Refining super-resolution microscopy: lessons learnt from imaging intracellular signalling nanodomains

Speaker: Dr. Izzy Jayasinghe, Lecturer in Cardiovascular Sciences and UKRI Future Leader Fellow, University of Leeds

Abstract:

This talk will outline a decade of research in Cell Biology and Biophysics which has utilised super-resolution microscopy – a family of optical imaging techniques which strive to resolve structures which were previously limited to electron microscopy exclusively. Intracellular signalling ‘nanodomains’ are some of the most commonly imaged structures over the last few decades. In muscle cells which make up the tissue of the heart, these nanodomains orchestrate a series of calcium signals which underpin the heartbeat. 

In this seminar, I will outline how the adaptation of chemical photo-switching of aromatic fluorescent labels, together with the first generation of super-resolution microscopy modalities (e.g. dSTORM) enabled us to acquire the first optically-resolved images of nanodomains, a decade ago. 

Over the last few years, there has been a wave of newer super-resolution microscopy modalities which have transformed the way we visualise nanodomains. By refining and re-developing these methods, we have been able to map, count and distinguish individual ion channels and regulatory proteins, which make up the nanodomains in the heart. We can also visually identify distinct chemical signatures of individual ion channels in situ, perform spatial statistics on their interactions during the genesis of calcium signals and simulate these calcium signals in silico, at an unprecedented level of spatial and temporal detail. I will detail the adaptations and refinements of DNA-PAINT and “Enhanced Expansion Microscopy” which have enabled these observations. 

Finally, I will also introduce ‘sandSTORM’ a brand new method which has been developed in my team, exploiting the spontaneous photoluminescence properties of nanodiamonds, as one of the fastest super-resolution microscopy modalities.