The objective of this research project is to identify the cellular and molecular mechanisms that control the differentiation of distinct classes of cells at specific position in the central nervous system. We will mainly focus our attention on the mechanisms and molecules that regulate floor plate differentiation in vivo. There is increasing evidence that other signals in addition to the one of Sonic Hedgehog may play an important role in specifying the time and position of floor plate differentiation in vivo (for details see the research project). Three types of experiments are planned. We will try:
- 1) to elucidate the possible role of the paraxial mesoderm as regulator of floor plate differentiation. The putative inhibitory effect of the paraxial mesoderm on floor plate differentiation will be assayed using the in vitro model of the isolated chicken neural plate I have developed in P. Gruss'laboratory;
- 2) to identify the mechanism and putative signal intrinsic to the neural tube responsible for the inhibition of floor plate differentiation in transgenic mice misexpressing Pax3;
-3) to look for other molecules expressed in the notochord possibly involved in ventral cell types differentiation using the differential cloning procedure (DDRT-PCR) on notochord with and without inducing capacities.
This research work should allow us to clarify the mechanisms and, enable us to identify new molecules involved in the regulation of the dorsoventral patterning of the central nervous system. Originating from a less favoured region (Midi-Pyrenees) I plan to go back (1996) to my previous institute in order to apply the knowledge I acquired during my post-doctoral training. Furthermore, this return grant should allow me to continue my research project in an independent manner which will help to obtain a permanent position at the home institution.