Linearly polarized excitation enhances signals from fluorescent voltage indicators |
| |
| Institution: | 1. Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts;2. Department of Physics, Harvard University, Cambridge, Massachusetts;3. Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts;4. Department of Imaging Physics, Delft University of Technology, Delft, the Netherlands;5. Department of Molecular Genetics, Erasmus University Medical Center, Rotterdam, the Netherlands |
| |
| Abstract: | Voltage imaging in cells requires high-speed recording of small fluorescent signals, often leading to low signal/noise ratios. Because voltage indicators are membrane bound, their orientations are partially constrained by the plane of the membrane. We explored whether tuning the linear polarization of excitation light could enhance voltage indicator fluorescence. We tested a panel of dye- and protein-based voltage indicators in mammalian cells. The dye BeRST1 showed a 73% increase in brightness between the least and most favorable polarizations. The protein-based reporter ASAP1 showed a 22% increase in brightness, and QuasAr3 showed a 14% increase in brightness. In very thin neurites expressing QuasAr3, improvements were anomalously large, with a 170% increase in brightness between polarization parallel versus perpendicular to the dendrite. Signal/noise ratios of optically recorded action potentials were increased by up to 50% in neurites expressing QuasAr3. These results demonstrate that polarization control can be a facile means to enhance signals from fluorescent voltage indicators, particularly in thin neurites or in high-background environments. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
