Figure 4.

Afferent connections of dorsoventral neuromasts. A, In a maximal-intensity projection of a confocal Z-stack, the mCherry-expressing afferent fiber turns ventrally from the lateral-line nerve to reach a dorsoventral neuromast. B, The hair cells in the same neuromast are labeled with GFP (green). C, D, This neuromast contains 10 hair cells, of which four receive bulbous synaptic endings. The most rostral is contacted by only a thin neurite (arrowhead). E, Labeling with fluorescent phalloidin indicates that these five hair cells have ventrally polarized hair bundles. Although the dorsally polarized hair cells are embraced by a thin, circular extension of the neuron (A), they lack synaptic boutons. Scale bars, 5 μm.