Nerve cells of Drosophila Notch mutant are differentiated inside amphibian brain: a new approach for the analysis of genetic control of nerve cell differentiation.

Fragments of the neural primordium of a new Notch mutant of Drosophila melanogaster produced in our laboratory were transplanted into the neural tube of embryos of 4 amphibian species (caudate and ecaudate) immediately after completion of neurulation. The grafts were identified by using a light microscope, scanning electron miscroscope, and in situ hybridization with mobile genetic elements of Drosophila and fluorescent dyes as markers. As has been shown, Drosophila nerve cells survive and differentiate inside the neural tube of amphibian embryos. The grafts increase in size by twentyfold and the cell proliferation zones are retained during the period of six months. Differentiated cells of the graft formed axon-dendritic contacts with recipient cells and penetrated into the organisms' brain structures. The effect of Drosophila transplants proved to be different for caudate and ecaudate amphibians. The presence of the graft accelerated the development of Xenopus laevis and it also affected their behavior. This approach can be very useful for the study of genetic basis of development and behavior.