CHARACTERIZATION OF NERVANA, A DROSOPHILA-MELANOGASTER NEURON-SPECIFIC GLYCOPROTEIN ANTIGEN RECOGNIZED BY ANTI-HORSERADISH PEROXIDASE ANTIBODIES

Antibodies to the plant glycoprotein horseradish peroxidase (HRP) are used extensively to identify neurons in Drosophila and other insects. We are interested in characterizing the gene product(s) recognized by anti-HRP antibodies because it may be important for nervous system fun ction and/or development. Here we identify and purify from adult Droso phila heads an anti-HRP-reactive M(r) 42K glycoprotein that is likely to be the major contributor to neuronal specific anti-HRP staining. Se veral different monoclonal antibodies to the purified 42K glycoprotein recognize up to three proteins with distinct mobilities between M(r) 38K and 42K that vary as a function of developmental age. We have coll ectively named these components Nervana (nerve antigen), because the m onoclonal antibodies also specifically stain cultured neurons and embr yonic nervous system with a pattern indistinguishable from anti-HRP st aining. Western blots indicate the presence of immunologically similar proteins in a wide variety of insect species and in nac (neurally alt ered carbohydrate) mutant Drosophila flies that lack anti-HRP staining in adult nervous system. It should now be possible to undertake a ful l biochemical and functional characterization of Nervana in Drosophila .