Evidence for a role of protein kinase C zeta subspecies in maturation of Xenopus laevis oocytes.

A number of studies have demonstrated the activation of phospholipase C-mediated hydrolysis of phosphatidylcholine (PC-PLC) both by growth factors and by the product of the ras oncogene, p21ras. Evidence has been presented indicating that the stimulation of this phospholipid degradative pathway is sufficient to activate mitogenesis in fibroblasts as well as that it is sufficient and necessary for induction of maturation in Xenopus laevis oocytes. However, the mechanism whereby PC-PLC transduces mitogenic signals triggered by growth factors or oncogenes remains to be elucidated. In this study, data are presented that show the involvement of protein kinase C zeta subspecies in the channelling of the mitogenic signal activated by insulin-p21ras-PC-PLC in Xenopus oocytes as well as the lack of a critical role of protein kinase C isotypes alpha, beta, gamma, delta, and epsilon in these pathways.

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Inhibition of protein kinase C zeta subspecies blocks the activation of an NF-kappa B-like activity in Xenopus laevis oocytes

Molecular and Cellular Biology ◽

10.1128/mcb.13.2.1290-1295.1993 ◽

1993 ◽

Vol 13 (2) ◽

pp. 1290-1295

Author(s):

I Dominguez ◽

L Sanz ◽

F Arenzana-Seisdedos ◽

M T Diaz-Meco ◽

J L Virelizier ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Xenopus Laevis ◽

Critical Role ◽

Xenopus Laevis Oocytes ◽

Nuclear Factor ◽

Nf Kappa B ◽

Kinase C ◽

Ras P21 ◽

Protein Kinase C Zeta

Nuclear factor kappa B (NF-kappa B) plays a critical role in the regulation of a large variety of cellular genes. However, the mechanism whereby this nuclear factor is activated remains to be determined. In this report, we present evidence that in oocytes from Xenopus laevis, (i) ras p21- and phospholipase C (PLC)-mediated phosphatidylcholine (PC) hydrolysis activates NF-kappa B and (ii) protein kinase C zeta subspecies is involved in the activation of NF-kappa B in response to insulin/ras p21/PC-PLC. Thus, the microinjection of either ras p21 or PC-PLC, or the exposure of oocytes to insulin, promotes a significant translocation to the nucleus of an NF-kappa B-like activity. This effect is not observed when oocytes are incubated with phorbol myristate acetate or progesterone, both of which utilize a ras p21-independent pathway for oocyte activation. These data strongly suggest a critical role of the insulin/ras p21/PC-PLC/protein kinase C zeta pathway in the control of NF-kappa B activation.

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Inhibition of protein kinase C zeta subspecies blocks the activation of an NF-kappa B-like activity in Xenopus laevis oocytes.

Molecular and Cellular Biology ◽

10.1128/mcb.13.2.1290 ◽

1993 ◽

Vol 13 (2) ◽

pp. 1290-1295 ◽

Cited By ~ 94

Author(s):

I Dominguez ◽

L Sanz ◽

F Arenzana-Seisdedos ◽

M T Diaz-Meco ◽

J L Virelizier ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Xenopus Laevis ◽

Critical Role ◽

Xenopus Laevis Oocytes ◽

Nuclear Factor ◽

Nf Kappa B ◽

Kinase C ◽

Ras P21 ◽

Protein Kinase C Zeta

Nuclear factor kappa B (NF-kappa B) plays a critical role in the regulation of a large variety of cellular genes. However, the mechanism whereby this nuclear factor is activated remains to be determined. In this report, we present evidence that in oocytes from Xenopus laevis, (i) ras p21- and phospholipase C (PLC)-mediated phosphatidylcholine (PC) hydrolysis activates NF-kappa B and (ii) protein kinase C zeta subspecies is involved in the activation of NF-kappa B in response to insulin/ras p21/PC-PLC. Thus, the microinjection of either ras p21 or PC-PLC, or the exposure of oocytes to insulin, promotes a significant translocation to the nucleus of an NF-kappa B-like activity. This effect is not observed when oocytes are incubated with phorbol myristate acetate or progesterone, both of which utilize a ras p21-independent pathway for oocyte activation. These data strongly suggest a critical role of the insulin/ras p21/PC-PLC/protein kinase C zeta pathway in the control of NF-kappa B activation.

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Local anaesthetics inhibit signalling of human NMDA receptors recombinantly expressed in Xenopus laevis oocytes: role of protein kinase C

British Journal of Anaesthesia ◽

10.1093/bja/aei271 ◽

2006 ◽

Vol 96 (1) ◽

pp. 77-87 ◽

Cited By ~ 62

Author(s):

K Hahnenkamp ◽

M.E. Durieux ◽

A Hahnenkamp ◽

S.K. Schauerte ◽

C.W. Hoenemann ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Xenopus Laevis ◽

Nmda Receptors ◽

Local Anaesthetics ◽

Xenopus Laevis Oocytes ◽

Kinase C

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Protein kinase C and chemical-induced abnormal palate development

Human & Experimental Toxicology ◽

10.1191/0960327105ht515oa ◽

2005 ◽

Vol 24 (4) ◽

pp. 203-214 ◽

Cited By ~ 3

Author(s):

Chada S Reddy

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Single Gene ◽

Critical Role ◽

Early Death ◽

Palate Development ◽

Kinase C ◽

A Cell ◽

Context Specific

The protein kinase C (PKC) family of proteins mediates the action of growth factors and other ligands by activating a network of transcription factors that bind to TRE sequences in the promoters of many genes that regulate cell proliferation, differentiation, extracellular matrix synthesis, apoptosis and others in a cell type-, isozymeand context-specific manner. The critical role of PKC in embryonic development is indicated by early death of embryos in which one or more of these isozymes are inactivated. Our studies together with others show that palatal PKC signalling is functional and may be essential for normal palate development. Although single gene knockouts have failed to exhibit the cleft palate (CP) phenotype, owing to compensation by other kinases, many chemicals including the mycotoxin, secalonic acid D, disrupt palatal PKC signalling leading to altered palatal mesenchymal gene expression. The potential relevance of such effects to chemical-induced CP is discussed.

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Growth factors protect against intestinal epithelial barrier hyperpermeability by stabilizing microtubules: Role of protein kinase C (PKC) signal activation & Ca2+ homeostasis

Gastroenterology ◽

10.1016/s0016-5085(00)83842-1 ◽

2000 ◽

Vol 118 (4) ◽

pp. A432 ◽

Cited By ~ 1

Author(s):

Ali Banan ◽

Sandeep Choudhary ◽

Yang Zhang ◽

Ali Keshavarzian

Keyword(s):

Protein Kinase C ◽

Growth Factors ◽

Protein Kinase ◽

Epithelial Barrier ◽

Intestinal Epithelial ◽

Intestinal Epithelial Barrier ◽

Kinase C ◽

Signal Activation

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Influence of Protein Kinase C and Calcium in the Course of Thrombin Receptors Activation.

Blood ◽

10.1182/blood.v110.11.3194.3194 ◽

2007 ◽

Vol 110 (11) ◽

pp. 3194-3194

Author(s):

Ying Xie ◽

Yue Han ◽

De Pei Wu ◽

Aining Sun ◽

Wei Zhang

Keyword(s):

Protein Kinase C ◽

Platelet Aggregation ◽

Protein Kinase ◽

Membrane Surface ◽

Signal Transmission ◽

Critical Role ◽

Signal Pathways ◽

Kinase C ◽

Thrombin Receptors

Abstract Object In order to compare the functions of protein kinase C (PKC) and calcium (Ca2+) in platelet aggregation and platelet membrane surface glycoproteins GPIb expression after thrombin receptors activation, then to investigate the role of Gq signal transmission pathway in the course of thrombin receptors activation. Methods Peptide SFLLRN (PAR1-AP) and AYPGKF (PAR4-AP) were used for stimulating platelet at different time point (0, 1, 2, 5, 10, 30min), then the alterations of platelet aggregation and GPIb were analyzed in the involvement of Ro-31-2220 (inhibitor of PKC) and BAPTA/AM (calcium chelator). Results Either PAR1 or PAR4 peptide can induce absolute platelet aggregation, together with a reversible internalization of GPIb. Platelet aggregation was inhibited by Ro-31-2220 or BAPTA/AM while the shape change curve still occurred upon PARs activation. In addition, Ro-31-2220 decreases GPIb centralisation upon PAR1 stimulation (P <0.05 at 1, 2 min), though it blocks the pool of GPIb inside platelet in PAR4 activation (P <0.05 at 10, 30 min). Meanwhile, GPIb internalization was blocked by BAPTA for both peptides (P <0.05 at 1∼10 min). Conclusion All the results confirm a critical role of Gq pathway in thrombin signal transmission through the involvement of protein kinase C and calcium. Calcium is closely correlated with the thrombin receptors activation, seemed to be similar for two PARs signal pathways. Protein kinase C urges GPIb centralisation in PAR1 pathway and accelerates GPIbα return in PAR4 pathway.

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