Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.17 (CaMKII)
 4,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A combination of either retrograde or anterograde fluorescent tracer and immunofluorescence histochemistry using the monoclonal antibody specific for the alpha isoform of calcium/calmodulin-dependent protein kinase II (CaM kinase II alpha) was employed to test whether CaM kinase II alpha is expressed in somata of corticospinal neurons and their axons over their whole course. After the injection of carbocyanine dye DiI into the hindlimb area of the primary motor cortex of the rat, corticospinal axons and their terminal arbors were anterogradely labeled: DiI-labeled corticospinal fibers proceeded caudally in the ipsilateral internal capsule, cerebral peduncle and medullary pyramid, crossed at the pyramidal decussation and descended in the ventralmost area of the contralateral dorsal funiculus of the spinal cord. These DiI-labeled corticospinal axons expressed strong CaM kinase II alpha immunoreactivity along their course. However, their terminal arbors within the gray matter of the lumbar cord were very weakly immunostained. With the injection of Fast Blue into the lumbar enlargement of the rat, somata of corticospinal neurons in layer V of the motor cortex were retrogradely labeled. The subsequent immunofluorescent histochemistry revealed that more than 80% of Fast Blue-labeled corticospinal neurons were immunostained with CaM kinase II alpha antibody. The present immunohistochemical study demonstrated that CaM kinase II alpha is strongly expressed in both somata and axons of a majority of corticospinal neurons, although we could not detect this enzyme in the corticospinal terminals in the spinal target areas.
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PMID:Alpha calcium/calmodulin-dependent protein kinase II immunoreactivity in corticospinal neurons: combination of axonal transport method and immunofluorescence. 748 9

Following LTP induction in freely moving rats, in situ hybridization revealed discrete changes in the expression of one isoform in each of four families of serine/threonine kinases constitutively expressed in the dentate gyrus of the hippocampus. Expression of the alpha isoform of CaMKII showed a transient increase over the soma and a more persistent increase over the dendritic field of dentate granule cells. Of the PKC isoforms, only gamma PKC was up-regulated substantially 2 hr after LTP induction, declining to control levels 48 hr later. An increase in the expression of mRNA for ERK2 and raf-B was seen at 24 hr only. These results show that, during the maintenance phase of LTP in the hippocampus, there are selective increases in the expression of serine/threonine kinases and that these increases have specific and characteristic temporal and spatial profiles.
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PMID:Spatial and temporal changes in signal transduction pathways during LTP. 791 3

To elucidate the functional role of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) in neuronal cells, we studied the phenotypic effects of overexpression of the CaM kinase II wild-type alpha subunit and a mutant enzyme alpha isoform (Ala-286), in which formation of the Ca(2+)-independent form by autophosphorylation is markedly suppressed by replacement of Thr-286 with Ala, using Neuro2a (Nb2a) and NG108-15 neuroblastoma cell lines. The cDNAs inserted into the EcoRI site of pEF321 expression vector were introduced into Nb2a and NG108-15 cells with pEF321-neo (neo). Stable clones were obtained by G418 selection. The specific activities of CaM kinase II in alpha and Ala-286 transfectants were two to four times higher than those in non-transfectants and in cells transfected with neo alone. Indirect immunofluorescence using a monoclonal antibody specific to the CaM kinase II alpha isoform revealed that CaM kinase II was mainly localized in the perikaryal and dendritic cytoplasm of the alpha and Ala-286 transfectants. Immediately after plating, Nb2a and NG108-15 cells transfected with neo, alpha and Ala-286 cDNAs appeared round. Several hours after plating, alpha transfectants showed cell flattening and initiation of neurite outgrowth, and thereafter extended numerous long and branching neurites. Numerous filopodia protruded from flat growth cones, some of which were accompanied by extensive veil formation. Non- and neo transfectants remained round. In Ala-286 transfectants, however, the phenotypic changes were remarkably less than in alpha transfectants.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Overexpression of Ca2+/calmodulin-dependent protein kinase II in Neuro2a and NG108-15 neuroblastoma cell lines promotes neurite outgrowth and growth cone motility. 838 Nov 67

The enzymatic and regulatory properties of Ca2+/calmodulin-dependent protein kinase in the postsynaptic density (mPSDp CaM kinase) of the rat forebrain was compared with those of soluble Ca2+/calmodulin-dependent protein kinase II (CaM kinase II). mPSDp CaM kinase was different from soluble CaM kinase II in terms of substrate specificity, regulatory consequences and sites of autophosphorylation. Both soluble and PSD kinases generated Ca(2+)-independent activity by autophosphorylation and Ca(2+)-independent activity almost reached the maximum during the first minute of autophosphorylation. Ca(2+)-independent activity of mPSDp CaM kinase was more stable than that of the soluble kinase under autophosphorylating conditions. Autophosphorylation of the kinases decreased the mobility of the kinases on SDS-polyacrylamide gels. The mobility shift and determination of 32P phosphate incorporation into the kinases demonstrated that there were three species in mPSDp CaM kinase alpha isoform: two active forms with and without the mobility shift (about 22 and 19%, respectively), and an inactive form (about 59%). However, there was only one species in the soluble kinase alpha isoform, which was active. The maximum incorporation of 32P phosphate into mPSDp CaM kinase alpha isoform was less than that of the soluble kinase. Tryptic peptide analysis indicated that the phosphorylation sites of mPSDp CaM kinase alpha isoform differed from those of the soluble kinase.
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PMID:Characterization and autophosphorylation of Ca2+/calmodulin-dependent protein kinase in the postsynaptic density of the rat forebrain. 839 Sep 10

The gene for the alpha isoform of Ca2+/calmodulin-dependent kinase II (alpha CaMKII) codes for a multifunctional protein kinase that is found exclusively in the brain. Here we show that in skeletal muscle, an alternative nonkinase product, hereafter referred to as alpha KAP (alpha CaMKII association protein), is expressed from the same gene. alpha KAP consists of a C-terminal region that is identical to the association domain of alpha CaMKII, with the exception of 11 amino acids inserted in the variable region. The N-terminal sequence of alpha KAP is highly hydrophobic and not present in any known CaMKII protein. The catalytic and regulatory domains of alpha CaMKII are missing in alpha KAP. Analysis of the exon-intron structure revealed that the alpha KAP transcript is derived from the alpha CaMKII gene by alternative promoter usage and RNA splicing. The transcriptional start site of alpha KAP mRNA is located within an intron of the alpha CaMKII gene. Therefore, the relationship between alpha KAP and alpha CaMKII is that of a gene within a gene. Immunostaining using anti-alpha KAP antibodies suggests that alpha KAP is associated with sarcomeres of skeletal muscle fibers. On the basis of its primary structure and specific location, the possible function of alpha KAP as an anchoring protein for CaMKII is discussed.
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PMID:An alternative, nonkinase product of the brain-specifically expressed Ca2+/calmodulin-dependent kinase II alpha isoform gene in skeletal muscle. 852 7

Cyclic ADP-ribose (cADPR) is generated in pancreatic islets by glucose stimulation, serving as a second messenger for Ca2+ mobilization from the endoplasmic reticulum for insulin secretion (Takasawa, S., Nata, K., Yonekura, H., and Okamoto, H. (1993) Science 259, 370-373). In the present study, we observed that the addition of calmodulin (CaM) to rat islet microsomes sensitized and activated the cADPR-mediated Ca2+ release. Inhibitors for CaM-dependent protein kinase II (CaM kinase II) completely abolished the glucose-induced insulin secretion as well as the cADPR-mediated and CaM-activated Ca2+ mobilization. Western blot analysis revealed that the microsomes contain the alpha isoform of CaM kinase II but do not contain CaM. When the active 30-kDa chymotryptic fragment of CaM kinase II was added to the microsomes, fully activated cADPR-mediated Ca2+ release was observed in the absence of CaM. These results along with available evidence strongly suggest that CaM kinase II is required to phosphorylate and activate the ryanodine-like receptor, a Ca2+ channel for cADPR as an endogenous activator, for the cADPR-mediated Ca2+ release.
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PMID:Requirement of calmodulin-dependent protein kinase II in cyclic ADP-ribose-mediated intracellular Ca2+ mobilization. 853 Apr 41

The gene encoding the alpha isoform of rat Ca2+/calmodulin-dependent protein kinase II was cloned, and its exon-intron organization was analyzed. The coding region of cDNA consists of 18 exons spanning more than 50 kilobase pairs. Each of the discrete functional units, such as the ATP-binding site, the autophosphorylation site responsible for Ca2+-independent activity, the calmodulin-binding site, and link structure is encoded by a single exon. The largest and smallest exons consist of 229 and 41 base pairs, respectively. All splice junction sequences flanking the introns conform to the consensus splice junction sequence and the GT-AG splice rule.
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PMID:Gene of rat Ca2+/calmodulin-dependent protein kinase II alpha isoform -- its cloning and whole structure. 891 14

Since the alpha and beta isoforms of CaM kinase II are known to be expressed almost exclusively in the brain, we compared the effect of overexpression of the beta isoform of CaM kinase II with that of the alpha isoform. The subcellular distribution of the alpha isoform was different from that of the beta isoform, although the catalytic properties of the alpha and beta isoforms expressed in transfected cells were similar to those of brain CaM kinase II. The alpha isoform was found in the soluble fraction more than in the particulate fraction, whereas most of the beta isoform bound to subcellular structures. In the cell overexpressing alpha and beta isoforms of CaM kinase II, neurite extension was promoted when compared with the morphology of neo transfectants. Neurite outgrowth of cells overexpressing CaM kinase II was further stimulated by the treatment of 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7), a selective but not absolutely specific inhibitor of protein kinase C. The morphological change was rapid and observed within 1 h followed by H-7 treatment. Morphological changes, such as the number of cells with neurites and length of neurites were greater in the beta cells than in the alpha cells. Chelerythrine, a specific inhibitor of protein kinase C, also stimulated the neurite outgrowth of these cells. Some substrates of CaM kinase II related to neurite outgrowth were detected in cells overexpressing CaM kinase II stimulated with H-7. These results suggest that CaM kinase H and protein kinase C play an important role in the control of cell change, and that the subcellular distribution of CaM kinase II is important for regulating cellular functions efficiently.
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PMID:Overexpression of alpha and beta isoforms of Ca2+/calmodulin-dependent protein kinase II in neuroblastoma cells -- H-7 promotes neurite outgrowth. 935 96

Immortalized hybrid cells were generated by the somatic fusion of the cells from the forebrain of embryonic mouse with N18TG2 neuroblastoma cells. Three monoclonal hybrid cell lines, designated NF26, NF81, and NF83 (neuroblastoma forebrain hybrid cells), expressing an alpha isoform of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) were isolated, and their expression was demonstrated by immunoblotting and immunocytochemistry using a monoclonal antibody specific to the a isoform of the enzyme. The kinase activity of the hybrid cells was 2- to 3-fold higher than that of the parent neuroblastoma line N18TG2 cells. The neuronal origin of these lines was shown by their immunoreactivity to neurofilament protein, a neuron specific marker. Lines NF26, NF81, and NF83 are the first cell lines to express the gene of the alpha isoform of CaM kinase II in the brain.
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PMID:Generation of immortalized murine forebrain cell lines expressing an alpha isoform of Ca2+/calmodulin-dependent protein kinase II. 955 46

The distribution of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) alpha and beta isoforms in the brainstem of adult rats was investigated using an immunohistochemical method with two monoclonal antibodies which specifically recognize the alpha and beta isoform, respectively. We found that these isoforms were differentially expressed by neurons in the substantia nigra, red nucleus, dorsal cochlear nucleus, pontine nuclei and inferior olivary nucleus. Neurons in the inferior olivary nucleus express the alpha isoform, but not the beta isoform. In contrast, neurons in the substantia nigra, red nucleus and pontine nuclei were immunostained with the beta antibody, but not with the alpha antibody. In the dorsal cochlear nucleus, neurons in layers I and II were alpha-immunopositive, whereas neurons in layers III and IV were beta-immunopositive. Therefore, the distribution of the CaM kinase II alpha-immunopositive neurons is completely different from that of CaM kinase II beta-immunopositive neurons. Next we examined the possible coexistence of CaM kinase II alpha isoform and glutamate or that of CaM kinase II beta isoform and glutamic acid decarboxylase (GAD) in the single neuron by double immunofluorescence labelling using a pair of anti-alpha and anti-glutamate antibodies, or a pair of anti-beta and anti-GAD antibodies. The results indicated that neurons expressing anti-alpha immunoreactivity were also immunopositive against anti-glutamate antibody, and neurons expressing beta isoform were also immunopositive against anti-GAD antibody, suggesting that alpha-immunopositive neurons are classified as excitatory-type neurons, and on the contrary, beta-immunopositive neurons are classified as inhibitory-type neurons. In conclusion, the present study confirmed that alpha- and beta-isoforms of CaM kinase II are differentially expressed in the nuclei of the brainstem and have different roles.
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PMID:Regional differences between the immunohistochemical distribution of Ca2+/calmodulin-dependent protein kinase II alpha and beta isoforms in the brainstem of the rat. 959 59


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