Synaptic Neuropils of the Drosophila Brain

Dr. Xuejun Sun (xjsun@is.dal.ca),
Department of Psychology, Dalhousie University, Halifax NS B3H 4JI, Canada

From the front (ventral according to the neuraxis). Indicated are the superior lateral and superior medial protocerebra (s l pr, s m pr), the left and right protocerebra divided by the pars intercerebralis (pars in). Visible components of the olfactory pathways are the antennal lobes (ant lo), the mushroom body alpha lobe and beta, gamma lobe complex. Su oes g = suboesophageal ganglion.

From below (neuraxis-ventral for the suboesophageal neuropil only). The optic lobes shown with the lamina (la) outer and inner medulla neuropils (me o and me I), the lobula (lo) and the lobula plate (lo p). Optic lobes are confluent with the lateral deutocerebrum (l deu).

From behind (neuraxis dorsal). Calyx neuropil (ca) shows some evidence of its partition into four subunits. The lateral horn (l ho) is shown flanking the calyces (ca). The characteristic profile of the protocerebral bridge (pr br) is situated between the calyces. Note the deep cleft formed by the pars intercerebralis.

Images of the adult brain were captured using a Zeiss LSM 410 confocal (x25 objective, NA 0.8 at 2 mm (adult) steps along the Z axis. Neuropils were visualized after immunocytological labeling with antisynaptotagmin, a synaptic vesicle protein provided by Drs J. T. Littlejohn and H. J. Bellen, and subsequent labelling with Cy3-conjugated secondary antibody.

The movies show the surface views of structures that contain synaptic vesicles. Thus, most axons are absent from these images and the cell body layer is seen as an unstructured "ghost" delineating the whole brain. Antisynaptotagmin provides spectacular views of the optic lobes, showing the very clear division of the medulla into an outer two thirds and inner third, and the divisions of the lobula and lobula plate. The posterior (body axis) view (dorsal according the neuraxis) shows the calyces flanking the m-shaped protocerebral bridge with the lobes of the protocerebrum either side. The frontal view shows the glomeruli of the antennal lobes, the inferior medial protocerebrum partly obscuring the beta- gamma-lobe complex of the mushroom bodies. The left and right superior protocerebral lobes lie above the anterior optic tubercle. The divided head of one of the alpha lobes is visible emerging from the left protocerebrum but appears to be obscured by neuropil of the right protocerebrum. Such slight asymmetries are not uncommon.

Adult
X-axis rotation Quicktime: [large small] MPEG: [large small]
Y-axis rotation Quicktime: [large small] MPEG: [large small]

Flybrain    Atlas    3D Flybrain    Renditions of 3D Structures    Synaptic Neuropils

All contents are copyright © 1995-2000 Flybrain or their original publication (as noted).
Copyright and use policy

AC00158