Novel Imaging Techniques in Cardiac Ion Channel Research
Light microscopy has long been at the forefront of biological research, perhaps most significantly in the form of fluorescence microscopy. This technique, paired with the ongoing discovery and synthesis of increasingly brilliant fluorophores, allows for visualization of the internal machinations of cells with molecular specificity. However, until recently, a persistent limitation of fluorescence microscopy—the diffraction of visible light—has restricted elucidation of the subcellular organization and localization of molecules to spatial resolutions of 200–300 nanometers. The invention and implementation of several super-resolution fluorescence microscopies (SRFMs) over the last 10 years have circumvented this diffraction limit and allowed up to tenfold improvements in resolution. Applications of SRFM in cardiology research have already illuminated aspects of the cardiac nanoscale architecture which were previously unobservable, opening the door for new avenues of research. These discoveries include the sub-diffraction structure of the intercalated disk, the t-tubular network, and excitation-contraction coupling. In this chapter we will review SRFM methodologies, present some examples of their successful application in cardiac research, and discuss the techniques’ advantages, ongoing challenges, and future potential.
KeywordsSuper-resolution microscopy PALM STORM STED Single-molecule localization microscopy
The authors acknowledge the help and critical discussions with members of the Rothenberg and Delmar labs.
Compliance with Ethical Standards
Sources of Funding
Work in the Rothenberg lab is funded by the NIH grants R01-GM057691 and R21-CA187612 and the American Cancer Society grant (ACS 130304-RSG-16-241-01-DMC). Research in the Delmar lab is supported by NIH grants RO1-GM57691, RO1-HL134328, and RO1-HL136179.
Conflict of Interest
Authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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