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. 1993 Jul 1;122(1):123–135. doi: 10.1083/jcb.122.1.123

Dynamics of keratin assembly: exogenous type I keratin rapidly associates with type II keratin in vivo

PMCID: PMC2119605  PMID: 7686161

Abstract

Keratin intermediate filaments (IF) are obligate heteropolymers containing equal amounts of type I and type II keratin. We have previously shown that microinjected biotinylated type I keratin is rapidly incorporated into endogenous bundles of keratin IF (tonofilaments) of PtK2 cells. In this study we show that the earliest steps in the assembly of keratin subunits into tonofilaments involve the extremely rapid formation of discrete aggregates of microinjected keratin. These are seen as fluorescent spots containing both type I and type II keratins within 1 min post-injection as determined by double label immunofluorescence. These observations suggest that endogenous type II keratin subunits can be rapidly mobilized from their endogenous state to form complexes with the injected type I protein. Furthermore, confocal microscopy and immunogold electron microscopy suggest that the type I-type II keratin spots from in close association with the endogenous keratin IF network. When the biotinylated protein is injected at concentrations of 0.3-0.5 mg/ml, the organization of the endogenous network of tonofilaments remains undisturbed during incorporation into tonofilaments. However, microinjection of 1.5-2.0 mg/ml of biotinylated type I results in significant alterations in the organization and assembly state of the endogenous keratin IF network soon after microinjection. The results of this study are consistent with the existence of a state of equilibrium between keratin subunits and polymerized keratin IF in epithelial cells, and provide further proof that IF are dynamic elements of the cytoskeleton of mammalian cells.

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Selected References

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  1. Albers K., Fuchs E. Expression of mutant keratin cDNAs in epithelial cells reveals possible mechanisms for initiation and assembly of intermediate filaments. J Cell Biol. 1989 Apr;108(4):1477–1493. doi: 10.1083/jcb.108.4.1477. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Albers K., Fuchs E. The expression of mutant epidermal keratin cDNAs transfected in simple epithelial and squamous cell carcinoma lines. J Cell Biol. 1987 Aug;105(2):791–806. doi: 10.1083/jcb.105.2.791. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Angelides K. J., Smith K. E., Takeda M. Assembly and exchange of intermediate filament proteins of neurons: neurofilaments are dynamic structures. J Cell Biol. 1989 Apr;108(4):1495–1506. doi: 10.1083/jcb.108.4.1495. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Bader B. L., Magin T. M., Freudenmann M., Stumpp S., Franke W. W. Intermediate filaments formed de novo from tail-less cytokeratins in the cytoplasm and in the nucleus. J Cell Biol. 1991 Dec;115(5):1293–1307. doi: 10.1083/jcb.115.5.1293. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Black M. M., Keyser P., Sobel E. Interval between the synthesis and assembly of cytoskeletal proteins in cultured neurons. J Neurosci. 1986 Apr;6(4):1004–1012. doi: 10.1523/JNEUROSCI.06-04-01004.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Blikstad I., Lazarides E. Vimentin filaments are assembled from a soluble precursor in avian erythroid cells. J Cell Biol. 1983 Jun;96(6):1803–1808. doi: 10.1083/jcb.96.6.1803. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Bonifas J. M., Rothman A. L., Epstein E. H., Jr Epidermolysis bullosa simplex: evidence in two families for keratin gene abnormalities. Science. 1991 Nov 22;254(5035):1202–1205. doi: 10.1126/science.1720261. [DOI] [PubMed] [Google Scholar]
  8. 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]
  9. Cheng J., Syder A. J., Yu Q. C., Letai A., Paller A. S., Fuchs E. The genetic basis of epidermolytic hyperkeratosis: a disorder of differentiation-specific epidermal keratin genes. Cell. 1992 Sep 4;70(5):811–819. doi: 10.1016/0092-8674(92)90314-3. [DOI] [PubMed] [Google Scholar]
  10. Chipev C. C., Korge B. P., Markova N., Bale S. J., DiGiovanna J. J., Compton J. G., Steinert P. M. A leucine----proline mutation in the H1 subdomain of keratin 1 causes epidermolytic hyperkeratosis. Cell. 1992 Sep 4;70(5):821–828. doi: 10.1016/0092-8674(92)90315-4. [DOI] [PubMed] [Google Scholar]
  11. Chou C. F., Smith A. J., Omary M. B. Characterization and dynamics of O-linked glycosylation of human cytokeratin 8 and 18. J Biol Chem. 1992 Feb 25;267(6):3901–3906. [PubMed] [Google Scholar]
  12. 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]
  13. 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]
  14. Compton J. G., DiGiovanna J. J., Santucci S. K., Kearns K. S., Amos C. I., Abangan D. L., Korge B. P., McBride O. W., Steinert P. M., Bale S. J. Linkage of epidermolytic hyperkeratosis to the type II keratin gene cluster on chromosome 12q. Nat Genet. 1992 Jul;1(4):301–305. doi: 10.1038/ng0792-301. [DOI] [PubMed] [Google Scholar]
  15. Coulombe P. A., Chan Y. M., Albers K., Fuchs E. Deletions in epidermal keratins leading to alterations in filament organization in vivo and in intermediate filament assembly in vitro. J Cell Biol. 1990 Dec;111(6 Pt 2):3049–3064. doi: 10.1083/jcb.111.6.3049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Coulombe P. A., Fuchs E. Elucidating the early stages of keratin filament assembly. J Cell Biol. 1990 Jul;111(1):153–169. doi: 10.1083/jcb.111.1.153. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Coulombe P. A., Hutton M. E., Letai A., Hebert A., Paller A. S., Fuchs E. Point mutations in human keratin 14 genes of epidermolysis bullosa simplex patients: genetic and functional analyses. Cell. 1991 Sep 20;66(6):1301–1311. doi: 10.1016/0092-8674(91)90051-y. [DOI] [PubMed] [Google Scholar]
  18. Coulombe P. A., Hutton M. E., Vassar R., Fuchs E. A function for keratins and a common thread among different types of epidermolysis bullosa simplex diseases. J Cell Biol. 1991 Dec;115(6):1661–1674. doi: 10.1083/jcb.115.6.1661. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Denk H., Lackinger E., Zatloukal K., Franke W. W. Turnover of cytokeratin polypeptides in mouse hepatocytes. Exp Cell Res. 1987 Nov;173(1):137–143. doi: 10.1016/0014-4827(87)90339-9. [DOI] [PubMed] [Google Scholar]
  20. Dessev G., Iovcheva-Dessev C., Bischoff J. R., Beach D., Goldman R. A complex containing p34cdc2 and cyclin B phosphorylates the nuclear lamin and disassembles nuclei of clam oocytes in vitro. J Cell Biol. 1991 Feb;112(4):523–533. doi: 10.1083/jcb.112.4.523. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Domenjoud L., Jorcano J. L., Breuer B., Alonso A. Synthesis and fate of keratins 8 and 18 in nonepithelial cells transfected with cDNA. Exp Cell Res. 1988 Dec;179(2):352–361. doi: 10.1016/0014-4827(88)90274-1. [DOI] [PubMed] [Google Scholar]
  22. Eichner R., Bonitz P., Sun T. T. Classification of epidermal keratins according to their immunoreactivity, isoelectric point, and mode of expression. J Cell Biol. 1984 Apr;98(4):1388–1396. doi: 10.1083/jcb.98.4.1388. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Eichner R., Sun T. T., Aebi U. The role of keratin subfamilies and keratin pairs in the formation of human epidermal intermediate filaments. J Cell Biol. 1986 May;102(5):1767–1777. doi: 10.1083/jcb.102.5.1767. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Epstein E. H., Jr Molecular genetics of epidermolysis bullosa. Science. 1992 May 8;256(5058):799–804. doi: 10.1126/science.1375393. [DOI] [PubMed] [Google Scholar]
  25. 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]
  26. Eriksson J. E., Opal P., Goldman R. D. Intermediate filament dynamics. Curr Opin Cell Biol. 1992 Feb;4(1):99–104. doi: 10.1016/0955-0674(92)90065-k. [DOI] [PubMed] [Google Scholar]
  27. 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]
  28. Franke W. W., Schmid E., Mittnacht S., Grund C., Jorcano J. L. Integration of different keratins into the same filament system after microinjection of mRNA for epidermal keratins into kidney epithelial cells. Cell. 1984 Apr;36(4):813–825. doi: 10.1016/0092-8674(84)90031-x. [DOI] [PubMed] [Google Scholar]
  29. Franke W. W., Schmid E., Osborn M., Weber K. The intermediate-sized filaments in rat kangaroo PtK2 cells. II. Structure and composition of isolated filaments. Cytobiologie. 1978 Aug;17(2):392–411. [PubMed] [Google Scholar]
  30. Fuchs E., Esteves R. A., Coulombe P. A. Transgenic mice expressing a mutant keratin 10 gene reveal the likely genetic basis for epidermolytic hyperkeratosis. Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):6906–6910. doi: 10.1073/pnas.89.15.6906. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Fulton A. B., Wan K. M. Many cytoskeletal proteins associate with the hela cytoskeleton during translation in vitro. Cell. 1983 Feb;32(2):619–625. doi: 10.1016/0092-8674(83)90481-6. [DOI] [PubMed] [Google Scholar]
  32. Goldman A. E., Moir R. D., Montag-Lowy M., Stewart M., Goldman R. D. Pathway of incorporation of microinjected lamin A into the nuclear envelope. J Cell Biol. 1992 Nov;119(4):725–735. doi: 10.1083/jcb.119.4.725. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Goldman R. D., Chou Y. H., Dessev C., Dessev G., Eriksson J., Goldman A., Khuon S., Kohnken R., Lowy M., Miller R. Dynamic aspects of cytoskeletal and karyoskeletal intermediate filament systems during the cell cycle. Cold Spring Harb Symp Quant Biol. 1991;56:629–642. doi: 10.1101/sqb.1991.056.01.072. [DOI] [PubMed] [Google Scholar]
  34. Green K. J., Talian J. C., Goldman R. D. Relationship between intermediate filaments and microfilaments in cultured fibroblasts: evidence for common foci during cell spreading. Cell Motil Cytoskeleton. 1986;6(4):406–418. doi: 10.1002/cm.970060406. [DOI] [PubMed] [Google Scholar]
  35. Hatzfeld M., Franke W. W. Pair formation and promiscuity of cytokeratins: formation in vitro of heterotypic complexes and intermediate-sized filaments by homologous and heterologous recombinations of purified polypeptides. J Cell Biol. 1985 Nov;101(5 Pt 1):1826–1841. doi: 10.1083/jcb.101.5.1826. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Hatzfeld M., Weber K. Modulation of keratin intermediate filament assembly by single amino acid exchanges in the consensus sequence at the C-terminal end of the rod domain. J Cell Sci. 1991 Jun;99(Pt 2):351–362. doi: 10.1242/jcs.99.2.351. [DOI] [PubMed] [Google Scholar]
  37. Hatzfeld M., Weber K. Tailless keratins assemble into regular intermediate filaments in vitro. J Cell Sci. 1990 Oct;97(Pt 2):317–324. doi: 10.1242/jcs.97.2.317. [DOI] [PubMed] [Google Scholar]
  38. Hatzfeld M., Weber K. The coiled coil of in vitro assembled keratin filaments is a heterodimer of type I and II keratins: use of site-specific mutagenesis and recombinant protein expression. J Cell Biol. 1990 Apr;110(4):1199–1210. doi: 10.1083/jcb.110.4.1199. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. 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]
  40. Isaacs W. B., Cook R. K., Van Atta J. C., Redmond C. M., Fulton A. B. Assembly of vimentin in cultured cells varies with cell type. J Biol Chem. 1989 Oct 25;264(30):17953–17960. [PubMed] [Google Scholar]
  41. Ishida-Yamamoto A., McGrath J. A., Chapman S. J., Leigh I. M., Lane E. B., Eady R. A. Epidermolysis bullosa simplex (Dowling-Meara type) is a genetic disease characterized by an abnormal keratin-filament network involving keratins K5 and K14. J Invest Dermatol. 1991 Dec;97(6):959–968. doi: 10.1111/1523-1747.ep12491885. [DOI] [PubMed] [Google Scholar]
  42. Ishida-Yamamoto A., McGrath J. A., Judge M. R., Leigh I. M., Lane E. B., Eady R. A. Selective involvement of keratins K1 and K10 in the cytoskeletal abnormality of epidermolytic hyperkeratosis (bullous congenital ichthyosiform erythroderma). J Invest Dermatol. 1992 Jul;99(1):19–26. doi: 10.1111/1523-1747.ep12611391. [DOI] [PubMed] [Google Scholar]
  43. Jones J. C., Goldman A. E., Yang H. Y., Goldman R. D. The organizational fate of intermediate filament networks in two epithelial cell types during mitosis. J Cell Biol. 1985 Jan;100(1):93–102. doi: 10.1083/jcb.100.1.93. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Jones J. C., Green K. J. Intermediate filament-plasma membrane interactions. Curr Opin Cell Biol. 1991 Feb;3(1):127–132. doi: 10.1016/0955-0674(91)90175-x. [DOI] [PubMed] [Google Scholar]
  45. Jones S. M., Jones J. C., Goldman R. D. Fractionation of desmosomes and comparison of the polypeptide composition of desmosomes prepared from two bovine epithelial tissues. J Cell Biochem. 1988 Mar;36(3):223–236. doi: 10.1002/jcb.240360304. [DOI] [PubMed] [Google Scholar]
  46. 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]
  47. Klymkowsky M. W., Shook D. R., Maynell L. A. Evidence that the deep keratin filament systems of the Xenopus embryo act to ensure normal gastrulation. Proc Natl Acad Sci U S A. 1992 Sep 15;89(18):8736–8740. doi: 10.1073/pnas.89.18.8736. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Kulesh D. A., Ceceña G., Darmon Y. M., Vasseur M., Oshima R. G. Posttranslational regulation of keratins: degradation of mouse and human keratins 18 and 8. Mol Cell Biol. 1989 Apr;9(4):1553–1565. doi: 10.1128/mcb.9.4.1553. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Kulesh D. A., Oshima R. G. Cloning of the human keratin 18 gene and its expression in nonepithelial mouse cells. Mol Cell Biol. 1988 Apr;8(4):1540–1550. doi: 10.1128/mcb.8.4.1540. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Lane E. B., Goodman S. L., Trejdosiewicz L. K. Disruption of the keratin filament network during epithelial cell division. EMBO J. 1982;1(11):1365–1372. doi: 10.1002/j.1460-2075.1982.tb01324.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Lane E. B., Rugg E. L., Navsaria H., Leigh I. M., Heagerty A. H., Ishida-Yamamoto A., Eady R. A. A mutation in the conserved helix termination peptide of keratin 5 in hereditary skin blistering. Nature. 1992 Mar 19;356(6366):244–246. doi: 10.1038/356244a0. [DOI] [PubMed] [Google Scholar]
  52. Lersch R., Stellmach V., Stocks C., Giudice G., Fuchs E. Isolation, sequence, and expression of a human keratin K5 gene: transcriptional regulation of keratins and insights into pairwise control. Mol Cell Biol. 1989 Sep;9(9):3685–3697. doi: 10.1128/mcb.9.9.3685. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Letai A., Coulombe P. A., Fuchs E. Do the ends justify the mean? Proline mutations at the ends of the keratin coiled-coil rod segment are more disruptive than internal mutations. J Cell Biol. 1992 Mar;116(5):1181–1195. doi: 10.1083/jcb.116.5.1181. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Lu X., Lane E. B. Retrovirus-mediated transgenic keratin expression in cultured fibroblasts: specific domain functions in keratin stabilization and filament formation. Cell. 1990 Aug 24;62(4):681–696. doi: 10.1016/0092-8674(90)90114-t. [DOI] [PubMed] [Google Scholar]
  55. Ludueña R. F., Banerjee A., Khan I. A. Tubulin structure and biochemistry. Curr Opin Cell Biol. 1992 Feb;4(1):53–57. doi: 10.1016/0955-0674(92)90058-k. [DOI] [PubMed] [Google Scholar]
  56. McTavish C. F., Nelson W. J., Traub P. The turnover of vimentin in Ehrlich ascites tumour cells. FEBS Lett. 1983 Apr 18;154(2):251–256. doi: 10.1016/0014-5793(83)80159-8. [DOI] [PubMed] [Google Scholar]
  57. Miller R. K., Vikstrom K., Goldman R. D. Keratin incorporation into intermediate filament networks is a rapid process. J Cell Biol. 1991 May;113(4):843–855. doi: 10.1083/jcb.113.4.843. [DOI] [PMC free article] [PubMed] [Google Scholar]
  58. Mittal B., Sanger J. M., Sanger J. W. Visualization of intermediate filaments in living cells using fluorescently labeled desmin. Cell Motil Cytoskeleton. 1989;12(3):127–138. doi: 10.1002/cm.970120302. [DOI] [PubMed] [Google Scholar]
  59. 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]
  60. Nakamura Y., Takeda M., Angelides K. J., Tada K., Hariguchi S., Nishimura T. Assembly, disassembly, and exchange of glial fibrillary acidic protein. Glia. 1991;4(1):101–110. doi: 10.1002/glia.440040112. [DOI] [PubMed] [Google Scholar]
  61. Ngai J., Coleman T. R., Lazarides E. Localization of newly synthesized vimentin subunits reveals a novel mechanism of intermediate filament assembly. Cell. 1990 Feb 9;60(3):415–427. doi: 10.1016/0092-8674(90)90593-4. [DOI] [PubMed] [Google Scholar]
  62. Omary M. B., Baxter G. T., Chou C. F., Riopel C. L., Lin W. Y., Strulovici B. PKC epsilon-related kinase associates with and phosphorylates cytokeratin 8 and 18. J Cell Biol. 1992 May;117(3):583–593. doi: 10.1083/jcb.117.3.583. [DOI] [PMC free article] [PubMed] [Google Scholar]
  63. Parry D. A., Steven A. C., Steinert P. M. The coiled-coil molecules of intermediate filaments consist of two parallel chains in exact axial register. Biochem Biophys Res Commun. 1985 Mar 29;127(3):1012–1018. doi: 10.1016/s0006-291x(85)80045-0. [DOI] [PubMed] [Google Scholar]
  64. Peter M., Nakagawa J., Dorée M., Labbé J. C., Nigg E. A. In vitro disassembly of the nuclear lamina and M phase-specific phosphorylation of lamins by cdc2 kinase. Cell. 1990 May 18;61(4):591–602. doi: 10.1016/0092-8674(90)90471-p. [DOI] [PubMed] [Google Scholar]
  65. Raats J. M., Pieper F. R., Vree Egberts W. T., Verrijp K. N., Ramaekers F. C., Bloemendal H. Assembly of amino-terminally deleted desmin in vimentin-free cells. J Cell Biol. 1990 Nov;111(5 Pt 1):1971–1985. doi: 10.1083/jcb.111.5.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  66. Rosevear E. R., McReynolds M., Goldman R. D. Dynamic properties of intermediate filaments: disassembly and reassembly during mitosis in baby hamster kidney cells. Cell Motil Cytoskeleton. 1990;17(3):150–166. doi: 10.1002/cm.970170303. [DOI] [PubMed] [Google Scholar]
  67. Rothnagel J. A., Dominey A. M., Dempsey L. D., Longley M. A., Greenhalgh D. A., Gagne T. A., Huber M., Frenk E., Hohl D., Roop D. R. Mutations in the rod domains of keratins 1 and 10 in epidermolytic hyperkeratosis. Science. 1992 Aug 21;257(5073):1128–1130. doi: 10.1126/science.257.5073.1128. [DOI] [PubMed] [Google Scholar]
  68. Rueger D. C., Huston J. S., Dahl D., Bignami A. Formation of 100 A filaments from purified glial fibrillary acidic protein in vitro. J Mol Biol. 1979 Nov 25;135(1):53–68. doi: 10.1016/0022-2836(79)90340-1. [DOI] [PubMed] [Google Scholar]
  69. Skalli O., Chou Y. H., Goldman R. D. Intermediate filaments: not so tough after all. Trends Cell Biol. 1992 Oct;2(10):308–312. doi: 10.1016/0962-8924(92)90121-3. [DOI] [PubMed] [Google Scholar]
  70. Skalli O., Goldman R. D. Recent insights into the assembly, dynamics, and function of intermediate filament networks. Cell Motil Cytoskeleton. 1991;19(2):67–79. doi: 10.1002/cm.970190202. [DOI] [PubMed] [Google Scholar]
  71. Soellner P., Quinlan R. A., Franke W. W. Identification of a distinct soluble subunit of an intermediate filament protein: tetrameric vimentin from living cells. Proc Natl Acad Sci U S A. 1985 Dec;82(23):7929–7933. doi: 10.1073/pnas.82.23.7929. [DOI] [PMC free article] [PubMed] [Google Scholar]
  72. 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]
  73. Steinert P. M. Analysis of the mechanism of assembly of mouse keratin 1/keratin 10 intermediate filaments in vitro suggests that intermediate filaments are built from multiple oligomeric units rather than a unique tetrameric building block. J Struct Biol. 1991 Oct;107(2):175–188. doi: 10.1016/1047-8477(91)90020-w. [DOI] [PubMed] [Google Scholar]
  74. Steinert P. M., Idler W. W. Postsynthetic modifications of mammalian epidermal alpha-keratin. Biochemistry. 1979 Dec 11;18(25):5664–5669. doi: 10.1021/bi00592a022. [DOI] [PubMed] [Google Scholar]
  75. Steinert P. M., Liem R. K. Intermediate filament dynamics. Cell. 1990 Feb 23;60(4):521–523. doi: 10.1016/0092-8674(90)90651-t. [DOI] [PubMed] [Google Scholar]
  76. Steinert P. M., Rice R. H., Roop D. R., Trus B. L., Steven A. C. Complete amino acid sequence of a mouse epidermal keratin subunit and implications for the structure of intermediate filaments. Nature. 1983 Apr 28;302(5911):794–800. doi: 10.1038/302794a0. [DOI] [PubMed] [Google Scholar]
  77. Steinert P. M. The dynamic phosphorylation of the human intermediate filament keratin 1 chain. J Biol Chem. 1988 Sep 15;263(26):13333–13339. [PubMed] [Google Scholar]
  78. Steinert P. M. The two-chain coiled-coil molecule of native epidermal keratin intermediate filaments is a type I-type II heterodimer. J Biol Chem. 1990 May 25;265(15):8766–8774. [PubMed] [Google Scholar]
  79. Stoler A., Kopan R., Duvic M., Fuchs E. Use of monospecific antisera and cRNA probes to localize the major changes in keratin expression during normal and abnormal epidermal differentiation. J Cell Biol. 1988 Aug;107(2):427–446. doi: 10.1083/jcb.107.2.427. [DOI] [PMC free article] [PubMed] [Google Scholar]
  80. Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
  81. Trevor K. T. Disruption of keratin filaments in embryonic epithelial cell types. New Biol. 1990 Nov;2(11):1004–1014. [PubMed] [Google Scholar]
  82. Vassar R., Coulombe P. A., Degenstein L., Albers K., Fuchs E. Mutant keratin expression in transgenic mice causes marked abnormalities resembling a human genetic skin disease. Cell. 1991 Jan 25;64(2):365–380. doi: 10.1016/0092-8674(91)90645-f. [DOI] [PubMed] [Google Scholar]
  83. Vikstrom K. L., Borisy G. G., Goldman R. D. Dynamic aspects of intermediate filament networks in BHK-21 cells. Proc Natl Acad Sci U S A. 1989 Jan;86(2):549–553. doi: 10.1073/pnas.86.2.549. [DOI] [PMC free article] [PubMed] [Google Scholar]
  84. Vikstrom K. L., Lim S. S., Goldman R. D., Borisy G. G. Steady state dynamics of intermediate filament networks. J Cell Biol. 1992 Jul;118(1):121–129. doi: 10.1083/jcb.118.1.121. [DOI] [PMC free article] [PubMed] [Google Scholar]
  85. Vikstrom K. L., Miller R. K., Goldman R. D. Analyzing dynamic properties of intermediate filaments. Methods Enzymol. 1991;196:506–525. doi: 10.1016/0076-6879(91)96044-r. [DOI] [PubMed] [Google Scholar]
  86. Ward G. E., Kirschner M. W. Identification of cell cycle-regulated phosphorylation sites on nuclear lamin C. Cell. 1990 May 18;61(4):561–577. doi: 10.1016/0092-8674(90)90469-u. [DOI] [PubMed] [Google Scholar]
  87. Wiegers W., Höner B., Traub P. Microinjection of intermediate filament proteins into living cells with and without preexisting intermediate filament network. Cell Biol Int Rep. 1991 Apr;15(4):287–296. doi: 10.1016/0309-1651(91)90167-h. [DOI] [PubMed] [Google Scholar]
  88. Woodcock-Mitchell J., Eichner R., Nelson W. G., Sun T. T. Immunolocalization of keratin polypeptides in human epidermis using monoclonal antibodies. J Cell Biol. 1982 Nov;95(2 Pt 1):580–588. doi: 10.1083/jcb.95.2.580. [DOI] [PMC free article] [PubMed] [Google Scholar]
  89. Yang H. Y., Lieska N., Goldman A. E., Goldman R. D. A 300,000-mol-wt intermediate filament-associated protein in baby hamster kidney (BHK-21) cells. J Cell Biol. 1985 Feb;100(2):620–631. doi: 10.1083/jcb.100.2.620. [DOI] [PMC free article] [PubMed] [Google Scholar]

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