The lipid binding, regulatory domain of protein kinase C. A 32-kDa fragment contains the calcium- and phosphatidylserine-dependent phorbol diester binding activity.

✓ Vasospasm was produced in adult mongrel dogs by a two-hemorrhage method, and the spastic basilar arteries were exposed via the transclival route on Day 7. Tonic contraction was produced in the normal canine basilar arteries by a local application of KCl or serotonin after transclival exposure. The exposed spastic and tonic basilar arteries then received a topical application of the following: 1-(5-isoquinolinesulfonyl)-2-methyl-piperazine (H-7), a potent inhibitor of protein kinase C acting at the catalytic domain; calphostin C, a specific inhibitor of protein kinase C acting at the regulatory domain; or calpeptin, a selective inhibitor of calpain. Both spastic and tonic basilar arteries were effectively dilated by H-7. Calphostin C caused only slight dilation of spastic basilar arteries but moderate dilation of tonic basilar arteries. Dilation in response to calpeptin was remarkable in the spastic basilar arteries but slight in the tonic basilar arteries. The doses of calphostin C and calpeptin required to obtain maximum effect were markedly lower in the tonic model than in the spastic model. The spastic and tonic models had a similar dose-dependent response to H-7 but quite a different response to calphostin C or calpeptin, suggesting a difference in the function of protein kinase C and calpain in the two models. Furthermore, the effect of calphostin C on the reversal of vasospasm was increased significantly after topical treatment with calpeptin. It is suggested that the majority of the catalytic domain of protein kinase C is dissociated from the regulatory domain, probably by a limited proteolysis with calpain, and is markedly activated in vasospasm.

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The regulatory domain of protein kinase C delta positively regulates insulin receptor signaling

Journal of Molecular Endocrinology ◽

10.1677/jme-09-0119 ◽

2009 ◽

Vol 44 (3) ◽

pp. 155-169 ◽

Cited By ~ 9

Author(s):

Avraham I Jacob ◽

Miriam Horovitz-Fried ◽

Shlomit Aga-Mizrachi ◽

Tamar Brutman-Barazani ◽

Hana Okhrimenko ◽

...

Keyword(s):

Skeletal Muscle ◽

Protein Kinase C ◽

Protein Kinase ◽

Insulin Receptor ◽

Glycogen Synthase ◽

Regulatory Domain ◽

Protein Kinase C Delta ◽

Kinase C ◽

Regulatory Effects ◽

In Cells

Protein kinase C delta (PKCδ) is induced by insulin to rapidly associate with insulin receptor (IR) and upregulates insulin signaling. We utilized specific JM and CT receptor domains and chimeras of PKCα and PKCδ regulatory and catalytic domains to elucidate which components of PKCδ are responsible for positive regulatory effects of PKCδ on IR signaling. Studies were performed on L6 and L8 skeletal muscle myoblasts and myotubes. PKCδ was preferentially bound to the JM domain of IR, and insulin stimulation increased this binding. Both PKCδ/α and PKCα/δ chimeras (regulatory/catalytic) were bound preferentially to the JM but not to the CT domain of IR. Although IR–PKCδ binding was higher in cells expressing either the PKCδ/α or PKCα/δ chimera than in control cells, upregulation of IR signaling was observed only in PKCδ/α cells. Thus, in response to insulin increases in tyrosine phosphorylation of IR and insulin receptor substrate-1, downstream signaling to protein kinase B and glycogen synthase kinase 3 (GSK3) and glucose uptake were greater in cells overexpressing PKCδ/α and the PKCδ/δ domains than in cells expressing the PKCα/δ domains. Basal binding of Src to PKCδ was higher in both PKCδ/α- and PKCα/δ-expressing cells compared to control. Binding of Src to IR was decreased in PKCα/δ cells but remained elevated in the PKCδ/α cells in response to insulin. Finally, insulin increased Src activity in PKCδ/α-expressing cells but decreased it in PKCα/δ-expressing cells. Thus, the regulatory domain of PKCδ via interaction with Src appears to determine the role of PKCδ as a positive regulator of IR signaling in skeletal muscle.

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Caerulein-induced NF-κB/Rel activation requires both Ca2+ and protein kinase C as messengers

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1999.277.3.g678 ◽

1999 ◽

Vol 277 (3) ◽

pp. G678-G686 ◽

Cited By ~ 16

Author(s):

Yusuke Tando ◽

Hana Algül ◽

Martin Wagner ◽

Hans Weidenbach ◽

Guido Adler ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Nuclear Translocation ◽

Inhibitory Effect ◽

Binding Activity ◽

Atpase Inhibitor ◽

Kinase C ◽

Protein Kinase C Activity ◽

Intracellular Ca ◽

Iκbα Degradation

The eukaryotic transcription factor NF-κB/Rel is activated by a large variety of stimuli. We have recently shown that NF-κB/Rel is induced during the course of caerulein pancreatitis. Here, we show that activation of NF-κB/Rel by caerulein, a CCK analog, requires increasing intracellular Ca2+ levels and protein kinase C activation. Caerulein induces a dose-dependent increase of nuclear NF-κB/Rel binding activity in pancreatic lobules, which is paralleled by degradation of IκBα. IκBβ was only slightly affected by caerulein treatment. Consistent with an involvement of Ca2+, the endoplasmic reticulum-resident Ca2+-ATPase inhibitor thapsigargin activated NF-κB/Rel in pancreatic lobules. The intracellular Ca2+ chelator TMB-8 prevented IκBα degradation and subsequent nuclear translocation of NF-κB/Rel induced by caerulein. BAPTA-AM was less effective. Cyclosporin A, a Ca2+/calmodulin-dependent protein phosphatase (PP2B) inhibitor, decreased caerulein-induced NF-κB/Rel activation and IκBα degradation. The inhibitory effect of bisindolylmaleimide suggests that protein kinase C activity is also required for caerulein-induced NF-κB/Rel activation. These data suggest that Ca2+- as well as protein kinase C-dependent mechanisms are required for caerulein-induced NF-κB/Rel activation.

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Modulation of cofactor requirement for the activation of protein kinase C by heparin Possible effect at the regulatory domain

FEBS Letters ◽

10.1016/0014-5793(91)80533-9 ◽

1991 ◽

Vol 282 (2) ◽

pp. 445-448 ◽

Cited By ~ 6

Author(s):

Said A. Goueli ◽

John A. Hanten ◽

Khalil Ahmed

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Regulatory Domain ◽

Kinase C

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Bifemelane induces translocation of protein kinase C in the CA3, but not the CA1, region of guinea-pig hippocampus

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y90-058 ◽

1990 ◽

Vol 68 (3) ◽

pp. 413-418 ◽

Cited By ~ 7

Author(s):

Takeshi Fujii ◽

Yasushi Kuraishi ◽

Toshikazu Okada ◽

Masamichi Satoh

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Guinea Pig ◽

Long Term Potentiation ◽

Binding Activity ◽

Ca1 Region ◽

Kinase C ◽

Term Potentiation ◽

Ca3 Region

We made use of the [3H]phorbol 12,13-dibutyrate binding assay to investigate the effects of bifemelane on the subcellular distribution of protein kinase C in the CA3 and CA1 regions of guinea-pig hippocampal slices. Bifemelane, a drug that augments the long-term potentiation in the CA3 region, significantly induced the translocation of [3H]phorbol 12,13-dibutyrate binding activity from the cytosol to the membrane in a dose-dependent manner (10−8 to 10−6 M) and with no effects on total binding activity in the CA3 region. Bifemelane, at a concentration of 10−6 M, was without effect on the subcellular distribution of [3H]phorbol 12,13-dibutyrate binding activity in the CA1 region. These observations suggest that bifemelane acts directly on the hippocampus to induce translocation of protein kinase C in the CA3 region. Such an effect may be associated with the bifemelane-induced augmentation of the long-term potentiation in this region of the brain.Key words: bifemelane, protein kinase C, hippocampal slice, translocation, CA3.

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