-of-the-art IMPACT imaging (Biomedical sciences) and Electron Microscopy facilities (School of Biological Sciences), and through interaction with established collaborators. Training will also be provided in (i) Science communication and dissemination skills; (ii) Publishing; and (iii) Other key transferable skills (such as research, time & project management; team working). Training is to be provided by myself and other group members in association with the excellent training opportunities offered within the School of Biomedical Sciences and within the University more widely (e.g. courses and events run by the Institute of Academic Development), and fostered through attendance/presentation at scientific meetings, and public engagement events (such as the Edinburgh Science Festival).