51
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Hirt RP, Poulain-Godefroy O, Billotte J, Kraehenbuhl JP, Fasel N. Highly inducible synthesis of heterologous proteins in epithelial cells carrying a glucocorticoid-responsive vector. Gene 1992; 111:199-206. [PMID: 1347276 DOI: 10.1016/0378-1119(92)90687-k] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A glucocorticoid-responsive vector is described which allows for the highly inducible expression of complementary DNAs (cDNAs) in stably transfected mammalian cell lines. This vector, pLK-neo, composed of a variant mouse mammary tumor virus long terminal repeat promoter, containing a hormone regulatory element, a Geneticin resistance-encoding gene in a simian virus 40 transcription unit, and a polylinker insertion site for heterologous cDNAs, was used to express the polymeric immunoglobulin (poly-Ig) receptor and the thymocyte marker, Thy-1, in Madin-Darby canine kidney (MDCK) cells and in murine fibroblast L cells. A high level of poly-Ig receptor or Thy-1 mRNA accumulation was observed in MDCK cells in response to dexamethasone with a parallel ten- to 200-fold increase in protein synthesis depending on the recombinant protein and the transfected cell clone.
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Affiliation(s)
- R P Hirt
- Institute of Biochemistry, University of Lausanne, Epalinges, Switzerland
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52
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Saucan L, Palade GE. Differential colchicine effects on the transport of membrane and secretory proteins in rat hepatocytes in vivo: bipolar secretion of albumin. Hepatology 1992; 15:714-21. [PMID: 1551647 DOI: 10.1002/hep.1840150427] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We carried out a comparative investigation on the effects of colchicine (25 mumoles/100 gm body wt) on the intracellular transport, processing and discharge by secretion or proteolytic processing of a membrane protein (i.e., the polymeric IgA receptor) and a secretory protein (i.e., albumin) in rat hepatocytes. The results obtained indicated the following: (a) the transport and processing of polymeric IgA receptor is strongly inhibited and delayed, but the appearance of secretory component in the bile is not arrested; (b) polymeric IgA receptor reaches the sinusoidal plasmalemma in colchicine-treated specimens, as it does in controls; (c) albumin discharge into the plasma is strongly inhibited and markedly delayed in colchicine-treated as compared with control animals; (d) the reverse applies for albumin secretion in the bile, which is increased by a large factor; (e) newly synthesized albumin secreted directly from hepatocytes in control and in colchicine-treated animals is the major source of bile albumin; and (f) colchicine affects in different ways the polymeric IgA receptor and albumin arrival at the sinusoidal front and especially at the biliary front of the hepatocyte.
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Affiliation(s)
- L Saucan
- Division of Cellular and Molecular Medicine, University of California, San Diego, La Jolla 92093
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53
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Davidson HW, McGowan CH, Balch WE. Evidence for the regulation of exocytic transport by protein phosphorylation. J Cell Biol 1992; 116:1343-55. [PMID: 1311711 PMCID: PMC2289369 DOI: 10.1083/jcb.116.6.1343] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We investigated the effects of the protein phosphatase inhibitors okadaic acid and microcystin-LR upon transport of newly synthesized proteins through the exocytic pathway. Treatment of CHO cells with 1 microM okadaic acid rapidly inhibited movement of a marker protein (vesicular stomatitis virus G protein) from the endoplasmic reticulum to the Golgi compartment. Both okadaic acid and microcystin-LR also inhibited transport in an in vitro assay reconstituting movement to the Golgi compartment, at concentrations equivalent to those required to inhibit phosphorylase phosphatase activity. Inhibition both in vivo and in vitro could be antagonized by protein kinase inhibitors, suggesting that protein phosphorylation was directly responsible for this effect. An early stage in the transport reaction associated with vesicle formation or targeting was inhibited by protein phosphorylation, which could be reversed by fractions enriched in protein phosphatase 2A. Protein kinase antagonists did not inhibit transport between sequential compartments of the exocytic pathway in vitro, suggesting that protein phosphorylation is not itself required for vesicular transport. During mitosis, vesicular transport is inhibited simultaneous to the activation of maturation-promoting factor. It is proposed that the inhibition caused by okadaic acid and microcystin-LR involves a similar mechanism to that responsible for the mitotic arrest of vesicular transport.
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Affiliation(s)
- H W Davidson
- Department of Cell Biology, Scripps Research Institute, La Jolla, California 92037
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54
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Eskelinen S, Huotari V, Sormunen R, Palovuori R, Kok JW, Lehto VP. Low intracellular pH induces redistribution of fodrin and instabilization of lateral walls in MDCK cells. J Cell Physiol 1992; 150:122-33. [PMID: 1309822 DOI: 10.1002/jcp.1041500117] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have studied the effect of intracellular pH on the establishment and maintenance of the cellular polarity in MDCK cells by utilizing nigericin which causes lowering of the cytoplasmic pH. At pH below 6.5, MDCK cells lost their polarized morphology and became roundish, with an increased apical area and shortened and unstable lateral walls. The lateral wall marker proteins uvomorulin and Na,K-ATPase remained segregated to the lateral walls in the acidified cells, as shown by immunofluorescence microscopy. Fodrin, on the other hand, was released from its normal basolateral residence and was found in the cytoplasm. Actin, which normally co-localizes with fodrin along the basolateral walls, showed a dotty distribution in the cytoplasm of acidified cells, while stress fibers remained intact. Microtubular network appeared flattened, but the Golgi complex retained its apical position. The pH change-induced alterations were readily reversible, as the normal basal-apical polarity (columnar shape, distinct apical and lateral domains with apposing and stiff lateral membranes) was reformed within 10 minutes after restoring the normal pH gradient across the cell membrane. This coincided with the translocation of fodrin from the cytoplasm to the lateral walls. The results show that lowering of intracellular pH leads to temporary segregation of fodrin from the other components of the membrane skeleton assembly, and that association of fodrin with the lateral walls seems to be a prerequisite for their close apposition and for the maintenance of normal basal-axial polarity.
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55
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Yamagami K, Hamazaki TS, Yasumasu S, Masuda K, Iuchi I. Molecular and cellular basis of formation, hardening, and breakdown of the egg envelope in fish. INTERNATIONAL REVIEW OF CYTOLOGY 1992; 136:51-92. [PMID: 1506146 DOI: 10.1016/s0074-7696(08)62050-1] [Citation(s) in RCA: 111] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- K Yamagami
- Life Science Institute, Sophia University, Tokyo, Japan
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56
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Nabi IR, Le Bivic A, Fambrough D, Rodriguez-Boulan E. An endogenous MDCK lysosomal membrane glycoprotein is targeted basolaterally before delivery to lysosomes. J Cell Biol 1991; 115:1573-84. [PMID: 1757463 PMCID: PMC2289220 DOI: 10.1083/jcb.115.6.1573] [Citation(s) in RCA: 96] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Using surface immunoprecipitation at 37 degrees C to "catch" the transient apical or basolateral appearance of an endogenous MDCK lysosomal membrane glycoprotein, the AC17 antigen, we demonstrate that the bulk of newly synthesized AC17 antigen is polarly targeted from the Golgi apparatus to the basolateral plasma membrane or early endosomes and is then transported to lysosomes via the endocytic pathway. The AC17 antigen exhibits very similar properties to members of the family of lysosomal-associated membrane glycoproteins (LAMPs). Parallel studies of an avian LAMP, LEP100, transfected into MDCK cells revealed colocalization of the two proteins to lysosomes, identical biosynthetic and degradation rates, and similar low levels of steady-state expression on both the apical (0.8%) and basolateral (2.1%) membranes. After treatment of the cells with chloroquine, newly synthesized AC17 antigen, while still initially targeted basolaterally, appears stably in both the apical and basolateral domains, consistent with the depletion of the AC17 antigen from lysosomes and its recycling in a nonpolar fashion to the cell surface.
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Affiliation(s)
- I R Nabi
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York 10021
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57
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Neutral endopeptidase, a major brush border protein of the kidney proximal nephron, is directly targeted to the apical domain when expressed in Madin-Darby canine kidney cells. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)55066-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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58
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Involvement of both vectorial and transcytotic pathways in the preferential apical cell surface localization of rat dipeptidyl peptidase IV in transfected LLC-PK1 cells. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)55050-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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59
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Hunziker W, Harter C, Matter K, Mellman I. Basolateral sorting in MDCK cells requires a distinct cytoplasmic domain determinant. Cell 1991; 66:907-20. [PMID: 1909606 DOI: 10.1016/0092-8674(91)90437-4] [Citation(s) in RCA: 236] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In MDCK cells, Golgi to basolateral transport of several membrane proteins has been found to involve a cytoplasmic domain determinant. In some cases (Fc receptor, lysosomal glycoprotein Igp120), the determinant appears similar to that required for endocytosis via clathrin-coated pits; for Igp120, elimination of a single cytoplasmic domain tyrosine both blocks internalization and results in apical transport. In other cases (LDL receptor), the determinant does not involve the cytoplasmic domain tyrosine required for endocytosis. Thus, contrary to current models, basolateral transport in MCDK cells occurs not by default but depends on one or more cytoplasmic domain determinants, the precise nature of which is unknown. For some proteins, it is closely related to coated pit determinants. The fact that many membrane proteins can reach the apical surface in the absence of this determinant suggests that signals for apical transport are widely distributed.
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Affiliation(s)
- W Hunziker
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510
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60
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Apical cell surface expression of rat dipeptidyl peptidase IV in transfected Madin-Darby canine kidney cells. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)98852-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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61
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Abstract
The cell surface membrane is the boundary between a cell and its environment. In case of polarized epithelial cells, the apical plasma membrane is frequently the boundary between an organism and its environment. The plasmalemma possesses the elements that endow a cell with the capacity to converse with its environment. Plasmalemmal receptor and transducer proteins allow the cell to recognize and respond to various external influences. Membrane-associated proteins anchor cells to their substrata and mediate their integration into tissues. Many properties of a given cell type may be attributed to the protein composition of its plasma membrane. Most cells go to large lengths to control the nature and distribution of polypeptides that populate their plasmalemmas. Cells regulate the expression of genes encoding plasma membrane proteins. Proteins destined for the insertion into the plasma membrane pass through a complex system of processing organelles prior to arriving at their site of ultimate functional residence. Each of these organelles makes a unique contribution to the maturation of these proteins as they transit through them. This chapter discusses the postsynthetic steps involved in the biogenesis of plasma membrane proteins. The chapter discusses some of the events common to all plasmalemmal polypeptides, with special emphasis on those that contribute directly to the character of the cell surface. The chapter then discusses the specializations, associated with cell types, possessing differentiated cell surface sub-domains. The chapter highlights some of the important and fascinating questions confronting investigators interested in the cell biology of the plasma membrane.
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62
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Affiliation(s)
- R W Compans
- Department of Microbiology, University of Alabama, Birmingham 35294
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63
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Wessels HP, Hansen GH, Fuhrer C, Look AT, Sjöström H, Norén O, Spiess M. Aminopeptidase N is directly sorted to the apical domain in MDCK cells. J Cell Biol 1990; 111:2923-30. [PMID: 1980123 PMCID: PMC2116386 DOI: 10.1083/jcb.111.6.2923] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In different epithelial cell types, integral membrane proteins appear to follow different sorting pathways to the apical surface. In hepatocytes, several apical proteins were shown to be transported there indirectly via the basolateral membrane, whereas in MDCK cells a direct sorting pathway from the trans-Golgi-network to the apical membrane has been demonstrated. However, different proteins had been studied in these cells. To compare the sorting of a single protein in both systems, we have expressed aminopeptidase N, which already had been shown to be sorted indirectly in hepatocytes, in transfected MDCK cells. As expected, it was predominantly localized to the apical domain of the plasma membrane. By monitoring the appearance of newly synthesized aminopeptidase N at the apical and basolateral surface, it was found to be directly sorted to the apical domain in MDCK cells, indicating that the sorting pathways are indeed cell type-specific.
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Affiliation(s)
- H P Wessels
- Department of Biochemistry, University of Basel, Switzerland
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64
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Abstract
Given the role of microtubules in directing the transport of many intracellular organelles, we investigated whether intact microtubules were also required for transcytosis across epithelia. Using polarized MDCK cells expressing receptors for the Fc domain of IgG (FcRII-B2) or polymeric immunoglobulin (pIg-R), we examined the involvement of microtubules in apical to basolateral and basolateral to apical transcytosis, respectively. While depolymerization of microtubules with nocodozole had no effect on apical to basolateral transcytosis via FcR, basolateral to apical transcytosis of dimeric IgA via pIg-R was almost completely blocked. Inhibition due to nocodozole was selective for basolateral to apical transcytosis, since neither endocytosis nor receptor recycling was significantly affected at either plasma membrane domain. As shown by confocal microscopy, the block in transcytosis was due to the inability of MDCK cells to translocate IgA-containing vesicles from the basolateral to the apical cytoplasm in the absence of an intact microtubule network. The nocodazole sensitive step could be partially by-passed, however, by allowing cells to internalize IgA at 17 degrees C prior to nocodazole treatment. Although incubation at 17 degrees C blocked release of IgA into the apical medium, it did not prevent translocation of IgA-containing vesicles to the apical cytoplasm. Thus, receptor-mediated transcytosis in opposite directions exhibits distinct requirements for microtubules, a feature which reflects the spatial organization of MDCK cells.
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Affiliation(s)
- W Hunziker
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510
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65
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van Zeijl MJ, Matlin KS. Microtubule perturbation inhibits intracellular transport of an apical membrane glycoprotein in a substrate-dependent manner in polarized Madin-Darby canine kidney epithelial cells. CELL REGULATION 1990; 1:921-36. [PMID: 1983109 PMCID: PMC362862 DOI: 10.1091/mbc.1.12.921] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of microtubule perturbation on the transport of two different viral glycoproteins were examined in infected Madin-Darby canine kidney (MDCK) cells grown on both permeable and solid substrata. Quantitative biochemical analysis showed that the microtubule-depolymerizing drug nocodazole inhibited arrival of influenza hemagglutinin on the apical plasma membrane in MDCK cells grown on both substrata. In contrast, the microtubule-stabilizing drug taxol inhibited apical appearance of hemagglutinin only when MDCK cells were grown on permeable substrata. On the basis of hemagglutinin mobility on sodium dodecyl sulfate gels and its sensitivity to endo H, it was evident that nocodazole and taxol arrested hemagglutinin at different intracellular sites. Neither drug caused a significant increase in the amount of hemagglutinin detected on the basolateral plasma membrane domain. In addition, neither drug had any noticeable effect on the transport of the vesicular stomatitis virus (VSV)-G protein to the basolateral surface. These results shed light on previous conflicting reports using this model system and support the hypothesis that microtubules play a role in the delivery of membrane glycoproteins to the apical, but not the basolateral, domain of epithelial cells.
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Affiliation(s)
- M J van Zeijl
- Department of Anatomy and Cellular Biology, Harvard Medical School, Boston, Massachusetts 02115
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66
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Le Bivic A, Quaroni A, Nichols B, Rodriguez-Boulan E. Biogenetic pathways of plasma membrane proteins in Caco-2, a human intestinal epithelial cell line. J Cell Biol 1990; 111:1351-61. [PMID: 1976637 PMCID: PMC2116246 DOI: 10.1083/jcb.111.4.1351] [Citation(s) in RCA: 185] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We studied the sorting and surface delivery of three apical and three basolateral proteins in the polarized epithelial cell line Caco-2, using pulse-chase radiolabeling and surface domain-selective biotinylation (Le Bivic, A., F. X. Real, and E. Rodriguez-Boulan. 1989. Proc. Natl. Acad. Sci. USA. 86:9313-9317). While the basolateral proteins (antigen 525, HLA-I, and transferrin receptor) were targeted directly and efficiently to the basolateral membrane, the apical markers (sucrase-isomaltase [SI], aminopeptidase N [APN], and alkaline phosphatase [ALP]) reached the apical membrane by different routes. The large majority (80%) of newly synthesized ALP was directly targeted to the apical surface and the missorted basolateral pool was very inefficiently transcytosed. SI was more efficiently targeted to the apical membrane (greater than 90%) but, in contrast to ALP, the missorted basolateral pool was rapidly transcytosed. Surprisingly, a distinct peak of APN was detected on the basolateral domain before its accumulation in the apical membrane; this transient basolateral pool (at least 60-70% of the enzyme reaching the apical surface, as measured by continuous basal addition of antibodies) was efficiently transcytosed. In contrast with their transient basolateral expression, apical proteins were more stably localized on the apical surface, apparently because of their low endocytic capability in this membrane. Thus, compared with two other well-characterized epithelial models, MDCK cells and the hepatocyte, Caco-2 cells have an intermediate sorting phenotype, with apical proteins using both direct and indirect pathways, and basolateral proteins using only direct pathways, during biogenesis.
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Affiliation(s)
- A Le Bivic
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York 10021
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67
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Wandinger-Ness A, Bennett MK, Antony C, Simons K. Distinct transport vesicles mediate the delivery of plasma membrane proteins to the apical and basolateral domains of MDCK cells. J Cell Biol 1990; 111:987-1000. [PMID: 2202740 PMCID: PMC2116280 DOI: 10.1083/jcb.111.3.987] [Citation(s) in RCA: 232] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Immunoisolation techniques have led to the purification of apical and basolateral transport vesicles that mediate the delivery of proteins from the trans-Golgi network to the two plasma membrane domains of MDCK cells. We showed previously that these transport vesicles can be formed and released in the presence of ATP from mechanically perforated cells (Bennett, M. K., A. Wandinger-Ness, and K. Simons, 1988. EMBO (Euro. Mol. Biol. Organ.) J. 7:4075-4085). Using virally infected cells, we have monitored the purification of the trans-Golgi derived vesicles by following influenza hemagglutinin or vesicular stomatitis virus (VSV) G protein as apical and basolateral markers, respectively. Equilibrium density gradient centrifugation revealed that hemagglutinin containing vesicles had a slightly lower density than those containing VSV-G protein, indicating that the two fractions were distinct. Antibodies directed against the cytoplasmically exposed domains of the viral spike glycoproteins permitted the resolution of apical and basolateral vesicle fractions. The immunoisolated vesicles contained a subset of the proteins present in the starting fraction. Many of the proteins were sialylated as expected for proteins existing the trans-Golgi network. The two populations of vesicles contained a number of proteins in common, as well as components which were enriched up to 38-fold in one fraction relative to the other. Among the unique components, a number of transmembrane proteins could be identified using Triton X-114 phase partitioning. This work provides evidence that two distinct classes of vesicles are responsible for apical and basolateral protein delivery. Common protein components are suggested to be involved in vesicle budding and fusion steps, while unique components may be required for specific recognition events such as those involved in protein sorting and vesicle targeting.
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Affiliation(s)
- A Wandinger-Ness
- Cell Biology Program, European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany
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68
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McNeill H, Ozawa M, Kemler R, Nelson WJ. Novel function of the cell adhesion molecule uvomorulin as an inducer of cell surface polarity. Cell 1990; 62:309-16. [PMID: 2164888 DOI: 10.1016/0092-8674(90)90368-o] [Citation(s) in RCA: 335] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Na+,K(+)-ATPase has distinctly different distributions in mesenchymal cells, where it has an unrestricted distribution over the entire cell surface, compared with polarized epithelial cells, where it is restricted to the basal-lateral membrane domain. The generation of this restricted distribution is important in mesenchyme to epithelia conversion in development and the function of transporting epithelia, but the mechanisms involved are unknown. Here we show that expression of the epithelial CAM uvomorulin in transfected fibroblasts is sufficient to induce a redistribution of Na+,K(+)-ATPase to sites of uvomorulin-mediated cell-cell contacts, similar to that in polarized epithelial cells. This restricted distribution of Na+,K(+)-ATPase occurs in the absence of tight junctions but coincides with the reorganization of the membrane cytoskeleton. The results indicate a direct role for CAMs as inducers of cell surface polarity of selective cytoplasmic and membrane proteins.
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Affiliation(s)
- H McNeill
- Institute for Cancer Research, Philadelphia, Pennsylvania 19111
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69
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Dotti CG, Simons K. Polarized sorting of viral glycoproteins to the axon and dendrites of hippocampal neurons in culture. Cell 1990; 62:63-72. [PMID: 2163770 DOI: 10.1016/0092-8674(90)90240-f] [Citation(s) in RCA: 359] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cultured hippocampal neurons were infected with a temperature-sensitive mutant of vesicular stomatitis virus (VSV) and a wild-type strain of the avian influenza fowl plague virus (FPV). The intracellular distribution of viral glycoproteins was monitored by immunofluorescence microscopy. In mature, fully polarized neurons the VSV glycoprotein (a basolateral protein in epithelial MDCK cells) moved from the Golgi complex to the dendritic domain, whereas the hemagglutinin protein of FPV (an apically sorted protein in MDCK cells) was targeted preferentially, but not exclusively, to the axon. The VSV glycoprotein appeared in clusters on the dendritic surface, while the hemagglutinin was distributed uniformly along the axonal membrane. Based on the finding that the same viral glycoproteins are sorted in a polarized fashion in both neuronal and epithelial cells, we propose that the molecular mechanisms of surface protein sorting share common features in the two cell types.
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Affiliation(s)
- C G Dotti
- Cell Biology Program, European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany
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70
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Le Bivic A, Sambuy Y, Mostov K, Rodriguez-Boulan E. Vectorial targeting of an endogenous apical membrane sialoglycoprotein and uvomorulin in MDCK cells. J Biophys Biochem Cytol 1990; 110:1533-9. [PMID: 2335561 PMCID: PMC2200188 DOI: 10.1083/jcb.110.5.1533] [Citation(s) in RCA: 132] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We studied the cell-surface delivery pathways of newly synthesized membrane glycoproteins in MDCK cells and for this purpose we characterized an endogenous apical integral membrane glycoprotein. By combining a pulse-chase protocol with domain-selective cell-surface biotinylation, immune precipitation, and streptavidin-agarose precipitation (Le Bivic et al. 1989. Proc. Natl. Acad. Sci USA. 86:9313-9317), we followed the appearance at the cell surface of a major apical sialoglycoprotein, gp114, a basolateral protein, uvomorulin, and a transcytosing protein, the polyimmunoglobulin receptor (pIg-R). We determined that both gp114 and uvomorulin appeared to be delivered directly to their respective surface, with mistargeting levels of 8 and 2%, respectively. Using the same technique, the pIg-R was first detected on the basolateral domain and then on the apical domain, to be finally released into the apical medium, as described (Mostov, K. E., and D. L. Deitcher. 1986. Cell. 46:613-621). To directly determine whether the gp114 pool present on the basolateral surface was a precursor of the apical gp114, we compared it with the equivalent pIg-R pool, by labeling with sulfo-NHS-SS-biotin, a cleavable, tight junction-impermeable probe, and by following the fraction of this probe that became resistant to basal glutathione and accessible to apical glutathione during incubation at 37 degrees C. We found that, contrary to pIg-R, basolateral gp114 was poorly endocytosed and was not transcytosed to the apical side. These results demonstrate that an endogenous apical integral membrane glycoprotein of Madin-Darby canine kidney cells is sorted intracellularly and is vectorially targeted to the apical surface.
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Affiliation(s)
- A Le Bivic
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York 10021
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71
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Schaerer E, Verrey F, Racine L, Tallichet C, Reinhardt M, Kraehenbuhl JP. Polarized transport of the polymeric immunoglobulin receptor in transfected rabbit mammary epithelial cells. J Cell Biol 1990; 110:987-98. [PMID: 1691196 PMCID: PMC2116109 DOI: 10.1083/jcb.110.4.987] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A cDNA for the rabbit low Mr polymeric immunoglobulin (poly-Ig) receptor was expressed in an immortalized rabbit mammary cell line. The intracellular routing of the receptor and its cell surface expression was analyzed in stably transfected cells grown on permeable supports. Initially the cells formed a monolayer with no transmural electrical resistance. All monolayer cells expressed the poly-Ig receptor and cytokeratin 7 filaments characteristic of luminal mammary cells but absent in myoepithelial cells. Within 7 d in culture, the cells underwent cytodifferentiation and formed a bilayer with a transepithelial electrical resistance of approximately 500 omega x cm2. Upper layer cells formed tight junctions with adjacent cells and gap junctions with basal cells. Expression of the poly-Ig receptor and cytokeratin 7 was restricted to the cells from the upper layer. The kinetics of receptor biosynthesis and processing was similar to that reported for rabbit mammary gland and rat liver. The receptor was cleaved at the apical cell surface and release of secretory component into the apical medium occurred with a half-time of approximately 2 h. Selective cell surface trypsinization combined with pulse-chase experiments served to determine at which cell surface domain newly synthesized receptor appeared first. The receptor was digested with a half-time of approximately 60 min with trypsin present in the basolateral medium and 90 min with apical trypsin. These data are consistent with selective targeting of newly synthesized receptor to the basolateral surface. The results indicate that transcytosis of the receptor from basolateral to apical membrane in the presence or the absence of its ligand requires approximately 30 min. Cleavage of the receptor by endogenous protease is not concomitant with its appearance at the apical surface, but requires additional time, thus explaining the presence of intact receptor on the apical membrane.
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Affiliation(s)
- E Schaerer
- Swiss Institute for Experimental Cancer Research, University of Lausanne
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72
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Chang A, Jamieson JD. Structural and Secretory Polarity in the Pancreatic Acinar Cell. Compr Physiol 1989. [DOI: 10.1002/cphy.cp060327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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73
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Le Bivic A, Real FX, Rodriguez-Boulan E. Vectorial targeting of apical and basolateral plasma membrane proteins in a human adenocarcinoma epithelial cell line. Proc Natl Acad Sci U S A 1989; 86:9313-7. [PMID: 2687880 PMCID: PMC298485 DOI: 10.1073/pnas.86.23.9313] [Citation(s) in RCA: 170] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
We studied the surface delivery pathways followed by newly synthesized plasma membrane proteins in intestinal cells. To this end, we developed an assay and characterized an epithelial cell line (SK-CO-15) derived from human colon adenocarcinoma. Polarized confluent monolayers (2000 omega.cm2), grown on polycarbonate filter chambers, were pulsed with radioactive methionine/cysteine and, at different times of chase, the protein fraction reaching the apical or basolateral surface was recovered by domain-selective biotinylation, immunoprecipitation, and immobilized streptavidin precipitation. Both an apical and a basolateral marker were found to be delivered vectorially to the respective surface, with a sorting efficiency of 50:1 for the basolateral marker and 14:1 for the apical marker.
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Affiliation(s)
- A Le Bivic
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York, NY 10021
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74
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Lisanti MP, Le Bivic A, Sargiacomo M, Rodriguez-Boulan E. Steady-state distribution and biogenesis of endogenous Madin-Darby canine kidney glycoproteins: evidence for intracellular sorting and polarized cell surface delivery. J Biophys Biochem Cytol 1989; 109:2117-27. [PMID: 2808522 PMCID: PMC2115858 DOI: 10.1083/jcb.109.5.2117] [Citation(s) in RCA: 141] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
We used domain-selective biotinylation/125I-streptavidin blotting (Sargiacomo, M., M. P. Lisanti, L. Graeve, A. Le Bivic, and E. Rodriguez-Boulan. 1989 J. Membr. Biol. 107:277-286), in combination with lectin precipitation, to analyze the apical and basolateral glycoprotein composition of Madin-Darby canine kidney (MDCK) cells and to explore the role of glycosylation in the targeting of membrane glycoproteins. All six lectins used recognized both apical and basolateral glycoproteins, indicating that none of the sugar moieties detected were characteristic of the particular epithelial cell surface. Pulse-chase experiments coupled with domain-selective glycoprotein recovery were designed to detect the initial appearance of newly synthesized glycoproteins at the apical or basolateral cell surface. After a short pulse with a radioactive precursor, glycoproteins reaching each surface were biotinylated, extracted, and recovered via precipitation with immobilized streptavidin. Several basolateral glycoproteins (including two sulfated proteins) and at least two apical glycoproteins (one of them the major sulfated protein of MDCK cells) appeared at the corresponding surface after 20-40 min of chase, but were not detected in the opposite surface, suggesting that they were sorted intracellularly and vectorially delivered to their target membrane. Several "peripheral" apical proteins were detected at maximal levels on the apical surface immediately after the 15-min pulse, suggesting a very fast intracellular transit. Finally, domain-selective labeling of surface carbohydrates with biotin hydrazide (after periodate oxidation) revealed strikingly different integral and peripheral glycoprotein patterns, resembling the Con A pattern, after labeling with sulfo-N-hydroxy-succinimido-biotin. The approaches described here should be useful in characterizing the steady-state distribution and biogenesis of endogenous cell surface components in a variety of epithelial cell lines.
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Affiliation(s)
- M P Lisanti
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York 10021
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75
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Abstract
Polarized epithelial cells play fundamental roles in the ontogeny and function of a variety of tissues and organs in mammals. The morphogenesis of a sheet of polarized epithelial cells (the trophectoderm) is the first overt sign of cellular differentiation in early embryonic development. In the adult, polarized epithelial cells line all body cavities and occur in tissues that carry out specialized vectorial transport functions of absorption and secretion. The generation of this phenotype is a multistage process requiring extracellular cues and the reorganization of proteins in the cytoplasm and on the plasma membrane; once established, the phenotype is maintained by the segregation and retention of specific proteins and lipids in distinct apical and basal-lateral plasma membrane domains.
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Affiliation(s)
- E Rodriguez-Boulan
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York, NY 10021
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76
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Cereijido M, Ponce A, Gonzalez-Mariscal L. Tight junctions and apical/basolateral polarity. J Membr Biol 1989. [DOI: 10.1007/bf01870987] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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77
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Lepage T, Gache C. Purification and Characterization of the Sea Urchin Embryo Hatching Enzyme. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)83659-6] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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78
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Skibbens JE, Roth MG, Matlin KS. Differential extractability of influenza virus hemagglutinin during intracellular transport in polarized epithelial cells and nonpolar fibroblasts. J Biophys Biochem Cytol 1989; 108:821-32. [PMID: 2522097 PMCID: PMC2115377 DOI: 10.1083/jcb.108.3.821] [Citation(s) in RCA: 173] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Biochemical changes in the influenza virus hemagglutinin during intracellular transport to the apical plasma membrane of epithelial cells were investigated in Madin-Darby canine kidney (MDCK) cells and in LLC-PK1 cells stably transfected with a hemagglutinin gene. After pulse-labeling a substantial fraction of hemagglutinin was observed to become insoluble in isotonic solutions of Triton X-100. Insolubility of hemagglutinin was detected late in the transport pathway after addition of complex sugars in the Golgi complex but before insertion of the protein in the plasma membrane. Insolubility was not dependent on oligosaccharide modification since deoxymannojirimycin (dMM), which inhibits mannose trimming, failed to prevent its onset. Insolubility was not due to assembly of virus particles at the plasma membrane because insoluble hemagglutinin was also observed in transfected cells. Hemagglutinin insolubility was also seen in MDCK cells cultured in suspension and in chick embryo fibroblasts, indicating that insolubility and plasma membrane polarity are not simply correlated. In addition to insolubility, an apparent transport-dependent reduction of the disulfide bond linking HA1 and HA2 in hemagglutinin was detected. Because of the timing of both insolubility and the loss of the disulfide bond, these modifications may be important in the delivery of the hemagglutinin to the cell surface.
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Affiliation(s)
- J E Skibbens
- Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, Texas 77030
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79
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Rodriguez-Boulan E, Salas PJ, Sargiacomo M, Lisanti M, Lebivic A, Sambuy Y, Vega-Salas D, Graeve L. Methods to estimate the polarized distribution of surface antigens in cultured epithelial cells. Methods Cell Biol 1989; 32:37-56. [PMID: 2691857 DOI: 10.1016/s0091-679x(08)61166-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- E Rodriguez-Boulan
- Cornell University Medical College, Department of Cell Biology and Anatomy, New York, New York 10021
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80
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Wessels HP, Geffen I, Spiess M. A hepatocyte-specific basolateral membrane protein is targeted to the same domain when expressed in Madin-Darby canine kidney cells. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(17)31217-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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81
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Bennett MK, Wandinger-Ness A, De Curtis I, Antony C, Simons K, Kartenbeck J. Perforated cells for studying intracellular membrane transport. Methods Cell Biol 1989; 31:103-26. [PMID: 2779446 DOI: 10.1016/s0091-679x(08)61604-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- M K Bennett
- European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany
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82
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Bennett MK, Wandinger-Ness A, Simons K. Release of putative exocytic transport vesicles from perforated MDCK cells. EMBO J 1988; 7:4075-85. [PMID: 3243273 PMCID: PMC455116 DOI: 10.1002/j.1460-2075.1988.tb03301.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Mechanically perforated MDCK cells were used to study membrane transport between the trans-Golgi network and the apical and basolateral plasma membrane domains in vitro. Three membrane transport markers--an apical protein (fowl plague virus haemagglutinin), a basolateral protein (vesicular stomatitis virus G protein), and a lipid marker destined for both domains (C6-NBD-sphingomyelin)--were each accumulated in the trans-Golgi by a 20 degrees C block of transport and their behaviour monitored following cell perforation and incubation at 37 degrees C. In the presence of ATP and in the absence of calcium ions a considerable fraction of the transport markers were released from the perforated cells in sealed membrane vesicles. Control experiments showed that the vesicles were not generated by non-specific vesiculation of the Golgi complex or the plasma membrane. The vesicles had well defined sedimentation properties and the orientation expected of transport vesicles derived from the trans-Golgi network.
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Affiliation(s)
- M K Bennett
- European Molecular Biology Laboratory, Heidelberg, FRG
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83
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Salas PJ, Vega-Salas DE, Hochman J, Rodriguez-Boulan E, Edidin M. Selective anchoring in the specific plasma membrane domain: a role in epithelial cell polarity. J Cell Biol 1988; 107:2363-76. [PMID: 3198691 PMCID: PMC2115698 DOI: 10.1083/jcb.107.6.2363] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
We have studied the role of restrictions to lateral mobility in the segregation of proteins to apical and basolateral domains of MDCK epithelial cells. Radioimmunoassay and semiquantitative video analysis of immunofluorescence on frozen sections showed that one apical and three basolateral glycoproteins, defined by monoclonal antibodies and binding of beta-2-microglobulin, were incompletely extracted with 0.5% Triton X-100 in a buffer that preserves the cortical cytoskeleton (Fey, E. G., K. M. Wan, and S. Penman. 1984. J. Cell Biol. 98:1973-1984; Nelson, W. T. and P. J. Veshnock. 1986. J. Cell Biol. 103:1751-1766). The marker proteins were preferentially extracted from the "incorrect" domain (i.e., the apical domain for a basolateral marker), indicating that the cytoskeletal anchoring was most effective on the "correct" domain. The two basolateral markers were unpolarized and almost completely extractable in cells prevented from establishing cell-cell contacts by incubation in low Ca++ medium, while an apical marker was only extracted from the basal surface under the same conditions. Procedures were developed to apply fluorescent probes to either the apical or the basolateral surface of live cells grown on native collagen gels. Fluorescence recovery after photobleaching of predominantly basolateral antigens showed a large percent of cells (28-52%) with no recoverable fluorescence on the basal domain but normal fluorescence recovery on the apical surface of most cells (92-100%). Diffusion coefficients in cells with normal fluorescence recovery were in the order of 1.1 x 10(-9) cm2/s in the apical domain and 0.6-0.9 x 10(-9) cm2/s in the basal surface, but the difference was not significant. The data from both techniques indicate (a) the existence of mobile and immobile protein fractions in both plasma membrane domains, and (b) that linkage to a domain specific submembrane cytoskeleton plays an important role in the maintenance of epithelial cell surface polarity.
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Affiliation(s)
- P J Salas
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York 10021
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84
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Vega-Salas DE, Salas PJ, 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; 107:1717-28. [PMID: 3053735 PMCID: PMC2115332 DOI: 10.1083/jcb.107.5.1717] [Citation(s) in RCA: 124] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The vacuolar apical compartment (VAC) is an organelle found in Madin-Darby canine kidney (MDCK) cells with incomplete intercellular contacts by incubation in 5 microM Ca++ and in cells without contacts (single cells in subconfluent culture); characteristically, it displays apical biochemical markers and microvilli and excludes basolateral markers (Vega-Salas, D. E., P. J. I. Salas, and E. Rodriguez-Boulan. 1987. J. Cell Biol. 104:1249-1259). The apical surface of cells kept under these culture conditions is immature, with reduced numbers of microvilli and decreased levels of an apical biochemical marker (184 kD), which is, however, still highly polarized (Vega-Salas, D. E., P. J. I. Salas, D. Gundersen, and E. Rodriguez-Boulan. 1987. J. Cell Biol. 104:905-916). We describe here the morphological stages of VAC exocytosis which ultimately lead to the establishment of a differentiated apical domain. Addition of 1.8 mM Ca++ to monolayers developed in 5 microM Ca++ causes the rapid (20-40 min) fusion of VACs with the plasma membrane and their accessibility to external antibodies, as demonstrated by immunofluorescence, immunoperoxidase EM, and RIA with antibodies against the 184-kD apical plasma membrane marker. Exocytosis occurs towards areas of cell-cell contact in the developing lateral surface where they form intercellular pockets; fusion images are always observed immediately adjacent to the incomplete junctional bands detected by the ZO-1 antibody (Stevenson, B. R., J. D. Siliciano, M. S. Mooseker, and D. A. Goodenough. 1986. J. Cell Biol. 103:755-766). Blocks of newly incorporated VAC microvilli and 184-kD protein progressively move from intercellular ("primitive" lateral) spaces towards the microvilli-poor free cell surface. The definitive lateral domain is sealed behind these blocks by the growing tight junctional fence. These results demonstrate a fundamental role of cell-cell contact-mediated VAC exocytosis in the establishment of epithelial surface polarity. Because isolated stages (intercellular pockets) of the stereotyped sequence of events triggered by the establishment of intercellular contacts in MDCK cells have been reported during normal differentiation of intestine epithelium (Colony, P. C., and M. R. Neutra. 1983. Dev. Biol. 97:349-363), we speculate that the mechanism we describe here plays an important role in the establishment of epithelial cell polarity in vivo.
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Affiliation(s)
- D E Vega-Salas
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York 10021
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85
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Bergmann JE, Fusco PJ. The M protein of vesicular stomatitis virus associates specifically with the basolateral membranes of polarized epithelial cells independently of the G protein. J Cell Biol 1988; 107:1707-15. [PMID: 2846585 PMCID: PMC2115312 DOI: 10.1083/jcb.107.5.1707] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Using monoclonal antibodies and indirect immunofluorescence microscopy, we investigated the distribution of the M protein in situ in vesicular stomatitis virus-(VSV) infected MDCK cells. M protein was observed free in the cytoplasm and associated with the plasma membrane. Using the ts045 mutant of VSV to uncouple the synthesis and transport of the VSV G protein we demonstrated that this distribution was not related to the presence of G protein on the cell surface. Sections of epon-embedded infected cells labeled with antibody to the M protein and processed for indirect horseradish peroxidase immunocytochemistry revealed that the M protein was associated specifically with the basolateral plasma membrane. The G and M proteins of VSV have therefore evolved features which bring them independently to the basolateral membrane of polarized epithelial cells and allow virus to bud specifically from that membrane.
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Affiliation(s)
- J E Bergmann
- Department of Anatomy and Cell Biology, Columbia University College of Physicians and Surgeons, New York 10032
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86
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Fisher JM, Sossin W, Newcomb R, Scheller RH. Multiple neuropeptides derived from a common precursor are differentially packaged and transported. Cell 1988; 54:813-22. [PMID: 3409320 DOI: 10.1016/s0092-8674(88)91131-2] [Citation(s) in RCA: 165] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The ELH prohormone is proteolytically processed into at least nine peptides which govern egg-laying behavior in Aplysia. Quantitative immunocytochemistry demonstrates that peptides derived from the prohormone are packaged into distinct vesicle classes. Further experiments suggest the segregation occurs via a rapid initial proteolytic cleavage of the prohormone followed by sorting at the trans Golgi. Egg-laying hormone (ELH) immunoreactivity is localized to the cell body and processes, while bag cell peptide (BCP) immunoreactivity is greater in the cell body. Steady state levels of the amino-terminal set of peptides including the BCPs are 3- to 8-fold lower than the carboxy-terminal cleavage products, such as ELH. Thus, intracellular packaging and routing of the peptides cleaved from a single prohormone regulate their localization and levels in these neurons.
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Affiliation(s)
- J M Fisher
- Department of Biological Sciences, Stanford University, California 94305
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87
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Affiliation(s)
- K Simons
- European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany
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88
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Rindler MJ, Traber MG. A specific sorting signal is not required for the polarized secretion of newly synthesized proteins from cultured intestinal epithelial cells. J Cell Biol 1988; 107:471-9. [PMID: 2458357 PMCID: PMC2115219 DOI: 10.1083/jcb.107.2.471] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Caco-2 cells, derived from human colon, have the morphological, functional, and biochemical properties of small intestinal epithelial cells. After infection with enveloped viruses, influenza virions assembled at the apical plasma membrane while vesicular stomatitis virus (VSV) particles appeared exclusively at the basolateral membrane, similar to the pattern observed in virus-infected Madin-Darby canine kidney (MDCK). When grown in Millicell filter chamber devices and labeled with [35S]methionine, Caco-2 monolayers released all of their radiolabeled secretory products preferentially into the basal chamber. Among the proteins identified were apolipoproteins AI and E, transferrin, and alpha-fetoprotein. No proteins were observed to be secreted preferentially from the apical cell surface. The lysosomal enzyme beta-hexosaminidase was also secreted primarily from the basolateral surface of the cells in the presence or absence of lysosomotropic drugs or tunicamycin, which inhibit the targetting of lysosomal enzymes to lysosomes. Neither of these drug treatments significantly affected the polarized secretion of other nonlysosomal proteins. In addition, growth hormone (GH), which is released in a nonpolar fashion from MDCK cells, was secreted exclusively from the basolateral membrane after transfection of Caco-2 cells with GH cDNA in a pSV2-based expression vector. Similar results were obtained in transient expression experiments and after selection of permanently transformed Caco-2 cells expressing GH. Since both beta-hexosaminidase and GH would be expected to lack sorting signals for polarized exocytosis in epithelial cells, these results indicate that in intestinal cells, proteins transported via the basolateral secretory pathway need not have specific sorting signals.
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Affiliation(s)
- M J Rindler
- Department of Cell Biology, New York University Medical Center, New York 10016
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89
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Haffar OK, Aponte GW, Bravo DA, John NJ, Hess RT, Firestone GL. Glucocorticoid-regulated localization of cell surface glycoproteins in rat hepatoma cells is mediated within the Golgi complex. J Biophys Biochem Cytol 1988; 106:1463-74. [PMID: 2836430 PMCID: PMC2115045 DOI: 10.1083/jcb.106.5.1463] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Glucocorticoid hormones regulate the post-translational maturation and sorting of cell surface and extracellular mouse mammary tumor virus (MMTV) glycoproteins in M1.54 cells, a stably infected rat hepatoma cell line. Exposure to monensin significantly reduced the proteolytic maturation and externalization of viral glycoproteins resulting in a stable cellular accumulation of a single 70,000-Mr glycosylated polyprotein (designated gp70). Cell surface- and intracellular-specific immunoprecipitations of monensin-treated cells revealed that gp70 can be localized to the cell surface only in the presence of 1 microM dexamethasone, while in uninduced cells gp70 is irreversibly sequestered in an intracellular compartment. Analysis of oligosaccharide processing kinetics demonstrated that gp70 acquired resistance to endoglycosidase H with a half-time of 65 min in the presence or absence of hormone. In contrast, gp70 was inefficiently galactosylated after a 60-min lag in uninduced cells while rapidly acquiring this carbohydrate modification in the presence of dexamethasone. Furthermore, in the absence or presence of monensin, MMTV glycoproteins failed to be galactosylated in hormone-induced CR4 cells, a complement-selected sorting variant defective in the glucocorticoid-regulated compartmentalization of viral glycoproteins to the cell surface. Since dexamethasone had no apparent global effects on organelle morphology or production of total cell surface-galactosylated species, we conclude that glucocorticoids induce the localization of cell surface MMTV glycoproteins by regulating a highly selective step within the Golgi apparatus after the acquisition of endoglycosidase H-resistant oligosaccharide side chains but before or at the site of galactose attachment.
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Affiliation(s)
- O K Haffar
- Department of Physiology-Anatomy, University of California, Berkeley 94720
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90
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Spiegel S, Matyas GR, Cheng L, Sacktor B. Asymmetric distribution of gangliosides in rat renal brush-border and basolateral membranes. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 938:270-8. [PMID: 3342237 DOI: 10.1016/0005-2736(88)90165-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Highly enriched brush-border and basolateral membranes isolated from rat renal cortex were used to study the distribution of endogenous gangliosides in the two distinct plasma membrane domains of epithelial cells. These two membrane domains differed in their glycolipid composition. The basolateral membranes contained more of both neutral and acidic glycolipids, expressed on a protein basis. In both membranes, the neutral glycolipids corresponding to mono-, di-, tri- and tetraglycosylceramides were present. The basolateral membranes contained more diglycosylceramide than the brush-border membranes. The major gangliosides found were GM4, GM3, and GD3 with minor amounts of GM1 and GD1a. The latter were identified and quantified by sensitive iodinated cholera toxin binding assays. When the distribution of individual gangliosides was calculated as a percent of total gangliosides, the brush-border membranes were enriched with GM3, GM1 and GD1a compared to the basolateral membranes, which were enriched with GD3 and GM4. The observation of a distinct distribution of glycolipids between brush-border and basolateral membranes of the same epithelial cell suggests that there may be a specific sorting and insertion process for epithelial plasma membrane glycolipids. In turn, asymmetric glycolipid biogenesis may reflect differences in glycolipid function between the two domains of the epithelial plasma membrane.
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Affiliation(s)
- S Spiegel
- Membrane Biochemistry Section, National Institute of Neurological and Communicative Disorders and Stroke, Bethesda, MD 20892
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91
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Hauri HP. Biogenesis and intracellular transport of intestinal brush border membrane hydrolases. Use of antibody probes and tissue culture. Subcell Biochem 1988; 12:155-219. [PMID: 3043766 DOI: 10.1007/978-1-4899-1681-5_5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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92
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Orci L, Ravazzola M, Amherdt M, Perrelet A, Powell SK, Quinn DL, Moore HP. The trans-most cisternae of the Golgi complex: a compartment for sorting of secretory and plasma membrane proteins. Cell 1987; 51:1039-51. [PMID: 2826013 DOI: 10.1016/0092-8674(87)90590-3] [Citation(s) in RCA: 238] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The intracellular site for the sorting of proteins destined for regulated or constitutive pathways is presently unknown for any one cell. By immunoelectron microscopy, we directly followed the routes taken by a regulated hormone, insulin, and a constitutive protein, hemagglutinin. Both proteins are present in individual Golgi stacks where they appear randomly distributed throughout the cisternae. In contrast, the two proteins do not colocalize outside the Golgi area:insulin is concentrated in dense-core secretory granules, while hemagglutinin is found predominantly in clear 100-300 nm vesicles. These vesicles do not label significantly with an endocytic tracer, indicating that they are exocytic carriers for hemagglutinin. The site at which the two proteins diverge is the clathrin-coated, trans-most cisterna of the Golgi, where the packaging of proinsulin takes place.
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Affiliation(s)
- L Orci
- Institute of Histology and Embrology, University of Geneva, Switzerland
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93
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Urban J, Parczyk K, Leutz A, Kayne M, Kondor-Koch C. Constitutive apical secretion of an 80-kD sulfated glycoprotein complex in the polarized epithelial Madin-Darby canine kidney cell line. J Biophys Biochem Cytol 1987; 105:2735-43. [PMID: 3693398 PMCID: PMC2114694 DOI: 10.1083/jcb.105.6.2735] [Citation(s) in RCA: 168] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The biosynthesis, processing, and apical secretion of a group of polypeptides (Kondor-Koch, C., R. Bravo, S. D. Fuller, D. Cutler, and H. Garoff. 1985. Cell. 43:297-306) are studied in MDCK cells using a specific polyclonal antiserum. These polypeptides are synthesized as a precursor protein which has an apparent Mr of 65,000 in its high mannose form. This precursor is converted into a protein with an apparent Mr of 80,000 containing complex carbohydrates and sulfate. After intracellular cleavage of the 80-kD protein, the 35-45-kD subunits are secreted as an 80-kD glycoprotein complex (gp 80) linked together by disulfide bonds. Secretion of the protein complex occurs by a constitutive pathway at the apical surface of the epithelial monolayer. Since the immediate post-translational precursor, the 65-kD protein, is hydrophilic in nature as shown by its partitioning behavior in a phase-separated Triton X-114 solution, gp 80 is segregated into the apical exocytotic pathway as a soluble molecule. The proteolytic maturation of gp 80 is blocked in the presence of chloroquine and its secretion is retarded. The 80-kD precursor is released at the apical cell surface, demonstrating that proteolytic processing is not necessary for the apical secretion of this protein. If N-glycosylation is inhibited by tunicamycin treatment the protein is secreted in equal amounts at both cell surfaces, indicating a role of the carbohydrate moieties in the vectorial transport of this protein.
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Affiliation(s)
- J Urban
- Abt. Molekulare Genetik, Universität Frankfurt, Federal Republic of Germany
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94
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Mostov KE, Breitfeld P, Harris JM. An anchor-minus form of the polymeric immunoglobulin receptor is secreted predominantly apically in Madin-Darby canine kidney cells. J Cell Biol 1987; 105:2031-6. [PMID: 3680369 PMCID: PMC2114864 DOI: 10.1083/jcb.105.5.2031] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The polymeric immunoglobulin receptor is expressed in a variety of polarized epithelial cells. Newly made receptor travels first to the basolateral surface. The receptor is then endocytosed, transported across the cell in vesicles, and exocytosed at the apical surface. We have now deleted the membrane spanning and cytoplasmic portions of the receptor by site-directed mutagenesis, thus converting the receptor to a secretory protein. When expressed in polarized Madin-Darby canine kidney (MDCK) cells the truncated protein is secreted at both surfaces, with a ratio of apical-to-basal secretion of 3.4. In contrast, when the exogenous secretory protein chicken lysozyme is expressed in these cells, it is released at both sides with a ratio of apical-to-basal secretion of 0.43. (Koder-Koch, C., R. Bravo, S. Fuller, D. Cutler, and H. Garoff, 1985, J. Cell Biol., 43:297-306). Lysozyme is thought to lack a signal that targets it to one surface or the other, and so its secretion may represent a default, bulk flow pathway to both surfaces. When compared with lysozyme, the truncated polymeric immunoglobulin receptor is preferentially secreted apically by a factor of 3.4:0.43 or 7.8. We suggest that the lumenal portion of the polymeric immunoglobulin receptor contains a signal that targets it to the apical surface.
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Affiliation(s)
- K E Mostov
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142
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95
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Butler E, Hardin J, Benson S. The role of lysyl oxidase and collagen crosslinking during sea urchin development. Exp Cell Res 1987; 173:174-82. [PMID: 2890532 DOI: 10.1016/0014-4827(87)90343-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Lysyl oxidase, the only enzyme involved in collagen crosslinking, is shown to be present in embryos of the sea urchin Strongylocentrotus purpuratus. The enzyme specific activity increases over six-fold during development, showing the greatest rise during gastrulation and prism larva formation. The enzyme is inhibited by the specific inhibitor, beta-aminoproprionitrile (BAPN). Continuous BAPN treatment of S. purpuratus and Lytechinus pictus embryos from late cleavage stages onward increases the amount of noncrosslinked collagen present in prism larvae. When BAPN is added at the 128- or 256-cell stage it causes developmental arrest at the mesenchyme blastula stage. Embryos can be maintained in the arrested state for at least 96 h and will resume normal development and morphogenesis following BAPN removal. If BAPN is added after the mesenchyme blastula stage, it has little adverse effect on development; consequently nonspecific toxic effects of the drug are unlikely. The results suggest that lysyl oxidase and collagen crosslinking play a vital role in primary mesenchyme migration, gastrulation, and morphogenesis during sea urchin development and indicate that BAPN may be very useful in studying the extracellular matrix-cell interactions at the cellular and molecular level.
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Affiliation(s)
- E Butler
- Department of Biological Sciences, California State University, Hayward 94542
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96
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Salas PJ, Vega-Salas DE, Rodriguez-Boulan E. Collagen receptors mediate early events in the attachment of epithelial (MDCK) cells. J Membr Biol 1987; 98:223-36. [PMID: 3681953 DOI: 10.1007/bf01871185] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Madin-Darby canine kidney (MDCK) cells kept in suspension culture for 12-15 hr displayed high-affinity binding sites for 125I-lathyritic (soluble) collagen (120,000/cell, KD = 30 nM) and preferred collagens types I and IV over laminin or fibronectin as substrates during the first hour of attachment. On the other hand, after 4 hr, attachment to all four substrates was equally efficient. Upon challenge with a collagen substrate, the high-affinity sites were rapidly recruited on it (T1/2 = 6 min). Their occupancy by soluble collagen triggered the exocytosis of a second large population of low-affinity collagen binding sites that included laminin and seems to be involved in a second cell-attachment mechanism. These results are compatible with a two-step model of MDCK cell attachment to the substrate: first, via high-affinity collagen binding sites, and second, via laminin of cellular origin.
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Affiliation(s)
- P J Salas
- Department of Cell Biology and Anatomy, Cornell University Medical College, New York, New York 10021
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97
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van Meer G, Stelzer EH, Wijnaendts-van-Resandt RW, Simons K. Sorting of sphingolipids in epithelial (Madin-Darby canine kidney) cells. J Biophys Biochem Cytol 1987; 105:1623-35. [PMID: 3667693 PMCID: PMC2114647 DOI: 10.1083/jcb.105.4.1623] [Citation(s) in RCA: 330] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
To study the intracellular transport of newly synthesized sphingolipids in epithelial cells we have used a fluorescent ceramide analog, N-6[7-nitro-2,1,3-benzoxadiazol-4-yl] aminocaproyl sphingosine (C6-NBD-ceramide; Lipsky, N. G., and R. E. Pagano, 1983, Proc. Natl. Acad. Sci. USA, 80:2608-2612) as a probe. This ceramide was readily taken up by filter-grown Madin-Darby canine kidney (MDCK) cells from liposomes at 0 degrees C. After penetration into the cell, the fluorescent probe accumulated in the Golgi area at temperatures between 0 and 20 degrees C. Chemical analysis showed that C6-NBD-ceramide was being converted into C6-NBD-sphingomyelin and C6-NBD-glucosyl-ceramide. An analysis of the fluorescence pattern after 1 h at 20 degrees C by means of a confocal scanning laser fluorescence microscope revealed that the fluorescent marker most likely concentrated in the Golgi complex itself. Little fluorescence was observed at the plasma membrane. Raising the temperature to 37 degrees C for 1 h resulted in intense plasma membrane staining and a loss of fluorescence from the Golgi complex. Addition of BSA to the apical medium cleared the fluorescence from the apical but not from the basolateral plasma membrane domain. The basolateral fluorescence could be depleted only by adding BSA to the basal side of a monolayer of MDCK cells grown on polycarbonate filters. We conclude that the fluorescent sphingomyelin and glucosylceramide were delivered from the Golgi complex to the plasma membrane where they accumulated in the external leaflet of the membrane bilayer. The results also demonstrated that the fatty acyl labeled lipids were unable to pass the tight junctions in either direction. Quantitation of the amount of NBD-lipids delivered to the apical and the basolateral plasma membranes during incubation for 1 h at 37 degrees C showed that the C6-NBD-glucosylceramide was two- to fourfold enriched on the apical as compared to the basolateral side, while C6-NBD-sphingomyelin was about equally distributed. Since the surface area of the apical plasma membrane is much smaller than that of the basolateral membrane, both lipids achieved a higher concentration on the apical surface. Altogether, our results suggest that the NBD-lipids are sorted in MDCK cells in a way similar to their natural counterparts.
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Affiliation(s)
- G van Meer
- European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany
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98
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Nichols GE, Shiraishi T, Allietta M, Tillack TW, Young WW. Polarity of the Forssman glycolipid in MDCK epithelial cells. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 930:154-66. [PMID: 3040119 DOI: 10.1016/0167-4889(87)90027-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To determine whether epithelial plasma membrane glycolipids are polarized in a manner analogous to membrane proteins, MDCK cells grown on permeable filters were analyzed for the expression of Forssman ceramide pentasaccharide, the major neutral glycolipid in these cells. In contrast to a recent report which described exclusive apical localization of the Forssman glycolipid (Hansson, G.C., Simons, K. and Van Meer, G. (1986) EMBO J. 5, 483-489), immunofluorescence and immunoelectron microscopic staining revealed the Forssman glycolipid on both the apical and basolateral surfaces of polarized cells. Immunoblots indicated that the Forssman antigen was detectable only on glycolipids and not on proteins. Analysis of metabolically labeled glycolipids released into the apical and basal culture medium, either as shed membrane vesicles or in budding viruses, also demonstrated the presence of the Forssman glycolipid on both apical and basolateral membranes of polarized cells. Quantitation of the released glycolipid indicated that the Forssman glycolipid was concentrated in the apical membrane. These results are consistent with previous reports which described quantitative enrichment of glycolipids in the apical domain of several epithelia.
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99
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Tooze J, Tooze SA, Fuller SD. Sorting of progeny coronavirus from condensed secretory proteins at the exit from the trans-Golgi network of AtT20 cells. J Cell Biol 1987; 105:1215-26. [PMID: 2821011 PMCID: PMC2114808 DOI: 10.1083/jcb.105.3.1215] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Murine hepatitis virus (strain A59), (MHV-A59) is a coronavirus that buds into pre-Golgi compartments and then exploits the exocytic pathway of the host cell to reach the exterior. The fibroblastic cells in which replication of this virus is usually studied have only a constitutive exocytic pathway that the virus uses. MHV-A59 also infects, albeit inefficiently, AtT20 cells, murine pituitary tumor cells with a regulated as well as a constitutive exocytic pathway. Here we examine AtT20 cells at early times after the infection, when the Golgi apparatus retains its morphological and biochemical integrity. We observe that progeny coronavirus and secretory protein destined for the secretory granules of the regulated exocytic pathway traverse the same Golgi stacks and accumulate in the trans-Golgi network. Their pathways diverge at this site, the condensed secretory proteins including the ACTH going to the secretory granules and the coronavirus to post-Golgi transport vesicles devoid of ACTH. On very rare occasions there is missorting such that aggregates of condensed secretory proteins and viruses occur together in post-Golgi vesicles. We conclude that the constitutive and regulated exocytic pathways, identified respectively by the progeny virions and the secretory protein ACTH, diverge at the exit from the trans-Golgi network.
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Affiliation(s)
- J Tooze
- European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany
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100
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Heth CA, Yankauckas MA, Adamian M, Edwards RB. Characterization of retinal pigment epithelial cells cultured on microporous filters. Curr Eye Res 1987; 6:1007-19. [PMID: 3311644 DOI: 10.3109/02713688709034872] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Retinal pigment epithelium (RPE) cultured on microporous filter supports was compared to RPE cultured on plastic and evaluated for features characteristic of RPE in vivo. RPE cells grown on filters were cuboidal, formed junctional complex structures between cells, and had elaborate microvilli and basal infoldings similar to RPE in vivo, while RPE grown on plastic also formed intercellular junctions but appeared squamous and had few microvilli and basal infoldings. RPE grown on filters or plastic secreted an extracellular matrix at the basal surface and ingested isolated rat rod outer segments at the apical surface. RPE grown on filters coated with laminin or fibronectin became confluent more rapidly than RPE grown on uncoated filters, while RPE grown at the same density on filters coated with collagen type I did not become confluent. The laminin and fibronectin coatings did not alter the RPE cell morphology; however, cells seeded on collagen-coated filters grew in large disorganized clusters. RPE grown on laminin-coated filters formed functional tight junctions as evidenced by the capacity of RPE monolayers to prevent the bulk flow of medium and the passage of trypan blue across the filter. Radiolabeled sucrose and inulin were used to measure the paracellular flux through the tight junctions between cells. The passage of these tracers was linear over time, with the lower molecular weight tracer, sucrose, passing through the monolayer more readily than inulin. Values for the flux of radiolabeled bovine serum albumin across RPE monolayers fell between values for sucrose and inulin. The results from these studies show that RPE monolayers cultured on laminin-coated filters maintain a morphology similar to that of RPE in vivo, are capable of ingesting rod outer segments, and form a selectively permeable barrier to various tracers. This culture system should be useful for studies of transepithelial transport, secretion, endocytosis and exocytosis that require independent control of the extracellular environment at the apical and basolateral cell surfaces.
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Affiliation(s)
- C A Heth
- Berman-Gund Laboratory for the Study of Retinal Degenerations, Department of Ophthalmology, Harvard Medical School, Boston 02114
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