Figure 6.

GlyT2-GFP-expressing dendrites receive negligible inputs from MLI axons. A, Maximum intensity projection image of a confocal image Z-stack of an in vitro recorded and biocytin (red)-labeled MLI with axons spreading among GlyT2-GFP-expressing processes (green). Scale bar: A (for A–C), 10 μm. B, Neurolucida reconstruction of the soma and axon of the recorded cell (red; black circles indicate varicosities; green circles indicate varicosities next to GlyT2-GFP-expressing dendrites). The number of reconstructed cells and the percentage occurrence of each varicosity type are indicated. C, Boxed area in A shown as a series of confocal image planes highlighting a single putative contact (green arrow). Note that most varicosities of the biocytin-filled axon have unlabeled targets, despite numerous GlyT2-GFP-expressing structures in the vicinity. D, Neurolucida reconstruction of a different MLI (soma and dendrites in blue, axon in red). Scale bar, 50 μm. Boxed regions correspond to the fluorescent images shown in E (left) and F (right). E, The axon of the MLI in D makes a bouton in apposition (red) to a calbindin-immunoreactive (CB; cyan) Purkinje cell dendrite. F, The same axon also has several boutons in close apposition with a weakly GlyT2-GFP-labeled MLI soma (GFP; green). Scale bar: F (for E, F), 5 μm.