The cytoskeleton is essential for both axonal and dendritic extension and for neuronal migration. Thus, the formation of a polarized neuronal morphology is ultimately dependent on the cytoskeleton. Dr. Rivas is using the developing mouse cerebellar cortex to study the mechanisms that generate neuronal polarity. Many neurons in the developing vertebrate brain move from proliferative zones by migrating along radial glial fibers to the layers where they establish synaptic contacts. Cerebellar granule neuron migration is an extremely important model for glial-guided migration.
Dendrites extend from the cell body after the completion of migration.
Thus, axonal process formation is segregated both spatially and temporally from cell body migration and dendrite formation. The aim is to understand how the granule neuron forms this morphology. To study these questions workers in Dr. Rivas' laboratory are using a combination of advanced imaging, molecular biological, biochemical, and cell culture techniques, including video and confocal microscopy of living neurons, neuronal cell and brain slice culture, implantation of living neurons into the brain, DNA in vitro mutagenesis and transfection, metabolic labeling, immunohistochemistry, radioimmunoassay, and gel electrophoresis and immunoprecipitation. In vitro effects of somatostatin and urotensin II on prolactin and growth hormone secretion in tilapia, Oreochromis mossambicus. Rivas, R. J. and Moore, H.-P. H., Spatial segregation of the constitutive and regulated secretory pathways.