Extended Data Fig. 2: Mapping neuronal excitability in Cre-on Optopatch3 transgenic mice (line Ai155).
From: Voltage imaging and optogenetics reveal behaviour-dependent changes in hippocampal dynamics
a, Construct design for a Cre-dependent Optopatch3 transgenic mouse. b, Representative traces for all-optical electrophysiology recordings in acute brain slices from Optopatch3 transgenic mice crossed with different Cre driver lines. Scale bar, 10 μm. c, Confocal images showing citrine fluorescence from QuasAr3-citrine, in offspring of crosses between Optopatch3 mice and different Cre driver mice. Acute brain slices were prepared from mice aged 14 to 17 days and imaged in the cortex. Scale bar, 50 μm. d, Composite bright-field image of a coronal brain slice from an Rbp4-cre+/−;Optopatch3+/− transgenic mouse, with locations of optical recordings marked with white spots. e, Spike raster showing 94 cells recorded sequentially from a single Rbp4-cre+/−;Optopatch3+/− acute brain slice. f, Optogenetic stimulus intensity-dependent firing rates in acute slices with different Cre drivers. Left, slices that are homozygous for Optopatch3. Right, slices that are heterozygous for Optopatch3. g, Mean firing rate (F), during a 500-ms stimulus as a function of stimulus intensity (I) calculated from the data shown in f. Data are shown as mean ± s.e.m. In the mice with Optopatch3 expression driven by CamKII-Cre, the F–I curve for the Optopatch3+/+ mice is compressed along the x axis relative to the Optopatch3+/− mice, which indicates a stronger optogenetic drive for a given optical stimulation strength in the mice homozygous for CheRiff. The decrease in firing rate at a strong stimulus in these mice is a signature of depolarization block. Data are from 128 cells from 5 slices from 2 SST-cre+/−;Optopatch3+/− mice; 25 cells from 1 slice from 1 CamKII-cre+/−;Optopatch3+/− mouse; 152 cells from 6 slices from 4 Rbp4-cre+/−;Optopatch3+/− mice; 89 cells from 2 slices from 2 mice for CamKII-cre+/−;Optopatch3+/− mice.
