Fig. 3.

Distinct SC PV⁺ neurons divergently project to the PBGN and LPTN. a Schematic diagram showing AAV-DIO-mGFP injection into the SC of PV-ires-Cre mice. b Coronal section (left) and example micrographs (right) showing specific expression of mGFP in SC PV⁺ neurons. Arrows indicate PV⁺ neurons. Scale bars, 1 mm (left) and 30 μm (right). For quantitative analyses, see Supplementary Fig. 4a. c, d Coronal section (c) and its cropped region (d) showing mGFP⁺ axon terminals of SC PV⁺ neurons in the LPTN and other adjacent thalamic nuclei. For the whole-brain mapping of SC PV⁺ neuron targets, see Supplementary Fig. 4a and 4b. Scale bars, 1 mm (c) and 200 μm (d). e Schematic diagram showing ipsilateral injection of CTB-594 into the LPTN and CTB-488 into the PBGN of the same mice. Scale bar, 1 mm. f Example coronal section of the ipsilateral SC showing the distribution of retrogradely labeled cells projecting to the PBGN (CTB-488⁺, green) and LPTN (CTB-594⁺, red). Scale bar, 0.5 mm. For single-channel micrographs, see Supplementary Fig. 4c. g Example micrographs from Op layer showing a large proportion of PBGN-projecting (CTB-488⁺) and LPTN-projecting neurons (CTB-594⁺) were positive for PV. Arrows indicate CTB-488⁺ and CTB-594⁺ neurons that are also positive for PV. Scale bars, 25 μm. h Quantitative analyses of the laminar distribution of SC PV⁺ neurons projecting to the PBGN (CTB-488⁺) and LPTN (CTB-594⁺). Data in (h) are means ± SEM (error bars, n = 3 mice). Statistical analysis was Student’s t test (***P < 0.001)