title: Claudin switching: Physiological plasticity of the Tight Junction.
abstract: Tight Junctions (TJs) are multi-molecular complexes in epithelial tissues that regulate paracellular permeability. Within the TJ complex, claudins proteins span the paracellular space to form a seal between adjacent cells. This seal allows regulated passage of ions, fluids, and solutes, contingent upon the complement of claudins expressed. With as many as 27 claudins in the human genome, the TJ seal is complex indeed. This review focuses on changes in claudin expression within the epithelial cells of the gastrointestinal tract, where claudin differentiation results in several physiologically distinct TJs within the lifetime of the cell. We also review mechanistic studies revealing that TJs are highly dynamic, with the potential to undergo molecular remodeling while structurally intact. Therefore, physiologic Tight Junction plasticity involves both the adaptability of claudin expression and gene specific retention in the TJ; a process we term claudin switching.
authors.affiliation: Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, United States.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Capaldo
authors.affiliation: Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, United States; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, United States. Electronic address: anusrat@umich.edu.
authors.forename: Asma
authors.initials: A
authors.lastname: Nusrat
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D057167:Claudins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D004847:Epithelial Cells / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000166:cytology* / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D010539:Permeability; D019108:Tight Junctions / Q000502:physiology*
chemical_list: D057167:Claudins
keywords: Claudin; Homeostasis; Inflammation; Tight Junction