Research Abstract |
Neuronal Ca^<2+> /calmodulin-dependent protein kinase II (CaM kinase II) regulates important neuronal functions, including neurotransmitter synthesis and neurotransmitter release, modulation of ion channel activity, synaptic plasticity, and gene expression. The following results were obtained in this study; 1. when CaM kinase II was introduced in neuronal cells, neurite outgrowth was stimulated, indicating that CaM kinase II played a role stimulation of neurite outgrowth; 2. Ca^<2+> independent activity of the kinase autophosphorylated at Thr-286 involved in neurite outgrowth; 3. more than 28 protein substrates of CaM kinase II were found in the postsynaptic density (PSD), and almost all of these proteins were identified by protein sequencing and mass spectrometry; 4. when the developmental change of the kinase was investigated during the neural differentiation of cultured cells, it was found that CaM kinase II was upregulated during the neuronal differentiation; 5. cell type distinctive changes of splicing pattern of δ isoform were found not only during development of rat brain tissue, but also during differentiation of cultured neuronal cells, indicating that alternatively spliced variants of δ isoform of CaM kinase II were expressed during neural differentiation; 6. when we used the deletion mutants for β-specific insertions to explore the difference between α and β CaM kinase II in enzymatic properties, it was found that β specific insertion of β CaM kinase II played an important role in the cellular distribution of the kinase; 7 The gene encoding the β isoform of rat Ca^<2+>/calmodulin-dependent protein kinase II was cloned, and its structure and exon-intron organization were determined; 8. When the promoter activity of the gene was analyzed using nueronal and non-neuronal cells, neuronal cell type-specific promoter activity was found in the 5'-upstream region of the gene.
|