Development of the Xenopus and Zebrafish Retina. (360G-Wellcome-083203_A_07_Z)

The proposed research on mechanisms of neural development, uses the Xenopus and zebrafish retina as model systems. The key goals of this programme of work are: 1. To investigate the embryonic origins of the retina and in particular to elucidate the signalling pathways involved in the multistage induction of the eyefield from uncommitted and multipotent ectodermal tissue. 2. To characterize the role of the Zic transcription factors in optic cup proliferation and patterning, and to underst and the interaction of Zic proteins as putative integrators of Hedgehog and Wnt signalling in this process. 3. To probe the mechanisms of interkinetic nuclear migration that characterizes proliferating neuroepithelial cells in the retina. 4. To uncover the mechanism by which Hedgehog and Wnt signaling participate in the transition from slow dividing undetermined retinal stem cells to rapidly dividing neural precursors. 5. To extend our knowledge of how specific neurons arise in the reti na by tracing distinct lineages in real time with dynamic imaging in normal and mutant environments. This work continues our longstanding commitment to take advantage of the remarkable opportunities that the vertebrate retina in these model systems provides to open up new issues in the general field of neural development.