Establishment of a Primary Axon Scaffold

(A,C) Sections, (BDF) whole mounts, (E) laser confocal microscopy. Axon-specific monoclonal antibody BP102 immunoreactivity (A,B), Fasciclin II immunoreactivity (C,F), Fasciclin I immunoreactivity (D,E).

(A,B) Quasiorthogonal axon scaffold is established in the brain. Note the paired circumesophageal connectives (arrowhead) around foregut, preoral commissure (filled arrow) above foregut, postoral tritocerebral commissure (open arrow) below foregut and the adjacent three commissures of the subesophageal ganglion in (A). The frontal views are in plane of both circumesophageal connectives.
(C) Discrete Fasciclin II-expressing axon fascicles in longitudinal (arrowheads) and commissural (arrows) brain pathways. This frontal section is in plane with both circumesophageal connectives.
(D) Pioneer neurons of the brain commisure express Fasciclin I. A pair of neuronal cell bodies on each side of the brain (right pair labelled with arrowheads) project the first brain commissural axons across the midline (arrow) and fasciculate with their homologs.
(E) Many axons in the preoral brain commissure and several fascicles and neurons in the two brain hemispheres show fasciclin I immunostaining. The non-commissural immunoreactive midline structures (asterisks) belong to the stomatogastric system.
(F) Two fascicles in the primary preoral commissure (Arrow) show Fasciclin II immunostaining. The non-commissural midline structures (asterisks) belong to the stomatogastric and the neuroendocrine systems. This is a dorsal view of an embryo with the anterior end downwards.
Stages 16 (A,B,C,E,F), 13 (D). Scale bar, 10.

Flybrain    Development    Embryonic Brain Development    Formation of Commissural and Descending Pathways    Primary Axon Scaffold

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

AB00105