Optopatch: all-optical electrophysiology

Summary

Date: 
April 9, 2012 - 12:00pm - 1:00pm
Location: 
NW 243
About the Speaker
Name: 
Adam Cohen
Speaker Affiliation: 
Department of Chemistry and Chemical Biology

Microbial rhodopsin proteins enable optical control and optical readout of electrical activity in cells.  We developed genetic and optical tools to perform both tasks simultaneously.  We co-express a channelrhodopsin variant (for actuation) and an Archaerhodopsin variant (for readout) in the same cell.  Using a digital micromirror device, we stimulate the cell in an arbitrary spatiotemporal pattern, and then we record the ensuing activity with high-speed fluorescence microscopy.  Temporal interpolation techniques report the propagation of the action potential with 50 microsecond time resolution, and resolve spatially dependent effects of ion channel modulators.  I will discuss applications to human iPS-derived cardiomyocytes and neurons, as well as ongoing efforts to image neural activity in vivo.