Tight Junction Protein Pathway (TJ Pathway)

The tight junction protein pathway refers to the network of proteins and signaling mechanisms that form and regulate tight junctions (TJs) in epithelial, endothelial, and some myelinated cells. Tight junctions are specialized intercellular connections that create a selective barrier at the apical region of cell-cell contacts, controlling paracellular transport (movement between cells) and maintaining cell polarity. The main structural components include Claudins, Occludin, Junctional Adhesion Molecules (JAMs), and Marvel domain-containing proteins. Intracellularly, these transmembrane proteins connect to scaffolding/adaptor proteins like ZO-1. TJs seal the paracellular space between cells, preventing uncontrolled passage of ions, water, solutes, pathogens, or immune cells. They also help maintain cellular polarity. TJ proteins participate in intracellular signaling pathways regulating cell proliferation, migration/differentiation. Dysregulation is implicated in diseases including cancer progression/metastasis due to altered signaling pathways affecting growth/migration.

Other names

Tight Junction SignalingTJ proteinsIntercellular junction pathway