Supplementary Figure 1: Selective expression of ChR2 in Purkinje cells in the cerebellar flocculus
From: Cerebellar Purkinje cell activity drives motor learning
To selectively activate Purkinje cells, we expressed channelrhodopsin (ChR2) under the control of the Purkinje cell-specific L7/pcp-2 promoter. (a) Coronal diagram of the mouse cerebellum showing the site of optogenetic stimulation. An optical fiber delivering 473nm (blue) light was sealed to prevent light emission except for where the tip penetrated the brain. Fl, flocculus; PFl, paraflocculus. (b) Targeting of ChR2-EYFP expression to Purkinje cells of the cerebellar flocculus using viral and transgenic approaches. ChR2-EYFP (green) expression in coronal sections corresponding to grey box in (panel a) of an L7-Cre mouse injected with pAAV-EF1α-double floxed-hChR2(H134R)-EYFP (left), and a transgenic mouse resulting from a cross between L7-Cre and Ai32 ChR2 mouse lines (right). With both approaches, a substantial fraction of Purkinje cells in the flocculus expressed ChR2-EYFP. (c) Confocal image of the flocculus of a transgenic mouse (box in panel b, right) shows the extensive overlap (orange) between the membrane bound protein, ChR2-EYFP (green) and antibodies to calbindin (red), which labels the Purkinje cells. Blue, cell bodies stained with DAPI; ML, molecular layer; Pk, Purkinje cell layer.
