Tight junction proteins occludin

Figure 11.2 Morphological differences between human alveolar epithelial cells in primary culture (A and C) and the A549 cell line (B and D). Cells are visualised by light microscopy (A and B) and immunofluorescence microscopy (C and D) using an antibody against a tight junctional protein, occludin.

Nusrat A, Brown GT, Tom J, Drake A, Bui TTT, Quan C, and Mrsny RJ [2005] Multiple protein interactions involving proposed extracellular loop domains of the tight junction protein occludin. Mol Biol Cell 16 1725-1734... 

Lehmann AD, Blank F, Baum O et al (2009) Diesel exhaust particles modulate the tight junction protein occludin in lung cells in vitro. Part Fibre Toxicol 6 26... 

Figure 1 Astrocytes make close contact with endothelial cells within the retina. (A) Immunostaining for the tight junction protein occludin reveals a high degree of well-organized tight junctions in the arterioles and capillaries of the retina. (B) Glial fibrillary acid protein staining demonstrates that astrocytes make close contact with the endothelial cells within the retina.

Mankertz J, Waller JS, Hillenbrand B, et al. Gene expression of the tight junction protein occludin includes differential splicing and alternative promoter usage. Biochem Biophys Res Commun 2002 298 657-666. 

Antonetti DA, Barber AJ, Hollinger LA, Wolpert EB, Gardner TW. Vascular endothelial growth factor induces rapid phosphorylation of tight junction proteins occludin and zonula occluden 1. A potential mechanism for vascular permeability in diabetic retinopathy and tumors. J Biol Chem 1999 274 23,463-23,467. 

Stelwagen K, McFadden HA, Demmer J. Prolactin, alone or in combination with glucocorticoids, enhances tight junction formation and expression of the tight junction protein occludin in mammary cells. Mol Cell Endocrinol 1999 156 55-61. 

Bolton SJ, Anthony DC, Perry VH Loss of the tight junction proteins occludin and zonula occludens-1 from cerebral vascular endothelium during neutrophil-induced blood-brain barrier breakdown in vivo. Neuroscience 1998 86 1245-1257. 

Figure 2 Diabetes leads to loss of the tight junctions while glucocorticoids induce assembly of tight junctions. In diabetes, VEGF produced from the neural retina as well as inflammatory cytokines cause phosphorylation of occludin, tight junction disassembly, and loss of tight junction proteins. Steroids induce the synthesis of tight junction proteins, assembly of tight junctions at the cell border, and dephosphorylation of occludin associated with increased barrier properties in vitro and may induce barrier formation in vivo. Abbreviation VEGF, vascular endothelial growth factor.

Fanning AS, Jameson BJ, Jesaitis LA, Anderson JM. The tight junction protein ZO-1 establishes a link between the transmembrane protein occludin and the actin cytoskele-ton. J Biol Chem 1998 273 29,745-29,753. 

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