Single-Cell Biophysics: Measurement, Modulation, and Modeling

Single-Cell Biophysics: Measurement, Modulation, and Modeling

Poster Abstracts

81-POS Board 41 Imaging Membrane Potential of the Endoplasmic Reticulum with a Genetically-Encoded Voltage Indicator Masoud Sepehri rad 1 , Lawrence B. Cohen 1,2 .Bradley J. Baker 1 , 1 Korea Institute of Science and Technology, seoul, South Korea, 2 Yale University School of Medicine,, New Haven, CT, USA. In eukaryotic cells, the endoplasmic reticulum (ER) is the largest continuous membrane-enclosed network which surrounds a single lumen. Using a newly designed genetically encoded voltage indicator (GEVI), we applied the patch clamp technique to HEK293 cells and found that there is an electrical interaction between plasma membrane and ER membrane. We have optically monitored the voltage changes in both of these membranes simultaneously. The optical signal of the GEVI in the plasma membrane is consistent from trial to trial. However, the ER signal decreases in size with repeated trials while the plasma membrane resistance remains constant. This dynamic behavior of the internal signal suggests that voltage may stress the ER causing it to remodel and change its resistance. Our findings further suggest that the ER may transfer electrical signals from the plasma membrane to the nuclear envelope.

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