Extended Data Fig. 8: Awake head-fixed two photon imaging of the visual cortex reveals visual representation changes induced by Cre-dependent eGFP-GluA2 expression in PV interneurons.
From: Calcium-permeable AMPA receptors govern PV neuron feature selectivity
a, Reinforced headposts with light-proofing rings to allow visual stimulation during two photon imaging. b, Circular treadmill for head-fixed awake imaging. The frame is mounted on a pair of goniometers to allow arbitrary tilt correction. c, Venn diagram displaying the hierarchical grouping of visual cortex units based on the responsivity to drifting grating stimuli and valence of largest response. Blue arrows indicate the level at which each analysis or visualization is carried out. d, Epifluorescence image of mouse visual cortex through an implanted cranial window (left) and two-photon imaging within the monocular V1 area (right). Scale bar, 20 μm. e, Experimental schedule. f, Fraction of neurons with statistically significant visual response in CaMKIIα or PV interneurons in each group (0.85, 0.79, 0.76; n = 395/316/355 neurons from 3/6/7 mice, \({{\rm{\chi }}}_{(2)}^{2}\) = 8.4242, dF = 2, P = 1.487x10−2, Chi-square test). g, Average response amplitudes (∆F/F, mean ± SEM) of each group. CaMKIIα+ neurons in the CaMKIIα-Cre mice displayed higher amplitude preferred responses compared to PV interneurons in the PV-Cre;lsl-eGFP and PV-Cre;lsl-eGFP-GluA2 group (n = 202/215/197 neurons, \({{\rm{\chi }}}_{(2)}^{2}\) = 96.78, P = 9.663×10−22, KW 1-way ANOVA; P < 0.0001 for all post-hoc comparisons with CaMKIIα-Cre, Dunn’s multiple comparison correction). h-j, Waterfall plots displaying the overall visual response profile of the population of visually responsive neurons with positive preferred stimulus responses in the (h) CaMKIIα-Cre, (i) PV-Cre;lsl-eGFP, (j) PV-Cre;lsl-eGFP-GluA2 groups. k-n, Mouse-level statistics confirm that removal of CP-AMPARs in PV interneurons increases feature selectivity in layer 2/3 of mouse visual cortex. k, CaMKIIα neurons in the CaMKIIα-Cre mice displayed higher orientation selectivity compared to PV interneurons in PV-Cre;lsl-eGFP mice, and the PV-Cre;lsl-eGFP-GluA2 group showed higher OSI than PV-Cre;lsl-eGFP controls (n = 3/6/7 mice, P = 0.0005, one-way ANOVA; P = 0.0111 for PV-Cre;lsl-eGFP vs. PV-Cre;lsl-eGFP-GluA2 and P = 0.0005 for CaMKIIα-Cre vs. PV-Cre;lsl-eGFP, Tukey’s multiple comparison correction). l, The PV-Cre;lsl-eGFP-GluA2 group showed higher DSI than PV-Cre;lsl-eGFP controls (P = 0.0278, one-way ANOVA; P = 0.0315 for PV-Cre;lsl-eGFP vs. PV-Cre;lsl-eGFP-GluA2). m, Fraction of neurons with statistically significant visual response in CaMKIIα or PV interneurons in each group were not different (0.86, 0.71, 0.71; n = 3/6/7 mice, P = 0.4016, one-way ANOVA). n, Average response amplitudes (∆F/F) of each group. CaMKIIα+ neurons in the CaMKIIα-Cre mice displayed higher amplitude preferred responses compared to PV interneurons in the PV-Cre;lsl-eGFP and PV-Cre;lsl-eGFP-GluA2 group (n = 3/6/7 mice, P < 0.0001, one-way ANOVA; P = 0.0001 for CaMKIIα-Cre vs. PV-Cre;lsl-eGFP and P = 0.0004 for CaMKIIα-Cre vs. PV-Cre;lsl-eGFP-GluA2, Tukey’s multiple comparison correction).
