Knockdown of occludin expression leads to diverse phenotypic alterations in epithelial cells.

  title={Knockdown of occludin expression leads to diverse phenotypic alterations in epithelial cells.},
  author={Alan S. L. Yu and Karin M McCarthy and Stacy A Francis and Joanne M. McCormack and J Lai and Rick A. Rogers and Robert D. Lynch and Eveline E. Schneeberger},
  journal={American journal of physiology. Cell physiology},
  volume={288 6},
The function of occludin (Occ) in the tight junction is undefined. To gain insight into its role in epithelial cell biology, occludin levels in Madin-Darby canine kidney II cells were suppressed by stably expressing short interfering RNA. Suppression of occludin was associated with a decrease in claudins-1 and -7 and an increase in claudins-3 and -4. Claudin-2 levels were unaffected. The tight junction "fence" function was not impaired in suppressed Occ (Occ-) clones, as determined by BODIPY… 

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Roles of ZO-1, occludin, and actin in oxidant-induced barrier disruption.

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Clues to occludin. Focus on "Knockdown of occludin expression leads to diverse phenotypic alterations in epithelial cells".

  • K. Matlin
  • Biology
    American journal of physiology. Cell physiology
  • 2005
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Occludin, a transmembrane (TM)-spanning protein, is an integral component of the tight junctional (TJ) complexes that regulate epithelial integrity and paracellular barrier function. However, the

Cell confluence regulates claudin-2 expression: possible role for ZO-1 and Rac.

It is shown that Cldn-2 protein and mRNA expression were low in subconfluent tubular cells and increased during junction maturation, and that TJ integrity and maturity, ZO-1 expression/TJ localization, and Rac/Pak control CldN-2 degradation and synthesis.

Inflammation-induced Occludin Downregulation Limits Epithelial Apoptosis by Suppressing Caspase 3 Expression.

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ZO-1 function in the assembly of tight junctions in MDCK epithelial cells

It is shown that gene silencing of ZO-1 causes a delay of ~3 hours in tight junction formation in MDCK epithelial cells, but mature junctions appear functionally normal even in the continuing absence of Z o-1, and an unexpected function for the SH3 domain of Zo-1 is revealed in regulating tight junction assembly in epithelia.



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Occludin-deficient Embryonic Stem Cells Can Differentiate into Polarized Epithelial Cells Bearing Tight Junctions

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Occludin is a functional component of the tight junction.

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Role of tyrosine phosphorylation in the reassembly of occludin and other tight junction proteins.

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Nonreceptor tyrosine kinase c-Yes interacts with occludin during tight junction formation in canine kidney epithelial cells.

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Conversion of Zonulae Occludentes from Tight to Leaky Strand Type by Introducing Claudin-2 into Madin-Darby Canine Kidney I Cells

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Claudin-8 Expression in Madin-Darby Canine Kidney Cells Augments the Paracellular Barrier to Cation Permeation*