Fig. 6.

n-syb null eye mosaics. A, Twin spot in a fly’s eye. The white patch marks photoreceptors without neuronal synaptobrevin; red patches correspond to homozygous wild-type synaptobrevin; andorange marks the heterozygous background.B, View onto a three-dimensional reconstruction of the distal medulla (viewed from the eye) of the same specimen as inA in a staining with anti-chaoptin. Although all photoreceptor terminals exhibit chaoptin immunoreactivity, a patch of exactly the same shape as the white eye spot exhibits significantly stronger immunoreactivity. C, Anti-FasII staining of another specimen with a white eye spot. A restricted area of strong Fasciclin II immunoreactivity in photoreceptors is visible.D, 3D reconstruction of a patch of Fasciclin II-positive photoreceptor terminals in the distal medulla reveals many overlaps of arborizations (arrow). R7,R8, Photoreceptor terminals. Scale bars, 20 μm.