Extended Data Fig. 2. Mapping the brainwide targets of CSNsDLS.
(A) Experimental strategy to label corticospinal neurons that project to striatum (CSNsDLS). (B) Photomicrographs exemplifying the cortical distribution CSNsDLS. Representative of N=3. (C) Sagittal Z projection of raw fluorescence aligned to atlas space. Representative of N=3. (D) 3D reconstruction of CSNsDLS cell bodies. Representative of N=3. (E) Quantification of cortical regions contributing to the total population of CSNsDLS, compared to experiments from Figure 1 targeting primarily the motor cortical population of CSNs (M-CSNs). Asterisks indicate statistically significant differences in innervation between M-CSNs and CSNsDLS (*: p<0.05, **: p<0.005, 2-way ANOVA with post-hoc t-test). (F) Quantification of brain regions targeted by CSNsDLS, compared to data from Figure 1. Note that – despite the differences in experimental strategy – DLS is a primary target of CSNsDLS. N=3. (G) 3D reconstruction of CSNsDLS projections throughout the brain, colored by targeted brain region. (H) Photomicrograph showing CSNsDLS axon labeling in the brainstem. Representative of N=3. (I) Higher magnification inset from (H). Representative of N=3. (J) Experimental strategy to drive expression of GFP in corticospinal neurons that form synapses on identified spinal cell types. (K) 3D reconstruction of axons from CSNsChx10, color coded by brain region. (L) Confocal micrograph exemplifying CSNChx10 axon labeling in DLS. (M) Quantification of brain structures that receive substantial input from CSN subtypes. N=4, Chx10, N=2, SST, N=3, GAD2. Error bars are SEM.