Fig. 7
Tufted cell axons project specifically to MCLPN soma locations. a Axonal projections from superficially located TCs traverse the EPL in a column-like arrangement towards the IPL, next to the cluster of the MCLPNs of the same glomerular domain. The same color code is used as in Fig. 6b, indicating different cell types. Red and cyan spheres show the soma positions of MCs and dTCs, respectively. No recurrent axon collaterals from MCs and only minor contributions from dTCs can be found. By far, most axonal branches arise from sTCs. Scale bar = 100 µm. b Example of a 3D-rendered MC (red) and two corresponding sTCs (magenta), which project their axons (“ax”) specifically to the IPL adjacent to the position of the MC, where they support a local collateral mesh. Inset box showing a maximum projection view of the local IPL (depth = 60 µm) next to the MC from a CLSM image stack. Scale bar = 50 µm. c Local axonal IPL mask with positions of the corresponding MCLPNs of the same experiment shown as an overlay (transparent green circles indicating MCs, transparent green triangles marking dTCs). Color bar representing average pixel values ranging from 0 to 1. d Overlay of MCLPN positions form the other two experiments indicated as an intrinsic “shuffled” control (transparent red circles indicating MCs, transparent red triangles marking dTCs). Scale bars = 100 µm. e Normalized pixel counts of all MCLPNs of the three experiments (“matching,” = green lining, MCs = red filled circles, dTCs = cyan filled triangles) are compared to counts of non-matching MCLPN positions from the other two experiments (“control,” = red lining). f, g Same comparison shown for MCs and dTCs individually. Mean values ± s.d. shown in blue. Two-sample t test, **p < 0.01, ***p < 0.001
