9808656 LALLIER The formation of the vertebrate central nervous system is characterized by two major cellular processes: 1) the instruction of the ectoderm to differentiate into nerve cells (neural induction), and 2) the movement of this ectoderm from the surface of the embryo into the interior (neurulation). While much is understood about the cellular mechanism underlying the first, little is known about the second. Dr. Lallier will investigate how the cells of the future brain and spinal cord move inside of the embryo using the frog Xenopus laevis as his model system. Dr. Lallier has previously demonstrated that a cell- surface molecule called alpha-6 integrin is necessary for neurulation. Alpha-6 integrin helps anchor presumptive neural ectoderm to its extracellular environment; specifically, to the axon stimulating molecule laminin. The present studies are aimed at discovering whether this molecule is required for neural induction or neurulation. Preliminary data suggest that the alpha- 6 integrin is not required for the induction of a series of genes expressed specifically during the early phases of neural induction. Therefore an in depth study of the role of alpha-6 integrin in the cellular and mechanical events of neurulation are planned. These results will enable researchers to better understand this essential early developmental event in the formation of the nervous system.
