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Cited by 513Barrier Structure and Function StudiesCellular Mechanics and InteractionsCell Adhesion Molecules Research

The subcellular organization of Madin-Darby canine kidney cells during the formation of a polarized epithelium

Open access
Bacallao, R, Antony, C, Dotti, C, Karsenti, E, Stelzer, E H, Simons, K·1989·The Journal of cell biology
DOI 10.1083/jcb.109.6.2817PMC PMC2115929
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Abstract

Studies of the developing trophectoderm in the mouse embryo have shown that extensive cellular remodeling occurs during epithelial formation. In this investigation, confocal immunofluorescence microscopy is used to examine the three-dimensional changes in cellular architecture that take place during the polarization of a terminally differentiated epithelial cell line. Madin-Darby canine kidney cells were plated at a low density on permeable filter supports. Antibodies that specifically recognize components of the tight junction, adherens junction, microtubules, centrosomes, and the Golgi complex were used to study the spatial remodeling of the cytoarchitecture during the formation of the polarized cell layer. The immunofluorescence data were correlated with establishment of functional tight junctions as measured by transepithelial resistance and back-exchange of the cell surface, labeled with metabolites of the fluorescent lipid analogue N-(7-[4-nitrobenzo-2-oxa-1,3-diazole]) aminocaproyl sphingosine. 1 d after plating, single cells had microtubules, radiating from a broad region, that contained the centrosomes and the Golgi complex. 2 d after plating, the cells had grown to confluence and had formed functional tight junctions close to the substratum. The centrioles had split and no longer organized the microtubules which were running above and below the nucleus. The Golgi complex had spread around the nucleus. By the fifth day after plating, the final polarized state had been achieved. The junctional complex had moved greater than 10 microns upward from its basal location. The centrioles were together below the apical membrane, and the Golgi complex formed a ribbon-like convoluted structure located in the apical region above the nucleus. The microtubules were organized in an apical web and in longitudinal microtubule bundles in the apical-basal axis of the columnar cell. The longitudinal microtubules were arranged with their minus ends spread over the apical region of the cell and their plus ends toward the basal region. These findings show that there is an extensive remodeling of epithelial cytoarchitecture after formation of cell-cell contacts. Reorganization of the microtubule network results in functional polarization of the cytoplasm.

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Written from the paper’s full text.

TL;DR

Confocal immunofluorescence and functional assays show that MDCK strain II cells undergo coordinated remodeling of microtubules, centrosomes, Golgi complex, and junctions as they form a polarized epithelium on permeable filters. In the final columnar state, the junctional complex moves upward >10 µm, centrioles and Golgi relocate apically, and longitudinal microtubules are oriented with plus ends basal.

Key findings

  • 1 d after plating, 86% of cells had a single microtubule-organizing complex with centrioles together and colocalized; 14% lacked a single nucleating center. The Golgi complex was compact and perinuclear.
  • 2 d after plating, cells reached confluence and developed transepithelial resistance of 20–40 Ω·cm²; tight junctions formed close to the substratum, centrioles split, microtubules formed a crisscrossed apical network, and the Golgi complex spread around the nucleus. C6-NBD-ceramide back-exchange showed the tight-junction lipid fence was already operating.
  • By 5 d, cells were columnar, 15–18 µm high; the junctional complex had moved >10 µm upward, centrioles were together below the apical membrane, and the Golgi complex formed a ribbon-like convoluted apical structure above the nucleus.
  • Microtubule polarity by the hook method: plus ends were basal in 90.9% of basal sections, 90.6% of middle sections, and 85.2% of apical sections; apical microtubules running parallel to the apical membrane showed clockwise and counterclockwise hooks in equal proportions, suggesting no unique apical nucleating center.

Methods

  • MDCK strain II cells were plated at low density on polycarbonate filter supports (Transwell, 0.4-µm pore) and followed from single cells to the polarized monolayer.
  • Confocal immunofluorescence microscopy used antibodies against tubulin, ZO-1, uvomorulin, Golgi complex protein (M3A5), and centrosomes (45H3); functional assays included transepithelial resistance and C6-NBD-ceramide labeling with BSA back-exchange.
  • Microtubule polarity was determined by the hook method after detergent permeabilization or electroporation; serial optical sections (0.4 µm thick, 512 × 512 pixels) were used for three-dimensional reconstruction and stereo imaging.

Limitations

  • Stated: whether MDCK cells have a single interconnected Golgi complex “has to await an ultrastructural analysis”; the structures that nucleate apical microtubules were not identified; whether microtubule plus ends remain free or attach to basal structures is not known; and more work is needed to define exocytic traffic and microtubule roles in epithelial polarity.
  • Stated/evident: some supporting observations are unpublished (e.g., cold/nocodazole depolymerization and regrowth from apical foci; Golgi fragmentation after microtubule depolymerization), and detergent extraction altered apical ultrastructure, requiring electroporation for confirmation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1083/jcb.109.6.2817

Cites

54 of 54 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 55 cited sources checked · 0 supported · 0 flagged

  • Findingown data
    § Results

    1 d after plating, all the cells had spread upon the filter support.

    “1 d after plating, all the cells had spread upon the filter sup- port.”
    Quote in the paperNot a substantial claim
  • Findingown data
    § Abstract

    1 d after plating, single cells had microtubules radiating from a broad region that contained the centrosomes and the Golgi complex.

    “1 d after plating, single cells had microtubules, radiating from a broad region, that contained the centrosomes and the Golgi complex.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Results

    In 5-day cells, the microtubule staining pattern inside cells appeared as dots or fibers parallel to the apical-basal axis.

    “Inside the cells, the microtubule staining pattern appeared as dots or fibers parallel to the apical-basal axis.”
    Quote in the paperNot a substantial claim
  • Findingown data
    § Abstract

    By the fifth day after plating, the microtubules were organized in an apical web and in longitudinal microtubule bundles in the apical-basal axis of the columnar cell.

    “The microtubules were organized in an apical web and in longitudinal microtubule bundles in the apical-basal axis of the columnar cell.”
    Quote in the paperSubstantial claim
  • Findingown data
    § Abstract

    2 d after plating, the Golgi complex had spread around the nucleus.

    “The Golgi complex had spread around the nucleus.”
    Quote in the paperNot a substantial claim
  • May combine two claims. 26
  • The quote only partly states this claim. 6
  • Classified as probably not a substantial claim. 39

  • May combine two claims.

    Findingown data
    § Results

    2 d after plating, MDCK cells established intercellular contacts and developed a transepithelial resistance ranging between 20 and 40 Ω·cm2.

    “2 d after plating, the cells established intercellular con- tacts, and a transepithelial resistance, ranging between 20 and 40 fl.cm2developed.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    In cells with a single microtubule-organizing complex, the two centrioles were close to each other, near the nucleus, and localized in the region from where microtubules originated.

    “In these cells, the two centri- oles were close to each other, near the nucleus, and localized in the region from where microtubules originated.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    In the first series of hook experiments, four out of five microtubules in a section parallel to the filter plane showed right-handed hooks, and the fifth had an equivocal orientation.

    “Four out of five microtubules found in this section showed right-handed hooks. The fifth microtubule (Fig. 5 A) exhibited an equivocal orientation.”
    Quote in the paperSubstantial claim

  • The quote only partly states this claim.

    Findingown data
    § Results

    A similar hook pattern was observed throughout the entire central region of the cells.

    “A similar pattern was observed throughout the entire central region of the cells.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Results

    On the fifth day of growth, MDCK cells were columnar and 15-18 μm high.

    “On the fifth day of growth, the cells were columnar, 15-18 #m high.”
    Quote in the paperNot a substantial claim

  • May combine two claims. The quote only partly states this claim.

    Findingown data
    § Results

    After removing the first seven apical optical sections, microtubule bundles ran down along cell borders and splayed into the basal domain, forming a sparse network in most cells.

    “The microtubule bundles are running down along the cell borders and splay into the basal domain where they form a sparse network in most ceils.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data
    § Results

    Most of the cells were isolated and had a flattened cytoplasmic region.

    “Most of the cells were isolated and had a flattened cyto- plasmic region.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    2 d after plating, the cells had grown to confluence and had formed functional tight junctions close to the substratum.

    “2 d after plating, the cells had grown to confluence and had formed functional tight junctions close to the substratum.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given
    § Introduction

    In fully polarized cells, microtubules are arranged in vertical bundles with their plus ends facing the basal domain.

    “In fully polarized cells, microtubules are arranged in vertical bun- dles with their plus ends facing the basal domain.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Abstract

    2 d after plating, the centrioles had split and no longer organized the microtubules running above and below the nucleus.

    “The centrioles had split and no longer organized the microtubules which were running above and below the nucleus.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Results

    The nucleus was centrally located, and the maximal height of the cells was 4-6 μm at the level of the nucleus.

    “The nucleus was centrally located, and the maximal height of the cells was 4-6/zm at the level of the nucleus (Fig. 1 A).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    At 2 d after plating, although some cells had microtubules originating from a localized perinuclear region, most cells had microtubules forming a crisscrossed apical network that did not appear to originate from a single nucleating center.

    “Although in some cells microtubules were still originating from a localized perinuclear region (Fig. 2 A, arrow), in most cases they formed a crisscrossed apical network and did not appear to originate from a single nucleating center (Fig. 2, A and B).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given
    § Introduction

    In fully polarized cells, the Golgi complex is located in the apical-most region of the cell close to the minus ends of the vertical microtubules.

    “The Golgi complex is located in the apical-most region of the cell close to the minus ends of the vertical microtubules.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data
    § Results

    90% of decorated microtubules in horizontal sections had hooks with a clockwise orientation.

    “As shown in Table HI, 90% of the decorated microtubules had hooks with a clockwise orientation.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Results

    At 2 d after plating, the long axis of MDCK cells was still parallel to the substratum, and cell height varied between 6 and 10 μm at the level of the nucleus.

    “The long axis of the cell was still parallel to the substratum, and the height of the cells varied between 6 and 10 #m at the level of the nucleus.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingcitation
    § Results

    On the fifth day, stereo images showed a complex microtubule pattern with cilia present in almost all cells.

    “Stereo images showed a complex microtubule pat- tern with the presence of cilia (Roth et al., 1988) in almost all of the cells (Fig. 3 A).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Roth et al., 1988

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    Findingnone given
    § Discussion

    We have not identified the structures from which microtubules could be nucleated in the apical domain in MDCK cells.

    “We have not identified the struc- tures from which microtubules could be nucleated in the api- cal domain in MDCK cells.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Discussion

    Once a confluent monolayer is formed, cells begin to change shapes, and tight junctions move upward >10 μm to circumscribe the apex of each columnar cell.

    “Once a confluent monolayer is formed, the cells begin to change their shapes. The tightjunctions that originallyformed close to the substratum move upward >I0 ~m to circum- scribe the apex of each columnar cell in the final”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing), S4 (based). May combine two claims.

    Findingnone given
    § Discussion

    The 'worm-like' structure of the MDCK Golgi complex is fragmented after microtubule depolymerization and disperses in the apical part of the cell.

    “The”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    By 3 d after plating, cells began to show a polygonal shape, and the Golgi complex was spread around the nucleus; in some cells, the Golgi complex began to migrate above the nucleus.

    “By 3 d, the cells began to show a polygonal shape, and the Golgi complex was spread around the nucleus. In some cells, the Golgi complex began to migrate above the nucleus (Fig. 8 B).”
    Quote in the paperSubstantial claim

  • The quote only partly states this claim.

    Findingown data
    § Results

    In isolated cells 1 d after plating, most microtubules seemed to originate from the region around the centrioles.

    “Most microtubules seemed to originate from this region (Fig. 1 B and Tables I and II).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Results

    In some cells at 2 d after plating, the Golgi complex began to spread around the nucleus, and these cells appeared more fusiform with microtubules that did not radiate from the perinuclear area.

    “In some cells, the Golgi complex began to spread around the nucleus. These cells appeared more fusiform and their microtubules did not radiate from the perinuclear area (Fig. 2 B).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Discussion

    Microtubule bundles have formed and are parallel to the apical-basal axis of the cell.

    “Microtubule bundles have formed and these are parallel to the apical-basal axis of the cell.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingnone given
    § Discussion

    The final location of the two centrioles is in close apposition to the apical membrane, where they do not nucleate many microtubules.

    “The final location of the two centrioles is in close apposition to the apical membrane where they do not nucleate many microtubules.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data
    § Results

    At 1 d after plating, uvomorulin and ZO-1 staining were observed intracellularly.

    “At this stage, uvomorulin and ZO-1 staining were observed intracellularly (data not shown).”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data
    § Results

    In 5-d-old cells, basal application of BSA completely removed the lateral staining up to the apical membrane.

    “Basal application of BSA completely removed the lateral staining of the cells up to the apical mem- brane (Fig. 10 B).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation
    § Introduction

    Newly synthesized apical and basolateral components are sorted in the trans-Golgi network into carrier vesicles.

    “Newly synthesized apical and basolateral componentsare sorted in the trans-Golginet- work into carrier vesicles (Griffiths and Simons, 1986; Ben- nett et al., 1988).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Griffiths and Simons, 1986

      Not checked in the free run.

    • cites Bennett et al., 1988

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    Premisecitation
    § Introduction

    The Golgi complex is usually positioned above the nucleus in the apical part of the epithelial cell.

    “It is usually positioned above the nucleus in the apical part of the epithelial cell (Cajal, 1914).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Cajal, 1914

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    Premisecitation
    § Introduction

    The bipolar structure is further modified by lateral interactions between adjacent cells mediated by cell adhesion and junctional proteins.

    “The bipolar structure is further modified by lateral interactions between adjacent cells mediated by cell adhesion andjunctional proteins (Duci- bella and Anderson, 1975; Gumbiner et al., 1988).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Ducibella and Anderson, 1975

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    • cites Gumbiner et al., 1988

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    Premisecitation
    § Introduction

    Confocal microscopy offers the advantage of increased resolution and out-of-depth focus discrimination.

    “Confocal microscopy offers the advantage of in- creased resolution and out-of-depth focus discrimination.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Stelzer et al., 1989

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § Introduction

    Protein-protein interactions lead to the formation of circumferential tight junctions that seal the cell layers and divide the epithelial cell surface into apical and basolateral cell surface domains.

    “These protein-protein interactions lead to the formation of circum- ferentialtightjunctions that seal the cell layers and dividethe epithelial cell surface into apical and basolateral cell surface domains (Gumbiner, 1987).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Gumbiner, 1987

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    Study design and conductown data
    § Materials and Methods

    Prior experiments showed there was no loss of three-dimensional information when the specimens were stored as described.

    “Prior experiments showed there was no loss of three-dimensional information when the specimens were stored as described above.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Introduction

    In fibroblasts, microtubules are organized by the centrosome in the vicinity of the nucleus.

    “In some cell types, such as fibroblasts, microtubulesare organized by the centrosomein the vicinity of the nucleus (Singer and Kupfer, 1986).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Singer and Kupfer, 1986

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    Premisecitation
    § Introduction

    The interaction between the microtubule-organizing complex and the Golgi complex is dynamic and involves active movement of Golgi elements towards the minus ends of centrosome-nucleated microtubules.

    “This interaction is dynamic and in- volvesactive movement of Golgi elements towards the minus ends of centrosome-nucleated microtubules (Thyberg and Moskalewski, 1985; Kupfer et al., 1986; Ho et al., 1989).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Thyberg and Moskalewski, 1985

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    • cites Kupfer et al., 1986

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    • cites Ho et al., 1989

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    Interpretationown data
    § Results

    The maximal height of the cells at the level of the nucleus corresponded to the approximate diameter of the nucleus.

    “This height corresponded to the approxi- mate diameter of the nucleus.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Introduction

    The Golgi complex plays an important role in the targeting and delivery of newly synthesized plasma membrane components.

    “The Gol- gi complex plays an important role in this process (Grifiiths and Simons, 1986; Wandinger-Ness and Simons, 1989).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Grifiiths and Simons, 1986

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    • cites Wandinger-Ness and Simons, 1989

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    Premisecitation
    § Introduction

    The apical pole is generated on the opposite side of the cell by little understood alterations of the intracellular organization.

    “Subsequently, the apical pole is generatedon the opposite side ofthe cell by little understood alterations of the intracellular organization (Johnson and Maro, 1985; Vega-Salas et al., 1987).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Johnson and Maro, 1985

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    • cites Vega-Salas et al., 1987

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    Premisecitation
    § Introduction

    The delivery of carrier vesicles to the apical plasma membrane seems to be mediated by microtubules.

    “The delivery of these carder vesicles to the apical plasma membrane seems to be mediatedby micro- tubules (Quaroni et al., 1979; Rindler et al., 1987; Achier et al., 1989; Eilers et al., 1989).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Quaroni et al., 1979

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    • cites Rindler et al., 1987

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    • cites Achier et al., 1989

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    Premisecitation
    § Discussion

    Apical and basolateral components present on the wrong side of the fence have to be removed either by transcytosis to the correct domain or by degradation.

    “Apical and basolateral components present on the wrong side of the fence have to be removed either by transcytosis to the correct domain or by degradation (Peso- nen et al., 1984a,b; Cereijido et al., 1989).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Peson-en et al., 1984a,b

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    Interpretationown data
    § Discussion

    2 d after plating, MDCK cells reach confluence and microtubules are not nucleated by a single microtubule-organizing complex any longer.

    “2 d after plating, the MDCK cells reach conflueney and the microtubules are not nucleated by~asingle microtubule- organizing complex any longer.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § Discussion

    Newt neural epithelial cells are columnar cells of enormous height (~100 μm) and have long microtubules oriented from apex to base.

    “The newt neural epi- thelial cells are columnar cells of enormous height (,x,100 ~m) and have long microtubules oriented from the apex to the base.”
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    • cites Burnside, 1971

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    Premisecitation
    § Discussion

    In other cell types, the structure of the Golgi complex is linked to microtubule organization.

    “Also, in other cell types, the structure of the Golgi complex is linked to microtubule organization (Thyberg and Moskalewski, 1985).”
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    • cites Thyberg and Moskalewski, 1985

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    Premisecitation
    § Discussion

    In fibroblasts, dispersed Golgi elements recluster after microtubule repolymerization from the microtubule-organizing complex.

    “In fibroblasts, the dis- persed Golgi elements recluster after microtubule repolymer- ization from the microtubule-organizing complex (Rogalski and Singer, 1984).”
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    • cites Rogalski and Singer, 1984

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    Premisecitation
    § Discussion

    There is only one interconnected Golgi complex in each cell type studied.

    “The studies of Rambourg et al. (1981, 1987) have demonstrated that there is only one interconnected Golgi complex in each cell type studied.”
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    • cites Rambourg et al. (1981, 1987)

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    Premisecitation
    § Discussion

    Longitudinal bundles running in the apical-basal direction have been observed previously in intestinal epithelium and during newt neurulation.

    “Longitudinal bundles running in the apical-basal direction have been observed previously in in- testinal epithelium (Gorbsky and Borisy, 1985; Achier et al., 1989) as well as during the development of the neural tube in newt neurulation (Burnside, 1971).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Gorbsky and Borisy, 1985

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    • cites Achier et al., 1989

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    • cites Burnside, 1971

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    Premisenone given
    § Discussion

    In these cells (newt, Drosophila), microtubules are not nucleated by centrosomes; instead, they are fixed to the plasma membrane on apical and basal sides by electron-dense attachment sites.

    “The microtubules in these cells are not nucleated by centrosomes. Instead, they are fixed to the plasma membrane on the apical and the basal sides by electron-dense attachment sites.”
    Quote in the paperNot a substantial claim

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    Premisecitation
    § Discussion

    During Drosophila wing development, similar microtubular arrays are formed in the long axis of epidermal cells.

    “Also, during Drosophila wing development, simi- lar microtubular arrays are formed in the long axis of the epidermal cells (Tucker et al., 1986).”
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    • cites Tucker et al., 1986

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    Premisecitation
    § Discussion

    When myoblasts fuse to form myotubes, the microtubule-nucleating activity changes from a centrosomal location to a circumnuclear distribution, and the Golgi complex spreads from its position around the centrosome to a location surrounding the nucleus.

    “Another example of Golgi movement during differentiation is ob- served when myoblasts fuse to form myotubes (Tassin et al. 1985a,b). The microtubule-nucleatingactivitychanges from a centrosomal location to a circumnuclear distribution. Con- comitantly, the Golgi complex spreads from its position around the centrosome in myoblasts to a location surround- ing the nucleus in the myotubes.”
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    • cites Tassin et al. 1985a,b

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    Premisecitation
    § Discussion

    In Sertoli cells, the Golgi complex forms a wavy ribbon- or plate-like structure that winds from the top of the nucleus to the apex of the cell.

    “In these cells, the Golgi complex forms a wavyribbon- or plate- like structure that winds from the top of the nucleus to the apex of the cell.”
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    • cites Rambourg et al., 1979

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    Premisecitation
    § Discussion

    Golgi elements move along microtubules towards their minus ends.

    “The Golgi elements move along microtu- bules towards their minus ends (Ho et al., 1989).”
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    • cites Ho et al., 1989

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    Interpretationown data
    § Results

    The centrioles split and move apically during the establishment of epithelial cell polarity.

    “From this data and electron microscopy data, we conclude that the centrioles split and move apically during the establishment of epithelial cell polarity.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation
    § Discussion

    The final state of the Golgi complex in MDCK cells is reminiscent of the three-dimensional structure of the Golgi complex in Sertoli cells.

    “The final state of the Golgi complex in MDCK cells is reminiscent of the three-dimensional structure of the Golgi complex in Sertoli cells (Rambourg et al., 1979).”
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    • cites Rambourg et al., 1979

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    Premisecitation
    § Results

    Previous work has shown that in subconfluent MDCK strain II cells grown on glass, the two centrioles are separated.

    “Previous work has shown that in subconfiuent MDCK strain II cells grown on glass the two centrioles are separated (Br~ et al., 1987).”
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    • cites Br~ et al., 1987

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    Premisecitation
    § Discussion

    Development of cell surface polarity is known to continue after tight junctions have been formed.

    “The develomentof cell surface polar- ity is known to continue after the tight junctions have been formed (Balcarova-Stfinder et al., 1984; Herzlinger and Ojakian, 1984).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Balcarova-Stfinder et al., 1984

      Not checked in the free run.

    • cites Herzlinger and Ojakian, 1984

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The Golgi complex moves basally exactly at the time when the primary stroma and Bowman's membrane are assembled beneath the basolateral plasma membrane of the corneal epithelium.

    “Trelstad (1970) has shown that the Golgi com- plex moves basally exactly at the time when the primary stroma and Bowman's membrane are assembled beneath the basolateral plasma membrane of the corneal epithelium.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Trelstad (1970)

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In other epithelial cells, intact microtubules are necessary for facilitating delivery in the apical direction.

    “In other epithelial cells it seems likely that intact microtubules are necessary for facilitating delivery in the apical direction (Eilers et al., 1989; Achier et al., 1989).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Eilers et al., 1989

      Not checked in the free run.

    • cites Achier et al., 1989

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The rate of delivery to the unpolarized cell surface is unchanged or decreased by ~50% after microtubule depolymerization.

    “However, the rate of delivery to the unpo- larized cell surface is unchanged or decreased by ,~50% (IG~xi~iinen et al., 1980; Rogalski et al., 1984).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites IG~xi~iinen et al., 1980

      Not checked in the free run.

    • cites Rogalski et al., 1984

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In the mouse embryo, ZO-1 is initially organized in spots along the perimeter of the cells.

    “In the mouse embryo, the ZO-1 protein is initially organized in spots along the perimeter of the cells and assembles into zonular tight junctions at the 16-32-cell stage (Fleming et al., 1989).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Fleming et al., 1989

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In the mouse embryo, ZO-1 assembles into zonular tight junctions at the 16-32-cell stage.

    “In the mouse embryo, the ZO-1 protein is initially organized in spots along the perimeter of the cells and assembles into zonular tight junctions at the 16-32-cell stage (Fleming et al., 1989).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Fleming et al., 1989

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Discussion

    Up to the early eight-cell stage, the blastomere is organized in a symmetrical fashion except for the region of cell-cell contact.

    “Up to the early eight-cell stage, the blastomere is organized in a symmetrical fashion except for the region of cell-cell contact.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Fleming and Johnson, 1988

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Pericentriolar material has been detected in the apical part of the cell using an autoantibody against human centrosomes.

    “There is no centrosome at this stage, but pericentriolar material has been detected in the ap- ical part of the cell using an autoantibody against human cen- trosomes (Houliston et al., 1987).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Houliston et al., 1987

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Intercellular interactions in the blastomere lead to the establishment of the apical-basal axis.

    “These in- tercellular interactions are mediated by uvomorulin (Vest- weber et al., 1987) and lead to the establishment of the api- cal-basal axis.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Vestweber et al., 1987

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    After microtubule depolymerization, polarized exocytosis in fibroblasts is abolished.

    “After microtubule depolymeriza- tion, polarized exocytosis in fibroblasts is abolished (Rogal- ski et al., 1984).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rogalski et al., 1984

      Not checked in the free run.

63 of 63

  • The authors state this as an assumption.

    Microtubule organization contributes to the development of epithelial polarity.

    “One would, therefore, as- sume that microtubule organization contributes to the devel- opment of epithelial polarity.”

  • The paper relies on this without support.

    The precise organization and polarity of microtubules in epithelial cells are not known.

    “However, the precise organization and the polarity of the microtubules are not known.”

  • The paper relies on this without support.

    The relation of microtubule organization to the location of the Golgi complex is not clear.

    “The relation of microtubule organization to the location ofthe Golgi com- plex is also not clear.”

  • The paper relies on this without support.

    During the eight-cell stage, microtubules redistribute to generate a highly concentrated meshwork underlying the developing apical pole.

    “During the eight-cell stage, the microtubules redis- tribute to generate a highly concentrated meshwork underly- ing the developing apical pole.”

  • The paper relies on this without support.

    There is no centrosome at the eight-cell stage.

    “There is no centrosome at this stage”

  • The paper relies on this without support.

    In contrast to MDCK cells, the Golgi complex is located basally below the nucleus at the 16-cell stage.

    “However, in contrast to MDCK cells, the Golgi complex is located basally below the nucleus at the 16-cell stage.”

  • The paper relies on this without support.

    When microtubules are depolymerized by drugs, apical transport from the Golgi complex is decreased.

    “When microtubules are depolymerized by drugs, apical.transport from the Golgi complex is decreased.”

  • The paper relies on this without support.

    In a similar manner, the ZO-1 protein assembles at the edges of contacting MDCK cells.

    “In a similar manner, the ZO-1 protein assembles at the edges of contacting MDCK cells.”

  • The paper relies on this without support.

    The cell surface polarizes and a basal pole is defined by contact to adjacent cells.

    “The cell surface polarizes and a basal pole is defined by contact to adjacent cells.”
9 of 9

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Centrioles are described as colocalized in all cells with a single organizing complex

    Minor

    The prose says the centrioles in the 86% of cells with this microtubule pattern were located where the microtubules originated. Table I instead reports that 14 of those 86 cells had centrioles that did not colocalize with the organizing complex.

1 of 1

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Authors
Bacallao, R., Antony, C., Dotti, C., Karsenti, E., Stelzer, E. H., & Simons, K.
Affiliations
European Molecular Biology Laboratory (DE)
ORCID
Venue
The Journal of cell biology
Publisher
Rockefeller University Press
Published
1989-12-01
Volume
109
Issue
6
Pages
2817-2832
ISSN
  • 0021-9525 (ISSN-L)
  • 1540-8140
DOI
10.1083/jcb.109.6.2817
PMC
PMC2115929
OpenAlex
W2046560218
Semantic Scholar
01a37739aa7fd42e2986c3bc32807b3192a299bb
Cited by
513
References
54
Citations by year
2026: 3 · 2025: 8 · 2024: 6 · 2023: 6 · 2022: 6 · 2021: 9 · 2020: 6 · 2019: 12 · 2018: 8 · 2017: 14 · 2016: 9 · 2015: 12 · 2014: 9 · 2013: 15 · 2012: 21
FWCI
13.54
Type
journal article
Language
en
Open access
Licence
cc-by-nc-sa
Locations
  • The Journal of Cell Biology (publishedVersion)
  • PubMed Central (publishedVersion, cc-by-nc-sa)
  • PubMed (publishedVersion)
Funders
National Institute of Diabetes and Digestive and Kidney Diseases (DK01777)
Topics
  • Life Sciences › Neuroscience › Neurology › Barrier Structure and Function Studies
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Cellular Mechanics and Interactions
  • Health Sciences › Medicine › Immunology and Allergy › Cell Adhesion Molecules Research
Keywords
epithelial polarization, MDCK cells, tight junctions, adherens junctions, microtubule organization, centrosome, Golgi apparatus, transepithelial electrical resistance, cell-cell contact
MeSH terms
Animals, Antibodies, Cell Line, Dogs, Epithelium, Golgi Apparatus, Immunohistochemistry, Kidney, Membrane Potentials, Microscopy, Electron, Microscopy, Fluorescence, Microtubules, Subcellular Fractions, Organelles

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Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-09.

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