Fig. 2.

Bsn cKO mice lack Bassoon in excitatory synapses of the hippocampus. Immunoreactivity of Bassoon (magenta, a, a′), VGLUT1 (green, b, b′) antibodies in hippocampal sections from WT and cKO mice depict the localization of Bassoon in all neuropil layers in WT (c, d) and loss of this immunoreactivity in cKO mice (c′, d′). For comparison, immunoreactivity of Bassoon (magenta, e, e′) and VGAT (green, f, f′) antibodies shown in the hippocampus of both WT (g) and cKO mice (g′) shows a more disparate distribution. Entangled areas from overlay images (high magnification images from molecular layer of DG, h and h′) demonstrate that Bassoon is still expressed in inhibitory synapses (indicated by white arrows). Residual labeling is evident in some non-GABAergic synapses, potentially arising from neuromodulatory afferences. Hi-Magn high magnification. Scale bar in a, e is 500 µm and high magnification d, h is 5 µm