J. Lichtenfeld et al., NEURAL STRUCTURES IN AN INSECT EMBRYO (SCHISTOCERCA-GREGARIA) REVEALED BY AN ANTISERUM AGAINST A VERTEBRATE GLIAL GLYCOPROTEIN, Zoology, 101(2), 1998, pp. 83-93
A number of specific molecular cues play important roles in guiding pa
rticular axons towards selected target locations in the nervous system
. It is remarkable that many of these well-known molecules, whether re
ceptors or chemoattractants/repulsants are highly conserved among inve
rtebrates and vertebrates. Here, we demonstrate labeling of the grassh
opper Schistocerca gregaria embryo with an antiserum raised against bo
vine Reissner's substance, a glycoprotein which is described in verteb
rates as a secretory product of radial glial cells. The Reissner's sub
stance-like immunoreactivity shows temporal expression during embryoni
c development of the central nervous system in the grasshopper. The ea
rliest labeling is on processes of the midline precursor 2 progeny at
approximatly 29% of embryonic development. At more advanced stages the
antigen revealed localisation in the main axon scaffold of the brain
and segmentally repeated ganglia. Apparently, the relevant molecule is
produced from cells located dorsally of the neural lamina and is accu
mulated in the extracellular matrix of the ganglionic neuropil. We sug
gest that the labeled antigen has molecular mutualities and relations
to the glial glycoprotein of vertebrates. The early and common express
ion favours a basic function in correlation with the development of a
complex nervous system throughout the animal kingdom.