Epithelial cell tight junction proteins (TJ protein)

Tight junction proteins are a family of mostly transmembrane and associated cytosolic proteins that assemble into complexes at the apico-lateral border of epithelial cells, forming the tight junction. These proteins—including the claudins (over 27 members), occludin, JAMs, tricellulin, and zonula occludens—maintain a size- and charge-selective barrier for paracellular flux, regulate epithelial permeability and cell polarity, and serve as signaling hubs for cell differentiation and immune function[1][2][4][5][7]. Dysfunction or altered expression of tight junction proteins is implicated in many diseases, making them a significant focus for research and therapeutic modulation[2][4][5]. Note: The term "Epithelial cell tight junction proteins" is too broad and informal to be a canonical target name; for structured data, specify the individual protein (e.g., "Claudin-1," "Occludin," or "Junctional adhesion molecule-A")[1][4][5][7].

Other names

Tight junction proteinsTJ proteinsParacellular barrier proteinsZonula occludens proteins (for associated cytosolic scaffolds)

Modulation of junctional structure and paracellular permeability via phosphorylation, cytoskeletal rearrangement, or altered expression/localization Targeting occludin, claudin, or JAM proteins to regulate barrier tightness Disruption by pathogens (e.g., by binding JAM-A)