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Contribution of protein kinase Cα in the stimulation of insulin by the down-regulation of Cavβ subunits

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Abstract

Voltage-gated calcium (Cav) channels and protein kinase C (PKC) isozymes are involved in insulin secretion. In addition, Cavβ, one of the auxiliary subunits of Cav channels, also regulates the secretion of insulin as knockout of Cavβ3 (β3−/−) subunits in mice led to efficient glucose homeostasis and increased insulin levels. We examined whether other types of Cavβ subunits also have similar properties. In this regard, we used small interfering RNA (siRNA) of these subunits (20 μg each) to down-regulate them and examined blood glucose, serum insulin and PKC translocation in isolated pancreatic β cells of mice. While the down-regulation of Cavβ2 and β3 subunits increased serum insulin levels and caused efficient glucose homeostasis, the down-regulation of Cavβ1 and β4 subunits failed to affect both these parameters. Examination of PKC isozymes in the pancreatic β-cells of Cavβ2- or β3 siRNA-injected mice showed that three PKC isozymes, viz., PKC α, βII and θ, translocated to the membrane. This suggests that when present, Cavβ2 and β3 subunits inhibited PKC activation. Among these three isozymes, only PKCα siRNA inhibited insulin and increased glucose concentrations. It is possible that the activation of PKCs βII and θ is not sufficient for the release of insulin and PKCα is the mediator of insulin secretion under the control of Cavβ subunits. Since Cavβ subunits are present intracellularly, it is possible that they (1) inhibited the translocation of PKC isozymes to the membrane and (2) decreased the interaction between Cav channels and PKC isozymes and thus the secretion of insulin.

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References

  1. F.M. Ashcroft, P. Rorsman, Electrophysiology of the pancreatic β-cells. Prog. Biophys. Mol. Biol. 54, 87–143 (1989)

    Article  PubMed  CAS  Google Scholar 

  2. S. Straub, G. Sharp, Glucose-stimulated signaling pathways in biphasic insulin secretion. Diabetes Metab. Res. 18, 451–463 (2002)

    Article  CAS  Google Scholar 

  3. S.-N. Yang, P.-O. Berggren, Cav2.3 channels and PKC lambda: new players in insulin secretion. J. Clin. Invest. 115, 16–20 (2005)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  4. S. Yang, P.-O. Berggren, β-cell Cav channel regulation in physiology and pathophysiology. Am. J. Physiol.-Endocrinol. Metab. 288, E16–E28 (2005)

    Article  PubMed  CAS  Google Scholar 

  5. M. Yedovitzky, D. Mochly-Rosen, J. Johnson, M. Gray, D. Ron, E. Abramovitch, E. Cerasi, R. Nesher, Translocation inhibitors define specificity of protein kinase C isozymes in pancreatic β-cells. J. Biol. Chem. 272, 1417–1420 (1997)

    Article  PubMed  CAS  Google Scholar 

  6. N. Hashimoto, Y. Kido, T. Uchida, T. Matsuda, K. Suzuki, H. Inoue, M. Matsumoto, W. Ogawa, S. Maeda, H. Fujihara, Y. Ueta, Y. Uchiyama, K. Akimoto, S. Ohno, T. Noda, M. Kasuga, PKCλ regulates glucose-induced insulin secretion through modulation of gene expression in pancreatic β cells. J. Clin. Invest. 115, 138–145 (2005)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  7. A. Newton, Diacylglycerol’s affair with protein kinase C turns 25. Trends Pharmacol. Sci. 25, 175–177 (2004)

    Article  PubMed  CAS  Google Scholar 

  8. K. Knutson, M. Hoenig, Identification and subcellular characterization of protein kinase-C isoforms in insulinoma beta-cells and whole islets. Endocrinology 135, 881–886 (1994)

    PubMed  CAS  Google Scholar 

  9. Q.-F. Wan, Y. Dong, H. Yang, X. Lou, J. Ding, T. Xu, Protein kinase activation increases insulin secretion by sensitizing the secretory machinery to Ca2+. J. Gen. Physiol. 124, 653–662 (2004)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  10. H. Zhang, M. Nagasawa, S. Yamada, H. Mogami, Y. Suzuki, I. Kojima, Bimodal role of conventional protein kinase C in insulin secretion from rat pancreatic β-cells. J. Physiol. (Lond.) 561, 133–147 (2004)

    Article  CAS  Google Scholar 

  11. P. Pinton, T. Tsuboi, E. Ainscow, T. Pozzan, R. Rizzuto, G. Rutter, Dynamics of glucose-induced membrane recruitment of protein kinase C βII in living pancreatic islet β-cells. J. Biol. Chem. 277, 37702–37710 (2002)

    Article  PubMed  CAS  Google Scholar 

  12. A.C. Dolphin, Calcium channel diversity: multiple roles of calcium channel subunits. Curr. Opin. Neurobiol. 19(3), 237–244 (2009)

    Article  PubMed  CAS  Google Scholar 

  13. W.A. Catterall, Signaling complexes of voltage-gated sodium and calcium channels. Neurosci. Lett. 486(2), 107–116 (2010)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  14. A. Davalli, E. Biancardi, A. Pollo, C. Socci, A. Pontiroli, G. Pozza, F. Clementi, E. Sher, E. Carbone, Dihydropyridine-sensitive and -insensitive voltage-operated calcium channels participate in the control of glucose-induced insulin release from human pancreatic β cells. J. Endocrinol. 150, 195–203 (1996)

    Article  PubMed  CAS  Google Scholar 

  15. B. Ligon, A. Boyd, K. Dunlap, Class A calcium channel variants in pancreatic islets and their role in insulin secretion. J. Biol. Chem. 273, 13905–13911 (1998)

    Article  PubMed  CAS  Google Scholar 

  16. E. Sher, F. Giovannini, A. Codignola, M. Passafaro, P. Giorgi-Rossi, S. Volsen, P. Craig, A. Davalli, P. Carrera, Voltage-operated calcium channel heterogeneity in pancreatic β cells: physiopathological implications. J. Bioenergy Biomembr. 35, 687–696 (2003)

    Article  CAS  Google Scholar 

  17. V. Schulla, E. Renstrom, R. Feil, S. Feil, I. Franklin, A. Gjinovci, X. Jing, D. Laux, I. Lundquist, M. Magnuson, S. Obermuller, C. Olofsson, A. Salehi, A. Wendt, N. Klugbauer, C. Wollheim, P. Rorsman, F. Hofmann, Impaired insulin secretion and glucose tolerance in beta cell-selective Cav1.2 Ca2+ channel null mice. EMBO J. 22, 3844–3854 (2003)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  18. X. Jing, D.-Q. Li, C. Olofsson, A. Salehi, V. Surve, J. Caballero, R. Ivarsson, I. Lundquist, A. Pereverzev, T. Schneider, P. Rorsman, E. Renström, CaV2.3 calcium channels control second-phase insulin release. J. Clin. Invest. 115, 146–154 (2005)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  19. Y.L. Muller, R. Hanson, C. Zimmermann, I. Harper, J. Sutherland, S. Kobes, International type 2 diabetes 1q consortium, W. Knowler, C. Bogardus, L. Baier, variants in the Cav2.3 (α1E) subunit of voltage-activated Ca2+ channels are associated with insulin resistance and type 2 diabetes in Pima Indians. Diabetes 56, 3089–3094 (2007)

    Article  PubMed  CAS  Google Scholar 

  20. M. Komatsu, T. Schermerhorn, T. Aizawa, G. Sharp, Glucose stimulation of insulin release in the absence of extracellular Ca2+ and in the absence of any rise in intracellular Ca2+ in rat pancreatic islets. Proc. Natl. Acad. Sci. USA 92, 10728–10732 (1995)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  21. M. Komatsu, T. Schermerhorn, S. Straub, G. Sharp, Pituitary adenylate cyclase-activating peptide, carbachol, and glucose stimulate insulin release in the absence of an increase in intracellular Ca2+. Mol. Pharmacol. 50, 1047–1054 (1996)

    PubMed  CAS  Google Scholar 

  22. I.-S. Lee, E.-M. Hur, B.-C. Suh, M.-H. Kim, D.-S. Koh, I.-J. Rhee, H. Ha, K.-T. Kim, Protein kinase A- and C-induced insulin release from Ca2+-insensitive pools. Cell. Signal. 15, 529–537 (2003)

    Article  PubMed  CAS  Google Scholar 

  23. D. McHugh, E. Sharp, T. Scheuer, W.A. Catterall, Inhibition of cardiac l-type calcium channels by protein kinase C phosphorylation of two sites in the N-terminal domain. Proc. Natl. Acad. Sci. USA 97, 12334–12338 (2000)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  24. G.L. Kamatchi, R. Franke, C. Lynch III, J.J. Sando, Identification of Sites responsible for potentiation of type 2.3 calcium currents by acetyl-β-methylcholine. J. Biol. Chem. 279(6), 4102–4109 (2004)

    Article  PubMed  CAS  Google Scholar 

  25. H. Fang, R. Franke, S. Patanavanich, A. Lalvani, N. Powell, J.J. Sando, G.L. Kamatchi, Role of α1 2.3 subunit I–II linker sites in the enhancement of Cav 2.3 currents by phorbol 13-myristate 13-acetate. J. Biol. Chem. 280, 23559–23565 (2005)

    Article  PubMed  CAS  Google Scholar 

  26. H. Fang, S. Patanavanich, S. Rajagopal, X. Yi, M. Gill, J.J. Sando, G.L. Kamatchi, Inhibitory role of Ser-425 of the α12.2 subunit in the enhancement of Cav2.2 currents by phorbol-12-myristate, 13-acetate. J. Biol. Chem. 281, 20011–20017 (2006)

    Article  PubMed  CAS  Google Scholar 

  27. S. Rajagopal, H. Fang, C. Oronce, S. Jhaveri, S. Taneja, E. Dehlin, S. Snyder, J.J. Sando, G.L. Kamatchi, Site-specific regulation of CA(V)2.2 channels by protein kinase C isozymes betaII and epsilon. Neuroscience 159, 618–628 (2009)

    Article  PubMed  CAS  Google Scholar 

  28. S. Rajagopal, H. Fang, C. Lynch III, J.J. Sando, G.L. Kamatchi, Effects of isoflurane on the expressed Cav2.2 currents in Xenopus oocytes depend on the activation of protein kinase C δ and its phosphorylation sites in the Cav2.2α1 subunits. Neuroscience 182, 232–240 (2011)

    Article  PubMed  CAS  Google Scholar 

  29. P.-O. Berggren, S.-N. Yang, M. Murakami, A. Efanov, S. Uhles, M. Kohler, T. Moede, A. Fernstrom, I. Appelskog, C. Aspinwall, S. Zaitsev, O. Larsson, L. de Vargas, C. Fecher-Trost, P. Weibgerber, A. Ludwig, B. Leibiger, L. Juntti-Berggren, C. Barker, J. Gromada, M. Freichel, I. Leibiger, V. Flockerzi, Removal of Ca2+ channel β3 subunit enhances Ca2+ oscillation frequency and insulin exocytosis. Cell 119, 273–284 (2004)

    Article  PubMed  CAS  Google Scholar 

  30. B. Gao, Y. Sekido, A. Maximov, M. Saad, E. Forgacs, F. Latif, M. Wei, M. Lerman, J. Lee, E. Perez-Reyes, I. Bezprozvanny, J. Minna, Functional properties of a new voltage-dependent calcium channel α2/δ auxiliary subunit gene (CACNA2D2). J. Biol. Chem. 275, 12237–12242 (2000)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  31. Y. Iwashima, A. Abiko, F. Ushikubi, A. Hata, K. Kaku, H. Sano, M. Eto, Downregulation of the voltage-dependent calcium channel (VDCC) β-subunit mRNAs in pancreatic islets of type 2 diabetic rats. Biochem. Biophys. Res. Commun. 280, 923–932 (2001)

    Article  PubMed  CAS  Google Scholar 

  32. D. Mears, Regulation of insulin secretion in islets of langerhans by Ca2+ channels. J. Membr. Biol. 200, 57–66 (2004)

    Article  PubMed  CAS  Google Scholar 

  33. A. Newton, Protein kinase C: poised to signal. Am. J. Physiol-Endocrinol. Metab. 298, E395–E402 (2010)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  34. D. Jeffrey, S. Dula, K. Corbin, R. Wu, C. Nunemaker, A practical guide to rodent islet isolation and assessment. Biol. Proced. Online 11, 3–31 (2009)

    Article  Google Scholar 

  35. G. Zhang, V. Budker, J. Wolff, High levels of foreign gene expression in hepatocytes after tail vein injections of naked plasmid DNA. Hum. Gene Ther. 10, 1735–1737 (1999)

    Article  PubMed  CAS  Google Scholar 

  36. F. Liu, Y. Song, D. Liu, Hydrodynamics-based transfection in animals by systemic administration of plasmid DNA. Gene Ther. 6, 1258–1266 (1999)

    Article  PubMed  CAS  Google Scholar 

  37. D. Lewis, J. Hagstrom, A. Loomis, J. Wolff, H. Herweijer, Efficient delivery of siRNA for inhibition of gene expression in postnatal mice. Nat. Genet. 32, 107–108 (2002)

    Article  PubMed  CAS  Google Scholar 

  38. E. Song, S.-K. Lee, J. Wang, N. Ince, N. Ouyang, J. Min, J. Chen, P. Shankar, J. Lieberman, RNA interference targeting Fas protects mice from fulminant hepatitis. Nat. Med. 9, 347–351 (2003)

    Article  PubMed  CAS  Google Scholar 

  39. P. Hamar, E. Song, G. Kokeny, A. Chen, N. Ouyang, J. Lieberman, Small interfering RNA targeting Fas protects mice against renal ischemia-reperfusion injury. Proc. Natl. Acad. Sci. USA 101, 14883–14888 (2004)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  40. S.-N. Yang, P.-O. Berggren, The role of voltage-gated calcium channels in pancreatic beta-cell physiology and pathophysiology. Endocr. Rev. 27, 621–676 (2006)

    Article  PubMed  CAS  Google Scholar 

  41. A. Pereverzev, R. Vajna, G. Pfitzer, J. Hescheler, U. Klockner, T. Schneider, Reduction of insulin secretion in the insulinoma cell line INS-1 by overexpression of a Cav2.3 (α1E) calcium channel antisense cassette. Eur. J. Endocrinol. 146, 881–889 (2002)

    Article  PubMed  CAS  Google Scholar 

  42. T. Shiraiwa, M. Kashiwayanagi, T. Iijima, M. Murakami, Involvement of calcium channel β3 subunit in olfactory signal transduction. Biochem. Biophys. Res. Commun. 355, 1019–1024 (2007)

    Article  PubMed  CAS  Google Scholar 

  43. P. Gilon, J. Henquin, Mechanisms and physiological significance of the cholinergic control of pancreatic β-cell function. Endocr. Rev. 22, 565–604 (2001)

    PubMed  CAS  Google Scholar 

  44. D. Gautam, S. Han, F. Hamdan, J. Jeon, B. Li, J. Li, Y. Cui, D. Mears, H. Lu, C. Deng, T. Heard, J. Wess, A critical role for beta cell M3 muscarinic acetylcholine receptors in regulating insulin release and blood glucose homeostasis in vivo. Cell Metab. 3, 449–461 (2006)

    Article  PubMed  CAS  Google Scholar 

  45. S. Rajagopal, H. Fang, S. Patanavanich, J.J. Sando, G.L. Kamatchi, Protein kinase C isozyme-specific potentiation of expressed Cav2.3 currents by acetyl-β-methylcholine and phorbol-12-myristate, 13-acetate. Brain Res. 1210, 1–10 (2008)

    Article  PubMed  CAS  PubMed Central  Google Scholar 

  46. J.W. Hell, R.E. Westenbroek, C. Warner, M.K. Ahlijanian, W. Prystay, M.M. Gilbert, T.P. Snutch, W.A. Catterall, Identification and differential subcellular localization of the neuronal class C and class D l-type calcium channel α1 subunits. J. Cell Biol. 123, 949–962 (1993)

    Article  PubMed  CAS  Google Scholar 

  47. C.T. Yokoyama, R.E. Westenbroek, J.W. Hell, T.W. Soong, T.P. Snutch, W.A. Catterall, Biochemical properties and subcellular distribution of the neuronal class E calcium channel α1 subunit. J. Neurosci. 15, 6419–6432 (1995)

    PubMed  CAS  Google Scholar 

  48. A. Stea, T.W. Soong, T.P. Snutch, Determinants of PKC-dependent modulation of a family of neuronal calcium channels. Neuron 15, 929–940 (1995)

    Article  PubMed  CAS  Google Scholar 

  49. G.L. Kamatchi, S. Tiwari, C. Chan, D. Chen, S.-H. Do, M. Durieux, C. Lynch III, Distinct regulation of expressed calcium channel 2.3 in Xenopus oocytes by direct or indirect activation of protein kinase C. Brain Res. 968, 227–237 (2003)

    Article  PubMed  CAS  Google Scholar 

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Acknowledgments

This work was supported by National Institutes of General Medical Sciences (SCORE3, GM096947) to G.L.K. The project described was supported in part by Grant Number G11HD052382 from the National Institute of Child Health and Human Development. The content is solely the responsibility of the authors and does not necessarily represent the views of the National Institute of Child Health and Human Development or the National Institutes of Health.

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The authors fully declare any financial or other potential conflict of interest.

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Correspondence to Ganesan L. Kamatchi.

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Rajagopal, S., Fields, B.L. & Kamatchi, G.L. Contribution of protein kinase Cα in the stimulation of insulin by the down-regulation of Cavβ subunits. Endocrine 47, 463–471 (2014). https://doi.org/10.1007/s12020-013-0149-y

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