Expression and regulation ofmRNAs for glutamic acid decarboxylase and a neuronal protein kinase in mammalian brain

This dissertation examines the expression of the genes encoding the 65 kD subunit of glutamic acid decarboxylase (GAD) and the alpha subunit of calcium calmodulin dependent protein kinase type II (CaM) in the rat, cat and monkey. Polymerase chain reaction amplification was used to generate cDNA clones to make antisense RNA probes. A second form of CaM {dollar}alpha{dollar}, CaM {dollar}alpha{dollar}-33, that contains an additional phosphorylation consensus sequence was identified. In situ hybridization histochemistry, using cRNA probes, revealed a complementarity in the distributions of cells that showed gene expression for GAD or CaM {dollar}alpha{dollar} throughout the central nervous system of the rat and in the basal ganglia, thalamus, hypothalamus in the monkey. Cells in certain nuclei such as the thalamic reticular nucleus show GAD gene expression only; others such as the dorsal thalamic nuclei in the rat show CaM {dollar}alpha{dollar} gene expression only. Several regions contained both GAD and CaM {dollar}alpha{dollar} expressing cells. However, simultaneous immunolabeling for both proteins in the rat revealed only two regions where CaM and GAD were colocalized, Purkinje cells and the commissural nucleus of the stria terminalis. Collectively, these data imply that CaM {dollar}alpha{dollar} is primarily localized to a population of neurons exclusive of GAD and in several regions is concentrated in regions known to contain excitatory neurons.; In situ hybridization revealed large amounts of CaM {dollar}alpha{dollar} mRNA in the neuropil of most nuclei containing CaM {dollar}alpha{dollar} positive cells. Specific lesions in the hippocampus revealed that neuropil labeling in the CA3 field is associated with dendrites. The message may thus be translated at sites close to synapses.; In situ hybridization in cortex from monkeys that had been monocularly deprived, revealed enhanced CaM {dollar}alpha{dollar} mRNA levels in deprived eye columns of layer IVC and associated with the deprived eye, cytochrome oxidase stained periodicities in other layers. By contrast, GAD mRNA levels appeared unchanged in all layers, suggesting a posttranscriptional regulatory mechanism. In addition, GAD cRNA hybridization in normal visual cortex revealed a complex sub-laminar organization of GAD expressing cells. Monocular deprivation in cats, like the monkey revealed no change in GAD expression.