Abstract
We characterized the role of the E-cadherin adhesion system in the formation of epithelial tight junctions using the calcium switch model. In MDCK cells cultured in low (micromolar) calcium levels, the tight junctional protein Zonula Occludens-1 (ZO-1) is distributed intracellularly in granular clusters, the larger of which codistribute with E-cadherin. Two hours after activation of E-cadherin adhesion by transfer to normal (1.8 mM) calcium levels, ZO-1 dramatically redistributed to the cell surface, where it localized in regions rich in E-cadherin. Immunoprecipitation with ZO-1 antibodies of extracts from cells kept in low calcium and 2 h after shifting to 1.8 mM Ca2+ demonstrated the association of ZO-1 with alpha-, beta-, and gamma- catenins. E-cadherin was not detected in the ZO-1 immunoprecipitates but it was found in beta-catenin immunoprecipitates that excluded ZO-1, suggesting that the binding of ZO-1 to catenins may weaken the interaction of these proteins with E-cadherin. Immunofluorescence and immunoelectron microscopy confirmed a close association of beta-catenin and ZO-1 at 0 and 2 h after Ca2+ switch. 48 h after Ca2+ switch, upon complete polarization of the epithelium, most of the ZO-1 had segregated from lateral E-cadherin and formed a distinct, separate apical ring. The ZO-1-catenin complex was not detected in fully polarized monolayers. MDCK cells permanently transformed with Moloney sarcoma virus, which expresses low levels of E-cadherin, displayed clusters of cytoplasmic ZO-1 granules and very little of this protein at the cell surface. Upon transfection with E-cadherin into Moloney sarcoma virus-MDCK cells, ZO-1 redistributed to E-cadherin-rich lateral plasma membrane but later failed to segregate into mature tight junctions. Our experiments suggest that catenins participate in the mobilization of ZO-1 from the cytosol to the cell surface early in the development of tight junctions and that neoplastic transformation may block the formation of tight junctions, either by decreasing the levels of E-cadherin or by preventing a late event: the segregation of tight junction from the zonula adherens.
Full Text
The Full Text of this article is available as a PDF (4.7 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Anderson J. M., Stevenson B. R., Jesaitis L. A., Goodenough D. A., Mooseker M. S. Characterization of ZO-1, a protein component of the tight junction from mouse liver and Madin-Darby canine kidney cells. J Cell Biol. 1988 Apr;106(4):1141–1149. doi: 10.1083/jcb.106.4.1141. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Anderson J. M., Van Itallie C. M., Peterson M. D., Stevenson B. R., Carew E. A., Mooseker M. S. ZO-1 mRNA and protein expression during tight junction assembly in Caco-2 cells. J Cell Biol. 1989 Sep;109(3):1047–1056. doi: 10.1083/jcb.109.3.1047. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Balda M. S., Gonzalez-Mariscal L., Matter K., Cereijido M., Anderson J. M. Assembly of the tight junction: the role of diacylglycerol. J Cell Biol. 1993 Oct;123(2):293–302. doi: 10.1083/jcb.123.2.293. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Balda M. S., González-Mariscal L., Contreras R. G., Macias-Silva M., Torres-Marquez M. E., García-Sáinz J. A., Cereijido M. Assembly and sealing of tight junctions: possible participation of G-proteins, phospholipase C, protein kinase C and calmodulin. J Membr Biol. 1991 Jun;122(3):193–202. doi: 10.1007/BF01871420. [DOI] [PubMed] [Google Scholar]
- Behrens J., Birchmeier W., Goodman S. L., Imhof B. A. Dissociation of Madin-Darby canine kidney epithelial cells by the monoclonal antibody anti-arc-1: mechanistic aspects and identification of the antigen as a component related to uvomorulin. J Cell Biol. 1985 Oct;101(4):1307–1315. doi: 10.1083/jcb.101.4.1307. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Behrens J., Mareel M. M., Van Roy F. M., Birchmeier W. Dissecting tumor cell invasion: epithelial cells acquire invasive properties after the loss of uvomorulin-mediated cell-cell adhesion. J Cell Biol. 1989 Jun;108(6):2435–2447. doi: 10.1083/jcb.108.6.2435. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Behrens J., Vakaet L., Friis R., Winterhager E., Van Roy F., Mareel M. M., Birchmeier W. Loss of epithelial differentiation and gain of invasiveness correlates with tyrosine phosphorylation of the E-cadherin/beta-catenin complex in cells transformed with a temperature-sensitive v-SRC gene. J Cell Biol. 1993 Feb;120(3):757–766. doi: 10.1083/jcb.120.3.757. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Birchmeier C., Birchmeier W. Molecular aspects of mesenchymal-epithelial interactions. Annu Rev Cell Biol. 1993;9:511–540. doi: 10.1146/annurev.cb.09.110193.002455. [DOI] [PubMed] [Google Scholar]
- Boller K., Vestweber D., Kemler R. Cell-adhesion molecule uvomorulin is localized in the intermediate junctions of adult intestinal epithelial cells. J Cell Biol. 1985 Jan;100(1):327–332. doi: 10.1083/jcb.100.1.327. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cereijido M., Robbins E. S., Dolan W. J., Rotunno C. A., Sabatini D. D. Polarized monolayers formed by epithelial cells on a permeable and translucent support. J Cell Biol. 1978 Jun;77(3):853–880. doi: 10.1083/jcb.77.3.853. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Citi S. Protein kinase inhibitors prevent junction dissociation induced by low extracellular calcium in MDCK epithelial cells. J Cell Biol. 1992 Apr;117(1):169–178. doi: 10.1083/jcb.117.1.169. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Citi S., Sabanay H., Jakes R., Geiger B., Kendrick-Jones J. Cingulin, a new peripheral component of tight junctions. Nature. 1988 May 19;333(6170):272–276. doi: 10.1038/333272a0. [DOI] [PubMed] [Google Scholar]
- Citi S. The molecular organization of tight junctions. J Cell Biol. 1993 May;121(3):485–489. doi: 10.1083/jcb.121.3.485. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Diamond J. M. Twenty-first Bowditch lecture. The epithelial junction: bridge, gate, and fence. Physiologist. 1977 Feb;20(1):10–18. [PubMed] [Google Scholar]
- Edelman G. M., Crossin K. L. Cell adhesion molecules: implications for a molecular histology. Annu Rev Biochem. 1991;60:155–190. doi: 10.1146/annurev.bi.60.070191.001103. [DOI] [PubMed] [Google Scholar]
- FARQUHAR M. G., PALADE G. E. Junctional complexes in various epithelia. J Cell Biol. 1963 May;17:375–412. doi: 10.1083/jcb.17.2.375. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fleming T. P., Hay M., Javed Q., Citi S. Localisation of tight junction protein cingulin is temporally and spatially regulated during early mouse development. Development. 1993 Mar;117(3):1135–1144. doi: 10.1242/dev.117.3.1135. [DOI] [PubMed] [Google Scholar]
- Furuse M., Hirase T., Itoh M., Nagafuchi A., Yonemura S., Tsukita S., Tsukita S. Occludin: a novel integral membrane protein localizing at tight junctions. J Cell Biol. 1993 Dec;123(6 Pt 2):1777–1788. doi: 10.1083/jcb.123.6.1777. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Furuse M., Itoh M., Hirase T., Nagafuchi A., Yonemura S., Tsukita S., Tsukita S. Direct association of occludin with ZO-1 and its possible involvement in the localization of occludin at tight junctions. J Cell Biol. 1994 Dec;127(6 Pt 1):1617–1626. doi: 10.1083/jcb.127.6.1617. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gonzalez-Mariscal L., Chávez de Ramírez B., Cereijido M. Tight junction formation in cultured epithelial cells (MDCK). J Membr Biol. 1985;86(2):113–125. doi: 10.1007/BF01870778. [DOI] [PubMed] [Google Scholar]
- Goodenough D. A., Revel J. P. A fine structural analysis of intercellular junctions in the mouse liver. J Cell Biol. 1970 May;45(2):272–290. doi: 10.1083/jcb.45.2.272. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Graham F. L., van der Eb A. J. A new technique for the assay of infectivity of human adenovirus 5 DNA. Virology. 1973 Apr;52(2):456–467. doi: 10.1016/0042-6822(73)90341-3. [DOI] [PubMed] [Google Scholar]
- Gumbiner B. M., McCrea P. D. Catenins as mediators of the cytoplasmic functions of cadherins. J Cell Sci Suppl. 1993;17:155–158. doi: 10.1242/jcs.1993.supplement_17.22. [DOI] [PubMed] [Google Scholar]
- Gumbiner B., Lowenkopf T., Apatira D. Identification of a 160-kDa polypeptide that binds to the tight junction protein ZO-1. Proc Natl Acad Sci U S A. 1991 Apr 15;88(8):3460–3464. doi: 10.1073/pnas.88.8.3460. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gumbiner B., Simons K. A functional assay for proteins involved in establishing an epithelial occluding barrier: identification of a uvomorulin-like polypeptide. J Cell Biol. 1986 Feb;102(2):457–468. doi: 10.1083/jcb.102.2.457. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gumbiner B., Stevenson B., Grimaldi A. The role of the cell adhesion molecule uvomorulin in the formation and maintenance of the epithelial junctional complex. J Cell Biol. 1988 Oct;107(4):1575–1587. doi: 10.1083/jcb.107.4.1575. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gumbiner B. Structure, biochemistry, and assembly of epithelial tight junctions. Am J Physiol. 1987 Dec;253(6 Pt 1):C749–C758. doi: 10.1152/ajpcell.1987.253.6.C749. [DOI] [PubMed] [Google Scholar]
- Hamaguchi M., Matsuyoshi N., Ohnishi Y., Gotoh B., Takeichi M., Nagai Y. p60v-src causes tyrosine phosphorylation and inactivation of the N-cadherin-catenin cell adhesion system. EMBO J. 1993 Jan;12(1):307–314. doi: 10.1002/j.1460-2075.1993.tb05658.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hoschuetzky H., Aberle H., Kemler R. Beta-catenin mediates the interaction of the cadherin-catenin complex with epidermal growth factor receptor. J Cell Biol. 1994 Dec;127(5):1375–1380. doi: 10.1083/jcb.127.5.1375. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Howarth A. G., Hughes M. R., Stevenson B. R. Detection of the tight junction-associated protein ZO-1 in astrocytes and other nonepithelial cell types. Am J Physiol. 1992 Feb;262(2 Pt 1):C461–C469. doi: 10.1152/ajpcell.1992.262.2.C461. [DOI] [PubMed] [Google Scholar]
- Howarth A. G., Singer K. L., Stevenson B. R. Analysis of the distribution and phosphorylation state of ZO-1 in MDCK and nonepithelial cells. J Membr Biol. 1994 Feb;137(3):261–270. doi: 10.1007/BF00232594. [DOI] [PubMed] [Google Scholar]
- Itoh M., Nagafuchi A., Yonemura S., Kitani-Yasuda T., Tsukita S., Tsukita S. The 220-kD protein colocalizing with cadherins in non-epithelial cells is identical to ZO-1, a tight junction-associated protein in epithelial cells: cDNA cloning and immunoelectron microscopy. J Cell Biol. 1993 May;121(3):491–502. doi: 10.1083/jcb.121.3.491. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Itoh M., Yonemura S., Nagafuchi A., Tsukita S., Tsukita S. A 220-kD undercoat-constitutive protein: its specific localization at cadherin-based cell-cell adhesion sites. J Cell Biol. 1991 Dec;115(5):1449–1462. doi: 10.1083/jcb.115.5.1449. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jesaitis L. A., Goodenough D. A. Molecular characterization and tissue distribution of ZO-2, a tight junction protein homologous to ZO-1 and the Drosophila discs-large tumor suppressor protein. J Cell Biol. 1994 Mar;124(6):949–961. doi: 10.1083/jcb.124.6.949. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kemler R. From cadherins to catenins: cytoplasmic protein interactions and regulation of cell adhesion. Trends Genet. 1993 Sep;9(9):317–321. doi: 10.1016/0168-9525(93)90250-l. [DOI] [PubMed] [Google Scholar]
- Kurihara H., Anderson J. M., Farquhar M. G. Increased Tyr phosphorylation of ZO-1 during modification of tight junctions between glomerular foot processes. Am J Physiol. 1995 Mar;268(3 Pt 2):F514–F524. doi: 10.1152/ajprenal.1995.268.3.F514. [DOI] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Madara J. L. Intestinal absorptive cell tight junctions are linked to cytoskeleton. Am J Physiol. 1987 Jul;253(1 Pt 1):C171–C175. doi: 10.1152/ajpcell.1987.253.1.C171. [DOI] [PubMed] [Google Scholar]
- Marrs J. A., Andersson-Fisone C., Jeong M. C., Cohen-Gould L., Zurzolo C., Nabi I. R., Rodriguez-Boulan E., Nelson W. J. Plasticity in epithelial cell phenotype: modulation by expression of different cadherin cell adhesion molecules. J Cell Biol. 1995 Apr;129(2):507–519. doi: 10.1083/jcb.129.2.507. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McNeill H., Ozawa M., Kemler R., Nelson W. J. Novel function of the cell adhesion molecule uvomorulin as an inducer of cell surface polarity. Cell. 1990 Jul 27;62(2):309–316. doi: 10.1016/0092-8674(90)90368-o. [DOI] [PubMed] [Google Scholar]
- Meza I., Ibarra G., Sabanero M., Martínez-Palomo A., Cereijido M. Occluding junctions and cytoskeletal components in a cultured transporting epithelium. J Cell Biol. 1980 Dec;87(3 Pt 1):746–754. doi: 10.1083/jcb.87.3.746. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Navarro P., Gómez M., Pizarro A., Gamallo C., Quintanilla M., Cano A. A role for the E-cadherin cell-cell adhesion molecule during tumor progression of mouse epidermal carcinogenesis. J Cell Biol. 1991 Oct;115(2):517–533. doi: 10.1083/jcb.115.2.517. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nigam S. K., Denisenko N., Rodriguez-Boulan E., Citi S. The role of phosphorylation in development of tight junctions in cultured renal epithelial (MDCK) cells. Biochem Biophys Res Commun. 1991 Dec 16;181(2):548–553. doi: 10.1016/0006-291x(91)91224-z. [DOI] [PubMed] [Google Scholar]
- Overly C. C., Fritz L. C., Lieberburg I., McConlogue L. The beta-amyloid precursor protein is not processed by the regulated secretory pathway. Biochem Biophys Res Commun. 1991 Dec 16;181(2):513–519. doi: 10.1016/0006-291x(91)91218-2. [DOI] [PubMed] [Google Scholar]
- Ozawa M., Baribault H., Kemler R. The cytoplasmic domain of the cell adhesion molecule uvomorulin associates with three independent proteins structurally related in different species. EMBO J. 1989 Jun;8(6):1711–1717. doi: 10.1002/j.1460-2075.1989.tb03563.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peifer M. Cell adhesion and signal transduction: the Armadillo connection. Trends Cell Biol. 1995 Jun;5(6):224–229. doi: 10.1016/s0962-8924(00)89015-7. [DOI] [PubMed] [Google Scholar]
- Rajasekaran A. K., Humphrey J. S., Wagner M., Miesenböck G., Le Bivic A., Bonifacino J. S., Rodriguez-Boulan E. TGN38 recycles basolaterally in polarized Madin-Darby canine kidney cells. Mol Biol Cell. 1994 Oct;5(10):1093–1103. doi: 10.1091/mbc.5.10.1093. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rajasekaran A. K., Langhans-Rajasekaran S. A., Gould R. M., Rodriguez-Boulan E., Morimoto T. A simple biochemical approach to quantitate rough endoplasmic reticulum. Am J Physiol. 1995 Feb;268(2 Pt 1):C308–C316. doi: 10.1152/ajpcell.1995.268.2.C308. [DOI] [PubMed] [Google Scholar]
- Rodriguez-Boulan E., Nelson W. J. Morphogenesis of the polarized epithelial cell phenotype. Science. 1989 Aug 18;245(4919):718–725. doi: 10.1126/science.2672330. [DOI] [PubMed] [Google Scholar]
- Rubinfeld B., Souza B., Albert I., Müller O., Chamberlain S. H., Masiarz F. R., Munemitsu S., Polakis P. Association of the APC gene product with beta-catenin. Science. 1993 Dec 10;262(5140):1731–1734. doi: 10.1126/science.8259518. [DOI] [PubMed] [Google Scholar]
- SEDAR A. W., FORTE J. G. EFFECTS OF CALCIUM DEPLETION ON THE JUNCTIONAL COMPLEX BETWEEN OXYNTIC CELLS OF GASTRIC GLANDS. J Cell Biol. 1964 Jul;22:173–188. doi: 10.1083/jcb.22.1.173. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schneeberger E. E., Lynch R. D. Structure, function, and regulation of cellular tight junctions. Am J Physiol. 1992 Jun;262(6 Pt 1):L647–L661. doi: 10.1152/ajplung.1992.262.6.L647. [DOI] [PubMed] [Google Scholar]
- Siliciano J. D., Goodenough D. A. Localization of the tight junction protein, ZO-1, is modulated by extracellular calcium and cell-cell contact in Madin-Darby canine kidney epithelial cells. J Cell Biol. 1988 Dec;107(6 Pt 1):2389–2399. doi: 10.1083/jcb.107.6.2389. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Simons K., Fuller S. D. Cell surface polarity in epithelia. Annu Rev Cell Biol. 1985;1:243–288. doi: 10.1146/annurev.cb.01.110185.001331. [DOI] [PubMed] [Google Scholar]
- Singer K. L., Stevenson B. R., Woo P. L., Firestone G. L. Relationship of serine/threonine phosphorylation/dephosphorylation signaling to glucocorticoid regulation of tight junction permeability and ZO-1 distribution in nontransformed mammary epithelial cells. J Biol Chem. 1994 Jun 10;269(23):16108–16115. [PubMed] [Google Scholar]
- Stetler-Stevenson W. G., Aznavoorian S., Liotta L. A. Tumor cell interactions with the extracellular matrix during invasion and metastasis. Annu Rev Cell Biol. 1993;9:541–573. doi: 10.1146/annurev.cb.09.110193.002545. [DOI] [PubMed] [Google Scholar]
- Stevenson B. R., Heintzelman M. B., Anderson J. M., Citi S., Mooseker M. S. ZO-1 and cingulin: tight junction proteins with distinct identities and localizations. Am J Physiol. 1989 Oct;257(4 Pt 1):C621–C628. doi: 10.1152/ajpcell.1989.257.4.C621. [DOI] [PubMed] [Google Scholar]
- Stevenson B. R., Siliciano J. D., Mooseker M. S., Goodenough D. A. Identification of ZO-1: a high molecular weight polypeptide associated with the tight junction (zonula occludens) in a variety of epithelia. J Cell Biol. 1986 Sep;103(3):755–766. doi: 10.1083/jcb.103.3.755. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stuart R. O., Nigam S. K. Regulated assembly of tight junctions by protein kinase C. Proc Natl Acad Sci U S A. 1995 Jun 20;92(13):6072–6076. doi: 10.1073/pnas.92.13.6072. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Su L. K., Vogelstein B., Kinzler K. W. Association of the APC tumor suppressor protein with catenins. Science. 1993 Dec 10;262(5140):1734–1737. doi: 10.1126/science.8259519. [DOI] [PubMed] [Google Scholar]
- Takeichi M. Cadherin cell adhesion receptors as a morphogenetic regulator. Science. 1991 Mar 22;251(5000):1451–1455. doi: 10.1126/science.2006419. [DOI] [PubMed] [Google Scholar]
- Takeichi M. Cadherins: a molecular family important in selective cell-cell adhesion. Annu Rev Biochem. 1990;59:237–252. doi: 10.1146/annurev.bi.59.070190.001321. [DOI] [PubMed] [Google Scholar]
- Tsukita S., Itoh M., Nagafuchi A., Yonemura S., Tsukita S. Submembranous junctional plaque proteins include potential tumor suppressor molecules. J Cell Biol. 1993 Dec;123(5):1049–1053. doi: 10.1083/jcb.123.5.1049. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vega-Salas D. E., Salas P. J., Rodriguez-Boulan E. Exocytosis of vacuolar apical compartment (VAC): a cell-cell contact controlled mechanism for the establishment of the apical plasma membrane domain in epithelial cells. J Cell Biol. 1988 Nov;107(5):1717–1728. doi: 10.1083/jcb.107.5.1717. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vestweber D., Kemler R. Identification of a putative cell adhesion domain of uvomorulin. EMBO J. 1985 Dec 16;4(13A):3393–3398. doi: 10.1002/j.1460-2075.1985.tb04095.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vestweber D., Kemler R. Rabbit antiserum against a purified surface glycoprotein decompacts mouse preimplantation embryos and reacts with specific adult tissues. Exp Cell Res. 1984 May;152(1):169–178. doi: 10.1016/0014-4827(84)90241-6. [DOI] [PubMed] [Google Scholar]
- Watabe M., Nagafuchi A., Tsukita S., Takeichi M. Induction of polarized cell-cell association and retardation of growth by activation of the E-cadherin-catenin adhesion system in a dispersed carcinoma line. J Cell Biol. 1994 Oct;127(1):247–256. doi: 10.1083/jcb.127.1.247. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Willott E., Balda M. S., Fanning A. S., Jameson B., Van Itallie C., Anderson J. M. The tight junction protein ZO-1 is homologous to the Drosophila discs-large tumor suppressor protein of septate junctions. Proc Natl Acad Sci U S A. 1993 Aug 15;90(16):7834–7838. doi: 10.1073/pnas.90.16.7834. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Woods D. F., Bryant P. J. ZO-1, DlgA and PSD-95/SAP90: homologous proteins in tight, septate and synaptic cell junctions. Mech Dev. 1993 Dec;44(2-3):85–89. doi: 10.1016/0925-4773(93)90059-7. [DOI] [PubMed] [Google Scholar]
- Zahraoui A., Joberty G., Arpin M., Fontaine J. J., Hellio R., Tavitian A., Louvard D. A small rab GTPase is distributed in cytoplasmic vesicles in non polarized cells but colocalizes with the tight junction marker ZO-1 in polarized epithelial cells. J Cell Biol. 1994 Jan;124(1-2):101–115. doi: 10.1083/jcb.124.1.101. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhong Y., Saitoh T., Minase T., Sawada N., Enomoto K., Mori M. Monoclonal antibody 7H6 reacts with a novel tight junction-associated protein distinct from ZO-1, cingulin and ZO-2. J Cell Biol. 1993 Jan;120(2):477–483. doi: 10.1083/jcb.120.2.477. [DOI] [PMC free article] [PubMed] [Google Scholar]