In situ hybridization histochemistry of Ca2+/calmodulin-dependent protein kinase in developing rat brain

Abstract

Oligonucleotide DNA probes were used to determine the distribution of mRNAs encoding the alpha- and beta-subunits of Ca2+/calmodulin-dependent protein kinase type II (CaM-KII) in developing rat brain. The regional and temporal distribution of these mRNAs closely paralleled the distribution and developmental appearance previously reported for their respective protein subunits. alpha-Subunit mRNA was barely detectable in sagittal sections at 4 d postnatal but increased as much as 10-fold in frontal cortex by day 16. beta-Subunit mRNA, on the other hand, was readily detected at 4 d postnatal and changed only slightly during development. Telencephalic structures exhibited the highest levels of CaM-KII mRNA and the brain stem displayed the least. alpha-Subunit mRNA was not observed in cerebellar granule cells and was barely detectable in Purkinje cells, while the beta-mRNA was easily detected in both neuronal types. mRNAs for both alpha- and beta-subunits were present in many neuronal cell bodies; however, only the alpha-subunit mRNA was localized to molecular layers of the hippocampus and lamina I of the frontal cortex. These layers of neuropil are relatively cell sparse and contain extensive dendritic arborizations and synaptic contacts. Since polyribosomes have been observed near hippocampal dendritic spines, the localization of alpha-subunit mRNA to dendrites of pyramidal and dentate granule cells suggests that this subunit is synthesized in situ at postsynaptic sites. The co-localization of translational machinery and high concentrations of CaM-KII in postsynaptic elements suggests an important relationship between alpha-subunit synthesis and the maintenance and plasticity of postsynaptic structures.

N-Type Calcium Channels in the Developing Rat Hippocampus: Subunit, Complex, and Regional Expression

“…An intimate relationship between N-V DCC expression and synaptogenesis is supported by changes in -C gT x binding in mouse brain growth cone particles (Vigers and Pfenninger, 1991). C ertainly, the pattern of expression of N-V DCC s, unlike several other voltage-gated ion channels (Yaari et al, 1987;Maletic-Savatic et al, 1995;Scholz and Miller, 1995), is remarkably similar to that of other proteins implicated in synaptic f unction (Burgin et al, 1990;Bahn et al, 1994;L omeli et al, 1994;Melloni et al, 1994;Sheng et al, 1994). Enhanced expression of N-V DCC s during synaptogenesis agrees well with their role in neurotransmitter release (Dunlap et al, 1995;Scholz and Miller, 1995).…”

Repeated confocal imaging of individual dendritic spines in the living hippocampal slice: evidence for changes in length and orientation associated with chemically induced LTP

“…[Although GAP-43 protein is largely concentrated in axons, it has been detected immunohistochemically in the tips of dendritic spines (DiFiglia et al, 1990).] mRNA encoding the a-subunit of CaMKII has also been detected in distal dendrites (Burgin et al, 1990).…”

The Role of Brain-Derived Neurotrophic Factor Receptors in the Mature Hippocampus: Modulation of Long-Term Potentiation through a Presynaptic Mechanism involving TrkB

“…To create a cell-and region-specific mutation of the trkB gene, we used the promoter for ␣CaMKII to generate a transgenic mouse line in which the promoter drives expression of the cre transgene (termed CaMKcre) in the forebrain (Burgin et al, 1990;Mayford et al, 1995). Crossing of fBZ/ϩ and CaMKcre mice led to deletion of the floxed trkB cDNA in cre-expressing cells.…”