Abstract
The expression of keratin 18 (K18) is restricted in humans primarily to a variety of single layered or simple epithelia. However, direct introduction of a cloned K18 gene into cultured, somatic cells by DNA transfection has been shown to result in the promiscuous expression of K18 even while the endogenous mouse form of K18 (Endo B) remains silent. To determine if the cloned K18 genomic DNA fragment contains sufficient information to be regulated appropriately when subjected to a normal developmental environment, and to determine if the cloned gene is expressed in diverse epithelia, the K18 gene, including 2.5 kb of 5' flanking sequence and 3.5 kb of 3' flanking sequence, has been introduced into the germ line of mice. Mice from all three resulting K18 transgenic lines express the gene in an appropriate tissue-specific pattern that includes hepatocytes, simple epithelia of the intestinal tract, ductal cells of several glands and epithelial cells of the thymus. No expression of K18 was found in muscle, heart, or in most of the brain even in mice carrying 18 copies of the K18 gene. In most tissues, the level of K18 RNA was directly proportional to copy number and was as efficiently expressed as the endogenous Endo B gene. The K18 protein was identified by both protein blotting methods and indirect immunofluorescence staining. No pathological consequences of overexpression of the K18 gene were observed. The cloned K18 gene appears to contain all cis-acting DNA sequences necessary for appropriate expression. In addition, diverse epithelial cell types are able to express this single human gene.
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- Blumenberg M. Concerted gene duplications in the two keratin gene families. J Mol Evol. 1988;27(3):203–211. doi: 10.1007/BF02100075. [DOI] [PubMed] [Google Scholar]
- Bode J., Maass K. Chromatin domain surrounding the human interferon-beta gene as defined by scaffold-attached regions. Biochemistry. 1988 Jun 28;27(13):4706–4711. doi: 10.1021/bi00413a019. [DOI] [PubMed] [Google Scholar]
- Bosch F. X., Leube R. E., Achtstätter T., Moll R., Franke W. W. Expression of simple epithelial type cytokeratins in stratified epithelia as detected by immunolocalization and hybridization in situ. J Cell Biol. 1988 May;106(5):1635–1648. doi: 10.1083/jcb.106.5.1635. [DOI] [PMC free article] [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]
- Brûlet P., Babinet C., Kemler R., Jacob F. Monoclonal antibodies against trophectoderm-specific markers during mouse blastocyst formation. Proc Natl Acad Sci U S A. 1980 Jul;77(7):4113–4117. doi: 10.1073/pnas.77.7.4113. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chirgwin J. M., Przybyla A. E., MacDonald R. J., Rutter W. J. Isolation of biologically active ribonucleic acid from sources enriched in ribonuclease. Biochemistry. 1979 Nov 27;18(24):5294–5299. doi: 10.1021/bi00591a005. [DOI] [PubMed] [Google Scholar]
- Chisholm J. C., Houliston E. Cytokeratin filament assembly in the preimplantation mouse embryo. Development. 1987 Nov;101(3):565–582. doi: 10.1242/dev.101.3.565. [DOI] [PubMed] [Google Scholar]
- Cooper D., Schermer A., Sun T. T. Classification of human epithelia and their neoplasms using monoclonal antibodies to keratins: strategies, applications, and limitations. Lab Invest. 1985 Mar;52(3):243–256. [PubMed] [Google Scholar]
- Dente L., Rüther U., Tripodi M., Wagner E. F., Cortese R. Expression of human alpha 1-acid glycoprotein genes in cultured cells and in transgenic mice. Genes Dev. 1988 Feb;2(2):259–266. doi: 10.1101/gad.2.2.259. [DOI] [PubMed] [Google Scholar]
- 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]
- Duprey P., Morello D., Vasseur M., Babinet C., Condamine H., Brûlet P., Jacob F. Expression of the cytokeratin endo A gene during early mouse embryogenesis. Proc Natl Acad Sci U S A. 1985 Dec;82(24):8535–8539. doi: 10.1073/pnas.82.24.8535. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Emerson J. A. Disruption of the cytokeratin filament network in the preimplantation mouse embryo. Development. 1988 Oct;104(2):219–234. doi: 10.1242/dev.104.2.219. [DOI] [PubMed] [Google Scholar]
- Feinberg A. P., Vogelstein B. A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity. Anal Biochem. 1983 Jul 1;132(1):6–13. doi: 10.1016/0003-2697(83)90418-9. [DOI] [PubMed] [Google Scholar]
- Fox N., Crooke R., Hwang L. H., Schibler U., Knowles B. B., Solter D. Metastatic hibernomas in transgenic mice expressing an alpha-amylase-SV40 T antigen hybrid gene. Science. 1989 Apr 28;244(4903):460–463. doi: 10.1126/science.2785714. [DOI] [PubMed] [Google Scholar]
- Franko M. C., Gibbs C. J., Jr, Rhoades D. A., Gajdusek D. C. Monoclonal antibody analysis of keratin expression in the central nervous system. Proc Natl Acad Sci U S A. 1987 May;84(10):3482–3485. doi: 10.1073/pnas.84.10.3482. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Geisler N., Weber K. Amino acid sequence data on glial fibrillary acidic protein (GFA); implications for the subdivision of intermediate filaments into epithelial and non-epithelial members. EMBO J. 1983;2(11):2059–2063. doi: 10.1002/j.1460-2075.1983.tb01700.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Heid H. W., Moll I., Franke W. W. Patterns of expression of trichocytic and epithelial cytokeratins in mammalian tissues. I. Human and bovine hair follicles. Differentiation. 1988;37(2):137–157. doi: 10.1111/j.1432-0436.1988.tb00805.x. [DOI] [PubMed] [Google Scholar]
- Ichinose Y., Morita T., Zhang F. Y., Srimahasongcram S., Tondella M. L., Matsumoto M., Nozaki M., Matsushiro A. Nucleotide sequence and structure of the mouse cytokeratin endoB gene. Gene. 1988 Oct 15;70(1):85–95. doi: 10.1016/0378-1119(88)90107-2. [DOI] [PubMed] [Google Scholar]
- Jackson B. W., Grund C., Schmid E., Bürki K., Franke W. W., Illmensee K. Formation of cytoskeletal elements during mouse embryogenesis. Intermediate filaments of the cytokeratin type and desmosomes in preimplantation embryos. Differentiation. 1980;17(3):161–179. doi: 10.1111/j.1432-0436.1980.tb01093.x. [DOI] [PubMed] [Google Scholar]
- Julien J. P., Grosveld F., Yazdanbaksh K., Flavell D., Meijer D., Mushynski W. The structure of a human neurofilament gene (NF-L): a unique exon-intron organization in the intermediate filament gene family. Biochim Biophys Acta. 1987 Jun 6;909(1):10–20. doi: 10.1016/0167-4781(87)90041-8. [DOI] [PubMed] [Google Scholar]
- Julien J. P., Tretjakoff I., Beaudet L., Peterson A. Expression and assembly of a human neurofilament protein in transgenic mice provide a novel neuronal marking system. Genes Dev. 1987 Dec;1(10):1085–1095. doi: 10.1101/gad.1.10.1085. [DOI] [PubMed] [Google Scholar]
- Knapp A. C., Franke W. W. Spontaneous losses of control of cytokeratin gene expression in transformed, non-epithelial human cells occurring at different levels of regulation. Cell. 1989 Oct 6;59(1):67–79. doi: 10.1016/0092-8674(89)90870-2. [DOI] [PubMed] [Google Scholar]
- 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]
- 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]
- Kulesh D. A., Oshima R. G. Complete structure of the gene for human keratin 18. Genomics. 1989 Apr;4(3):339–347. doi: 10.1016/0888-7543(89)90340-6. [DOI] [PubMed] [Google Scholar]
- Kuruc N., Franke W. W. Transient coexpression of desmin and cytokeratins 8 and 18 in developing myocardial cells of some vertebrate species. Differentiation. 1988 Sep;38(3):177–193. doi: 10.1111/j.1432-0436.1988.tb00212.x. [DOI] [PubMed] [Google Scholar]
- Labarca C., Paigen K. A simple, rapid, and sensitive DNA assay procedure. Anal Biochem. 1980 Mar 1;102(2):344–352. doi: 10.1016/0003-2697(80)90165-7. [DOI] [PubMed] [Google Scholar]
- Meinkoth J., Wahl G. Hybridization of nucleic acids immobilized on solid supports. Anal Biochem. 1984 May 1;138(2):267–284. doi: 10.1016/0003-2697(84)90808-x. [DOI] [PubMed] [Google Scholar]
- Moll R., Franke W. W., Schiller D. L., Geiger B., Krepler R. The catalog of human cytokeratins: patterns of expression in normal epithelia, tumors and cultured cells. Cell. 1982 Nov;31(1):11–24. doi: 10.1016/0092-8674(82)90400-7. [DOI] [PubMed] [Google Scholar]
- Moll R., Levy R., Czernobilsky B., Hohlweg-Majert P., Dallenbach-Hellweg G., Franke W. W. Cytokeratins of normal epithelia and some neoplasms of the female genital tract. Lab Invest. 1983 Nov;49(5):599–610. [PubMed] [Google Scholar]
- Monteiro M. J., Cleveland D. W. Expression of NF-L and NF-M in fibroblasts reveals coassembly of neurofilament and vimentin subunits. J Cell Biol. 1989 Feb;108(2):579–593. doi: 10.1083/jcb.108.2.579. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Oshima R. G., Abrams L., Kulesh D. Activation of an intron enhancer within the keratin 18 gene by expression of c-fos and c-jun in undifferentiated F9 embryonal carcinoma cells. Genes Dev. 1990 May;4(5):835–848. doi: 10.1101/gad.4.5.835. [DOI] [PubMed] [Google Scholar]
- Oshima R. G., Howe W. E., Klier F. G., Adamson E. D., Shevinsky L. H. Intermediate filament protein synthesis in preimplantation murine embryos. Dev Biol. 1983 Oct;99(2):447–455. doi: 10.1016/0012-1606(83)90294-4. [DOI] [PubMed] [Google Scholar]
- Oshima R. G. Identification and immunoprecipitation of cytoskeletal proteins from murine extra-embryonic endodermal cells. J Biol Chem. 1981 Aug 10;256(15):8124–8133. [PubMed] [Google Scholar]
- Oshima R. G., Millán J. L., Ceceña G. Comparison of mouse and human keratin 18: a component of intermediate filaments expressed prior to implantation. Differentiation. 1986;33(1):61–68. doi: 10.1111/j.1432-0436.1986.tb00411.x. [DOI] [PubMed] [Google Scholar]
- Oshima R. G., Trevor K., Shevinsky L. H., Ryder O. A., Ceceña G. Identification of the gene coding for the Endo B murine cytokeratin and its methylated, stable inactive state in mouse nonepithelial cells. Genes Dev. 1988 May;2(5):505–516. doi: 10.1101/gad.2.5.505. [DOI] [PubMed] [Google Scholar]
- Otsuka A. S., Price P. A. Removal of proteases from DNase I by chromatography over agarose with covalently attached lima bean protease inhibitor. Anal Biochem. 1974 Nov;62(1):180–187. doi: 10.1016/0003-2697(74)90379-0. [DOI] [PubMed] [Google Scholar]
- Pieper F. R., Schaart G., Krimpenfort P. J., Henderik J. B., Moshage H. J., van de Kemp A., Ramaekers F. C., Berns A., Bloemendal H. Transgenic expression of the muscle-specific intermediate filament protein desmin in nonmuscle cells. J Cell Biol. 1989 Mar;108(3):1009–1024. doi: 10.1083/jcb.108.3.1009. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Quax W., van den Broek L., Egberts W. V., Ramaekers F., Bloemendal H. Characterization of the hamster desmin gene: expression and formation of desmin filaments in nonmuscle cells after gene transfer. Cell. 1985 Nov;43(1):327–338. doi: 10.1016/0092-8674(85)90038-8. [DOI] [PubMed] [Google Scholar]
- Quinlan R. A., Cohlberg J. A., Schiller D. L., Hatzfeld M., Franke W. W. Heterotypic tetramer (A2D2) complexes of non-epidermal keratins isolated from cytoskeletons of rat hepatocytes and hepatoma cells. J Mol Biol. 1984 Sep 15;178(2):365–388. doi: 10.1016/0022-2836(84)90149-9. [DOI] [PubMed] [Google Scholar]
- Ramaekers F. C., Moesker O., Huysmans A., Schaart G., Westerhof G., Wagenaar S. S., Herman C. J., Vooijs G. P. Intermediate filament proteins in the study of tumor heterogeneity: an in-depth study of tumors of the urinary and respiratory tracts. Ann N Y Acad Sci. 1985;455:614–634. doi: 10.1111/j.1749-6632.1985.tb50440.x. [DOI] [PubMed] [Google Scholar]
- Singer P. A., Trevor K., Oshima R. G. Molecular cloning and characterization of the Endo B cytokeratin expressed in preimplantation mouse embryos. J Biol Chem. 1986 Jan 15;261(2):538–547. [PubMed] [Google Scholar]
- Steinert P. M., Roop D. R. Molecular and cellular biology of intermediate filaments. Annu Rev Biochem. 1988;57:593–625. doi: 10.1146/annurev.bi.57.070188.003113. [DOI] [PubMed] [Google Scholar]
- Stief A., Winter D. M., Strätling W. H., Sippel A. E. A nuclear DNA attachment element mediates elevated and position-independent gene activity. Nature. 1989 Sep 28;341(6240):343–345. doi: 10.1038/341343a0. [DOI] [PubMed] [Google Scholar]
- 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]
- Trevor K., Oshima R. G. Preimplantation mouse embryos and liver express the same type I keratin gene product. J Biol Chem. 1985 Dec 15;260(29):15885–15891. [PubMed] [Google Scholar]
- Tölle H. G., Weber K., Osborn M. Microinjection of monoclonal antibodies specific for one intermediate filament protein in cells containing multiple keratins allow insight into the composition of particular 10 nm filaments. Eur J Cell Biol. 1985 Sep;38(2):234–244. [PubMed] [Google Scholar]
- Vassar R., Rosenberg M., Ross S., Tyner A., Fuchs E. Tissue-specific and differentiation-specific expression of a human K14 keratin gene in transgenic mice. Proc Natl Acad Sci U S A. 1989 Mar;86(5):1563–1567. doi: 10.1073/pnas.86.5.1563. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Virtanen I., Miettinen M., Lehto V. P., Kariniemi A. L., Paasivuo R. Diagnostic application of monoclonal antibodies to intermediate filaments. Ann N Y Acad Sci. 1985;455:635–648. doi: 10.1111/j.1749-6632.1985.tb50441.x. [DOI] [PubMed] [Google Scholar]
- Wu Y. J., Parker L. M., Binder N. E., Beckett M. A., Sinard J. H., Griffiths C. T., Rheinwald J. G. The mesothelial keratins: a new family of cytoskeletal proteins identified in cultured mesothelial cells and nonkeratinizing epithelia. Cell. 1982 Dec;31(3 Pt 2):693–703. doi: 10.1016/0092-8674(82)90324-5. [DOI] [PubMed] [Google Scholar]
- Zimmerman K., Legouy E., Stewart V., Depinho R., Alt F. W. Differential regulation of the N-myc gene in transfected cells and transgenic mice. Mol Cell Biol. 1990 May;10(5):2096–2103. doi: 10.1128/mcb.10.5.2096. [DOI] [PMC free article] [PubMed] [Google Scholar]
