title: A complex affair: Attraction and repulsion make occludin and ZO-1 function!
abstract: Tight junctions (TJs) are protein complexes comprised of claudins, which anchor them in the membrane and numerous cytosolic scaffolding proteins including MAGI, MUPP1, cingulin and members of the Zonula Occludens (ZO) family. Originally, their main function was thought to be as a paracellular barrier. More recently, however, additional roles in signal transduction, differentiation and proliferation have been reported. Dysregulation is associated with a wide range of disease states, including diabetic retinopathy, irritable bowel disease and some cancers. ZO proteins and occludin form a protein complex that appears to act as a master regulator of TJ assembly/disassembly. Recent studies have highlighted the structural character of the primary ZO-1:occludin interaction and identified regions on occludin that control association and disassociation of TJ in a phosphorylation-dependent manner. We hypothesize that regions within ZO-1 in the so-called U5 and U6 regions behave in a similar manner.
authors.affiliation: Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey, PA USA.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Bewley
authors.affiliation: Renal Electrolyte and Hypertension Division; University of Pennsylvania; Philadelphia, PA USA.
authors.forename: Brian R
authors.initials: BR
authors.lastname: Tash
authors.affiliation: Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey, PA USA.
authors.forename: Fang
authors.initials: F
authors.lastname: Tian
authors.affiliation: Department of Biochemistry and Molecular Biology; Pennsylvania State University College of Medicine; Hershey, PA USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Flanagan
keywords: occludin; phosphorylation; structure; zonula occludens