Abstract
Hydrolysis of inositol phospholipids by receptor stimulation activates two separate signaling pathways, one leading to the activation of protein kinase C (C kinase) via formation of diacylglycerol. The other is the inositol trisphosphate (IP3)/Ca2+ pathway and a major downstream kinase which is activated is Ca2+/calmodulin-dependent protein kinase II (CaM kinase II). To examine signaling pathways of C kinase and CaM kinase II to the cytoskeletal protein vimentin, we prepared monoclonal antibodies YT33 and MO82 which recognize the phosphorylation state of vimentin by C kinase and by CaM kinase II, respectively. Ectopic expression of constitutively active C kinase or CaM kinase II in primary cultured astrocytes by microinjection of the corresponding expression vectors induced phosphorylation of vimentin at each specific phosphorylation site, followed by reorganization of vimentin filament networks. In contrast, simultaneous activation of C kinase and CaM kinase II by inositol phospholipid hydrolysis with receptor stimulation led to an exclusive phosphorylation of vimentin at the CaM kinase II site, not at the site of C kinase. These results indicate that the intracellular targeting of C kinase and CaM kinase II signalings to vimentin is regulated separately, under physiological conditions.
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- Ando S., Tanabe K., Gonda Y., Sato C., Inagaki M. Domain- and sequence-specific phosphorylation of vimentin induces disassembly of the filament structure. Biochemistry. 1989 Apr 4;28(7):2974–2979. doi: 10.1021/bi00433a035. [DOI] [PubMed] [Google Scholar]
- Ando S., Tokui T., Yamauchi T., Sugiura H., Tanabe K., Inagaki M. Evidence that Ser-82 is a unique phosphorylation site on vimentin for Ca2(+)-calmodulin-dependent protein kinase II. Biochem Biophys Res Commun. 1991 Mar 29;175(3):955–962. doi: 10.1016/0006-291x(91)91658-y. [DOI] [PubMed] [Google Scholar]
- Azzi A., Boscoboinik D., Hensey C. The protein kinase C family. Eur J Biochem. 1992 Sep 15;208(3):547–557. doi: 10.1111/j.1432-1033.1992.tb17219.x. [DOI] [PubMed] [Google Scholar]
- Berridge M. J. Inositol trisphosphate and calcium signalling. Nature. 1993 Jan 28;361(6410):315–325. doi: 10.1038/361315a0. [DOI] [PubMed] [Google Scholar]
- Bertrand F., Veissiere D., Hermelin B., Paul A., Capeau J., Picard J., Cherqui G. Phosphorylation of vimentin is an intermediate step in protein kinase C-mediated glycoconjugate secretion. Am J Physiol. 1994 Mar;266(3 Pt 1):C611–C621. doi: 10.1152/ajpcell.1994.266.3.C611. [DOI] [PubMed] [Google Scholar]
- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
- Browning E. T., Sanders M. M. Vimentin: a phosphoprotein under hormonal regulation. J Cell Biol. 1981 Sep;90(3):803–808. doi: 10.1083/jcb.90.3.803. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chida K., Hashiba H., Sasaki K., Kuroki T. Activation of protein kinase C and specific phosphorylation of a Mr 90,000 membrane protein of promotable BALB/3T3 and C3H/10T1/2 cells by tumor promoters. Cancer Res. 1986 Mar;46(3):1055–1062. [PubMed] [Google Scholar]
- Chou Y. H., Bischoff J. R., Beach D., Goldman R. D. Intermediate filament reorganization during mitosis is mediated by p34cdc2 phosphorylation of vimentin. Cell. 1990 Sep 21;62(6):1063–1071. doi: 10.1016/0092-8674(90)90384-q. [DOI] [PubMed] [Google Scholar]
- Chou Y. H., Ngai K. L., Goldman R. The regulation of intermediate filament reorganization in mitosis. p34cdc2 phosphorylates vimentin at a unique N-terminal site. J Biol Chem. 1991 Apr 25;266(12):7325–7328. [PubMed] [Google Scholar]
- Ciesielski-Treska J., Ulrich G., Aunis D. Protein kinase C-induced redistribution of the cytoskeleton and phosphorylation of vimentin in cultured brain macrophages. J Neurosci Res. 1991 Jul;29(3):362–378. doi: 10.1002/jnr.490290312. [DOI] [PubMed] [Google Scholar]
- Coca-Prados M. Regulation of protein phosphorylation of the intermediate-sized filament vimentin in the ciliary epithelium of the mammalian eye. J Biol Chem. 1985 Aug 25;260(18):10332–10338. [PubMed] [Google Scholar]
- Colbran R. J., Schworer C. M., Hashimoto Y., Fong Y. L., Rich D. P., Smith M. K., Soderling T. R. Calcium/calmodulin-dependent protein kinase II. Biochem J. 1989 Mar 1;258(2):313–325. doi: 10.1042/bj2580313. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Czernik A. J., Girault J. A., Nairn A. C., Chen J., Snyder G., Kebabian J., Greengard P. Production of phosphorylation state-specific antibodies. Methods Enzymol. 1991;201:264–283. doi: 10.1016/0076-6879(91)01025-w. [DOI] [PubMed] [Google Scholar]
- Deery W. J. Role of phosphorylation in keratin and vimentin filament integrity in cultured thyroid epithelial cells. Cell Motil Cytoskeleton. 1993;26(4):325–339. doi: 10.1002/cm.970260407. [DOI] [PubMed] [Google Scholar]
- Eriksson J. E., Brautigan D. L., Vallee R., Olmsted J., Fujiki H., Goldman R. D. Cytoskeletal integrity in interphase cells requires protein phosphatase activity. Proc Natl Acad Sci U S A. 1992 Nov 15;89(22):11093–11097. doi: 10.1073/pnas.89.22.11093. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Evans R. M. Cyclic AMP-dependent protein kinase-induced vimentin filament disassembly involves modification of the N-terminal domain of intermediate filament subunits. FEBS Lett. 1988 Jul 4;234(1):73–78. doi: 10.1016/0014-5793(88)81306-1. [DOI] [PubMed] [Google Scholar]
- Fackler M. J., Civin C. I., Sutherland D. R., Baker M. A., May W. S. Activated protein kinase C directly phosphorylates the CD34 antigen on hematopoietic cells. J Biol Chem. 1990 Jul 5;265(19):11056–11061. [PubMed] [Google Scholar]
- Franke W. W., Schmid E., Grund C., Geiger B. Intermediate filament proteins in nonfilamentous structures: transient disintegration and inclusion of subunit proteins in granular aggregates. Cell. 1982 Aug;30(1):103–113. doi: 10.1016/0092-8674(82)90016-2. [DOI] [PubMed] [Google Scholar]
- Gard D. L., Lazarides E. Analysis of desmin and vimentin phosphopeptides in cultured avian myogenic cells and their modulation by 8-bromo-adenosine 3',5'-cyclic monophosphate. Proc Natl Acad Sci U S A. 1982 Nov;79(22):6912–6916. doi: 10.1073/pnas.79.22.6912. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geisler N., Hatzfeld M., Weber K. Phosphorylation in vitro of vimentin by protein kinases A and C is restricted to the head domain. Identification of the phosphoserine sites and their influence on filament formation. Eur J Biochem. 1989 Aug 1;183(2):441–447. doi: 10.1111/j.1432-1033.1989.tb14947.x. [DOI] [PubMed] [Google Scholar]
- Geisler N., Weber K. Phosphorylation of desmin in vitro inhibits formation of intermediate filaments; identification of three kinase A sites in the aminoterminal head domain. EMBO J. 1988 Jan;7(1):15–20. doi: 10.1002/j.1460-2075.1988.tb02778.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gonda Y., Nishizawa K., Ando S., Kitamura S., Minoura Y., Nishi Y., Inagaki M. Involvement of protein kinase C in the regulation of assembly-disassembly of neurofilaments in vitro. Biochem Biophys Res Commun. 1990 Mar 30;167(3):1316–1325. doi: 10.1016/0006-291x(90)90667-c. [DOI] [PubMed] [Google Scholar]
- Goshima Y., Ohsako S., Yamauchi T. Overexpression of Ca2+/calmodulin-dependent protein kinase II in Neuro2a and NG108-15 neuroblastoma cell lines promotes neurite outgrowth and growth cone motility. J Neurosci. 1993 Feb;13(2):559–567. doi: 10.1523/JNEUROSCI.13-02-00559.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Griffith L. C., Schulman H. The multifunctional Ca2+/calmodulin-dependent protein kinase mediates Ca2+-dependent phosphorylation of tyrosine hydroxylase. J Biol Chem. 1988 Jul 5;263(19):9542–9549. [PubMed] [Google Scholar]
- Hanson P. I., Schulman H. Neuronal Ca2+/calmodulin-dependent protein kinases. Annu Rev Biochem. 1992;61:559–601. doi: 10.1146/annurev.bi.61.070192.003015. [DOI] [PubMed] [Google Scholar]
- Harrison B. C., Mobley P. L. Phorbol myristate acetate and 8-bromo-cyclic AMP-induced phosphorylation of glial fibrillary acidic protein and vimentin in astrocytes: comparison of phosphorylation sites. J Neurochem. 1991 May;56(5):1723–1730. doi: 10.1111/j.1471-4159.1991.tb02073.x. [DOI] [PubMed] [Google Scholar]
- Hirai S., Izumi Y., Higa K., Kaibuchi K., Mizuno K., Osada S., Suzuki K., Ohno S. Ras-dependent signal transduction is indispensable but not sufficient for the activation of AP1/Jun by PKC delta. EMBO J. 1994 May 15;13(10):2331–2340. doi: 10.1002/j.1460-2075.1994.tb06517.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huang C. K., Devanney J. F., Kennedy S. P. Vimentin, a cytoskeletal substrate of protein kinase C. Biochem Biophys Res Commun. 1988 Feb 15;150(3):1006–1011. doi: 10.1016/0006-291x(88)90728-0. [DOI] [PubMed] [Google Scholar]
- Inagaki M., Gonda Y., Matsuyama M., Nishizawa K., Nishi Y., Sato C. Intermediate filament reconstitution in vitro. The role of phosphorylation on the assembly-disassembly of desmin. J Biol Chem. 1988 Apr 25;263(12):5970–5978. [PubMed] [Google Scholar]
- Inagaki M., Gonda Y., Nishizawa K., Kitamura S., Sato C., Ando S., Tanabe K., Kikuchi K., Tsuiki S., Nishi Y. Phosphorylation sites linked to glial filament disassembly in vitro locate in a non-alpha-helical head domain. J Biol Chem. 1990 Mar 15;265(8):4722–4729. [PubMed] [Google Scholar]
- Inagaki M., Nakamura Y., Takeda M., Nishimura T., Inagaki N. Glial fibrillary acidic protein: dynamic property and regulation by phosphorylation. Brain Pathol. 1994 Jul;4(3):239–243. doi: 10.1111/j.1750-3639.1994.tb00839.x. [DOI] [PubMed] [Google Scholar]
- Inagaki M., Nishi Y., Nishizawa K., Matsuyama M., Sato C. Site-specific phosphorylation induces disassembly of vimentin filaments in vitro. Nature. 1987 Aug 13;328(6131):649–652. doi: 10.1038/328649a0. [DOI] [PubMed] [Google Scholar]
- Inagaki M., Watanabe M., Hidaka H. N-(2-Aminoethyl)-5-isoquinolinesulfonamide, a newly synthesized protein kinase inhibitor, functions as a ligand in affinity chromatography. Purification of Ca2+-activated, phospholipid-dependent and other protein kinases. J Biol Chem. 1985 Mar 10;260(5):2922–2925. [PubMed] [Google Scholar]
- Inagaki N., Fukui H., Ito S., Yamatodani A., Wada H. Single type-2 astrocytes show multiple independent sites of Ca2+ signaling in response to histamine. Proc Natl Acad Sci U S A. 1991 May 15;88(10):4215–4219. doi: 10.1073/pnas.88.10.4215. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Inagaki N., Fukui H., Taguchi Y., Wang N. P., Yamatodani A., Wada H. Characterization of histamine H1-receptors on astrocytes in primary culture: [3H]mepyramine binding studies. Eur J Pharmacol. 1989 Nov 28;173(1):43–51. doi: 10.1016/0014-2999(89)90007-1. [DOI] [PubMed] [Google Scholar]
- Inagaki N., Ito M., Nakano T., Inagaki M. Spatiotemporal distribution of protein kinase and phosphatase activities. Trends Biochem Sci. 1994 Nov;19(11):448–452. doi: 10.1016/0968-0004(94)90128-7. [DOI] [PubMed] [Google Scholar]
- Inagaki N., Wada H. Histamine and prostanoid receptors on glial cells. Glia. 1994 Jun;11(2):102–109. doi: 10.1002/glia.440110205. [DOI] [PubMed] [Google Scholar]
- Ito S., Sugama K., Inagaki N., Fukui H., Giles H., Wada H., Hayaishi O. Type-1 and type-2 astrocytes are distinct targets for prostaglandins D2, E2, and F2 alpha. Glia. 1992;6(1):67–74. doi: 10.1002/glia.440060109. [DOI] [PubMed] [Google Scholar]
- Jefferson A. B., Schulman H. Phosphorylation of microtubule-associated protein-2 in GH3 cells. Regulation by cAMP and by calcium. J Biol Chem. 1991 Jan 5;266(1):346–354. [PubMed] [Google Scholar]
- Kasai H., Li Y. X., Miyashita Y. Subcellular distribution of Ca2+ release channels underlying Ca2+ waves and oscillations in exocrine pancreas. Cell. 1993 Aug 27;74(4):669–677. doi: 10.1016/0092-8674(93)90514-q. [DOI] [PubMed] [Google Scholar]
- Kitamura S., Ando S., Shibata M., Tanabe K., Sato C., Inagaki M. Protein kinase C phosphorylation of desmin at four serine residues within the non-alpha-helical head domain. J Biol Chem. 1989 Apr 5;264(10):5674–5678. [PubMed] [Google Scholar]
- Kitanaka J., Onoe H., Baba A. Astrocytes possess prostaglandin F2 alpha receptors coupled to phospholipase C. Biochem Biophys Res Commun. 1991 Aug 15;178(3):946–952. doi: 10.1016/0006-291x(91)90983-e. [DOI] [PubMed] [Google Scholar]
- Klymkowsky M. W., Bachant J. B., Domingo A. Functions of intermediate filaments. Cell Motil Cytoskeleton. 1989;14(3):309–331. doi: 10.1002/cm.970140302. [DOI] [PubMed] [Google Scholar]
- Kraft A. S., Anderson W. B. Phorbol esters increase the amount of Ca2+, phospholipid-dependent protein kinase associated with plasma membrane. Nature. 1983 Feb 17;301(5901):621–623. doi: 10.1038/301621a0. [DOI] [PubMed] [Google Scholar]
- Kusubata M., Tokui T., Matsuoka Y., Okumura E., Tachibana K., Hisanaga S., Kishimoto T., Yasuda H., Kamijo M., Ohba Y. p13suc1 suppresses the catalytic function of p34cdc2 kinase for intermediate filament proteins, in vitro. J Biol Chem. 1992 Oct 15;267(29):20937–20942. [PubMed] [Google Scholar]
- Lamb N. J., Fernandez A., Feramisco J. R., Welch W. J. Modulation of vimentin containing intermediate filament distribution and phosphorylation in living fibroblasts by the cAMP-dependent protein kinase. J Cell Biol. 1989 Jun;108(6):2409–2422. doi: 10.1083/jcb.108.6.2409. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Masliah E., Yoshida K., Shimohama S., Gage F. H., Saitoh T. Differential expression of protein kinase C isozymes in rat glial cell cultures. Brain Res. 1991 May 17;549(1):106–111. doi: 10.1016/0006-8993(91)90605-u. [DOI] [PubMed] [Google Scholar]
- Matsuoka Y., Nishizawa K., Yano T., Shibata M., Ando S., Takahashi T., Inagaki M. Two different protein kinases act on a different time schedule as glial filament kinases during mitosis. EMBO J. 1992 Aug;11(8):2895–2902. doi: 10.1002/j.1460-2075.1992.tb05358.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McCarthy K. D., Prime J., Harmon T., Pollenz R. Receptor-mediated phosphorylation of astroglial intermediate filament proteins in cultured astroglia. J Neurochem. 1985 Mar;44(3):723–730. doi: 10.1111/j.1471-4159.1985.tb12875.x. [DOI] [PubMed] [Google Scholar]
- Michell R. H. Inositol lipids in cellular signalling mechanisms. Trends Biochem Sci. 1992 Aug;17(8):274–276. doi: 10.1016/0968-0004(92)90433-a. [DOI] [PubMed] [Google Scholar]
- Mobley P. L., Combs D. L. Norepinephrine-mediated protein phosphorylation in astrocytes. Brain Res Bull. 1992 Sep-Oct;29(3-4):289–295. doi: 10.1016/0361-9230(92)90059-7. [DOI] [PubMed] [Google Scholar]
- Murti K. G., Kaur K., Goorha R. M. Protein kinase C associates with intermediate filaments and stress fibers. Exp Cell Res. 1992 Sep;202(1):36–44. doi: 10.1016/0014-4827(92)90401-s. [DOI] [PubMed] [Google Scholar]
- Neary J. T., Norenberg L. O., Norenberg M. D. Calcium-activated, phospholipid-dependent protein kinase and protein substrates in primary cultures of astrocytes. Brain Res. 1986 Oct 22;385(2):420–424. doi: 10.1016/0006-8993(86)91095-4. [DOI] [PubMed] [Google Scholar]
- Nishizawa K., Yano T., Shibata M., Ando S., Saga S., Takahashi T., Inagaki M. Specific localization of phosphointermediate filament protein in the constricted area of dividing cells. J Biol Chem. 1991 Feb 15;266(5):3074–3079. [PubMed] [Google Scholar]
- Nishizuka Y. Studies and perspectives of protein kinase C. Science. 1986 Jul 18;233(4761):305–312. doi: 10.1126/science.3014651. [DOI] [PubMed] [Google Scholar]
- Nishizuka Y. The role of protein kinase C in cell surface signal transduction and tumour promotion. Nature. 1984 Apr 19;308(5961):693–698. doi: 10.1038/308693a0. [DOI] [PubMed] [Google Scholar]
- Pearson R. B., Kemp B. E. Protein kinase phosphorylation site sequences and consensus specificity motifs: tabulations. Methods Enzymol. 1991;200:62–81. doi: 10.1016/0076-6879(91)00127-i. [DOI] [PubMed] [Google Scholar]
- Schnitzer J., Franke W. W., Schachner M. Immunocytochemical demonstration of vimentin in astrocytes and ependymal cells of developing and adult mouse nervous system. J Cell Biol. 1981 Aug;90(2):435–447. doi: 10.1083/jcb.90.2.435. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spruill W. A., Zysk J. R., Tres L. L., Kierszenbaum A. L. Calcium/calmodulin-dependent phosphorylation of vimentin in rat sertoli cells. Proc Natl Acad Sci U S A. 1983 Feb;80(3):760–764. doi: 10.1073/pnas.80.3.760. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spudich A., Meyer T., Stryer L. Association of the beta isoform of protein kinase C with vimentin filaments. Cell Motil Cytoskeleton. 1992;22(4):250–256. doi: 10.1002/cm.970220405. [DOI] [PubMed] [Google Scholar]
- Stasek J. E., Jr, Patterson C. E., Garcia J. G. Protein kinase C phosphorylates caldesmon77 and vimentin and enhances albumin permeability across cultured bovine pulmonary artery endothelial cell monolayers. J Cell Physiol. 1992 Oct;153(1):62–75. doi: 10.1002/jcp.1041530110. [DOI] [PubMed] [Google Scholar]
- Thorn P., Lawrie A. M., Smith P. M., Gallacher D. V., Petersen O. H. Local and global cytosolic Ca2+ oscillations in exocrine cells evoked by agonists and inositol trisphosphate. Cell. 1993 Aug 27;74(4):661–668. doi: 10.1016/0092-8674(93)90513-p. [DOI] [PubMed] [Google Scholar]
- Tokui T., Yamauchi T., Yano T., Nishi Y., Kusagawa M., Yatani R., Inagaki M. Ca2(+)-calmodulin-dependent protein kinase II phosphorylates various types of non-epithelial intermediate filament proteins. Biochem Biophys Res Commun. 1990 Jun 29;169(3):896–904. doi: 10.1016/0006-291x(90)91977-z. [DOI] [PubMed] [Google Scholar]
- Tokumitsu H., Chijiwa T., Hagiwara M., Mizutani A., Terasawa M., Hidaka H. KN-62, 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazi ne, a specific inhibitor of Ca2+/calmodulin-dependent protein kinase II. J Biol Chem. 1990 Mar 15;265(8):4315–4320. [PubMed] [Google Scholar]
- Trimmer P. A., Reier P. J., Oh T. H., Eng L. F. An ultrastructural and immunocytochemical study of astrocytic differentiation in vitro: changes in the composition and distribution of the cellular cytoskeleton. J Neuroimmunol. 1982 Jun;2(3-4):235–260. doi: 10.1016/0165-5728(82)90058-3. [DOI] [PubMed] [Google Scholar]
- Tsuda T., Griendling K. K., Alexander R. W. Angiotensin II stimulates vimentin phosphorylation via a Ca2+-dependent, protein kinase C-independent mechanism in cultured vascular smooth muscle cells. J Biol Chem. 1988 Dec 25;263(36):19758–19763. [PubMed] [Google Scholar]
- Tsujimura K., Ogawara M., Takeuchi Y., Imajoh-Ohmi S., Ha M. H., Inagaki M. Visualization and function of vimentin phosphorylation by cdc2 kinase during mitosis. J Biol Chem. 1994 Dec 9;269(49):31097–31106. [PubMed] [Google Scholar]
- Williams D. S., Park S., Schlamp C. L., Newton A. C. Protein kinase C association with the retinal cytoskeleton and phosphorylation of vimentin. Exp Eye Res. 1994 Jun;58(6):747–759. doi: 10.1006/exer.1994.1072. [DOI] [PubMed] [Google Scholar]
- Yamauchi T., Fujisawa H. Purification and characterization of the brain calmodulin-dependent protein kinase (kinase II), which is involved in the activation of tryptophan 5-monooxygenase. Eur J Biochem. 1983 Apr 15;132(1):15–21. doi: 10.1111/j.1432-1033.1983.tb07319.x. [DOI] [PubMed] [Google Scholar]
- Yamauchi T., Ohsako S., Deguchi T. Expression and characterization of calmodulin-dependent protein kinase II from cloned cDNAs in Chinese hamster ovary cells. J Biol Chem. 1989 Nov 15;264(32):19108–19116. [PubMed] [Google Scholar]
- Yano S., Fukunaga K., Ushio Y., Miyamoto E. Activation of Ca2+/calmodulin-dependent protein kinase II and phosphorylation of intermediate filament proteins by stimulation of glutamate receptors in cultured rat cortical astrocytes. J Biol Chem. 1994 Feb 18;269(7):5428–5439. [PubMed] [Google Scholar]
- Yano T., Taura C., Shibata M., Hirono Y., Ando S., Kusubata M., Takahashi T., Inagaki M. A monoclonal antibody to the phosphorylated form of glial fibrillary acidic protein: application to a non-radioactive method for measuring protein kinase activities. Biochem Biophys Res Commun. 1991 Mar 29;175(3):1144–1151. doi: 10.1016/0006-291x(91)91685-6. [DOI] [PubMed] [Google Scholar]
- Yano T., Tokui T., Nishi Y., Nishizawa K., Shibata M., Kikuchi K., Tsuiki S., Yamauchi T., Inagaki M. Phosphorylation of keratin intermediate filaments by protein kinase C, by calmodulin-dependent protein kinase and by cAMP-dependent protein kinase. Eur J Biochem. 1991 Apr 23;197(2):281–290. doi: 10.1111/j.1432-1033.1991.tb15909.x. [DOI] [PubMed] [Google Scholar]
