TJP1
TJP1 (tight junction protein 1, also known as ZO-1) is a MAGUK-family scaffolding protein that links tight junction transmembrane proteins to the actin cytoskeleton. It helps form the tight junction belt that regulates paracellular movement between epithelial and endothelial cells. Browse Assay Genie's current range of TJP1 research reagents below, or read on for the biology behind the target.
TJP1 is a scaffolding protein that connects tight junction (TJ) transmembrane proteins, such as claudins, junctional adhesion molecules and occludin, to the actin cytoskeleton. It forms a multistranded TJP1/ZO1 condensate that elongates into a tight junction belt, which is anchored at the apical cell membrane through interaction with PATJ. The tight junction limits movement of substances through the paracellular space and acts as a boundary between the compositionally distinct apical and basolateral plasma membrane domains of epithelial and endothelial cells. TJP1 is necessary for lumenogenesis and for efficient epithelial polarisation and barrier formation.
Beyond barrier function, TJP1 plays a role in regulating cell migration by targeting CDC42BPB to the leading edge of migrating cells. It is also important for podosome formation and associated function, thereby influencing cell adhesion and matrix remodelling. Together with TJP2 and TJP3, it participates in the junctional retention and stability of the transcription factor DBPA, although it is not involved in shuttling DBPA to the nucleus. It may also contribute to cell morphology changes during ameloblast differentiation through its role in tight junctions.
The TJP1 gene encodes a member of the membrane-associated guanylate kinase (MAGUK) family, and acts as a tight junction adaptor protein that also regulates adherens junctions. Its multidomain structure, comprising a PDZ domain, an SH3 domain, a guanylate kinase (GuK) domain and unique (U) motifs, coordinates binding of transmembrane proteins, cytosolic proteins and F-actin, all of which are required for tight junction function. UniProt records localisation at the cell membrane, tight junctions, gap junctions and podosomes. Alternative splicing produces multiple transcript variants encoding different isoforms. The protein is also known as ZO-1, and mouse and rat orthologues are designated Tjp1.
TJP1 is necessary for efficient epithelial polarisation and barrier formation, making it a central protein for studying tight junction assembly.
Tight junctions regulate the movement of ions and macromolecules between cells, and TJP1 scaffolds the complexes that control this paracellular passage.
TJP1 targets CDC42BPB to the leading edge of migrating cells and supports podosome formation, linking it to adhesion and matrix remodelling.
TJP1 is required for lumenogenesis and anchors the tight junction belt at the apical membrane via PATJ, informing studies of apical-basolateral polarity.
TJP1 is a scaffolding protein that links tight junction transmembrane proteins, including claudins, junctional adhesion molecules and occludin, to the actin cytoskeleton. It forms the tight junction belt, supports epithelial polarisation and barrier formation, and also contributes to cell migration and podosome formation.
Yes. ZO-1 (zona occludens 1) is an alias of TJP1; MGC133289 and DKFZp686M05161 are other listed names. The gene undergoes alternative splicing, giving multiple transcript variants that encode different isoforms. TJP1 is a member of the MAGUK family alongside related proteins TJP2 and TJP3.
Orthologues exist in mouse and rat, both designated Tjp1. TJP1 belongs to the MAGUK family and has close relatives TJP2 and TJP3 that share scaffolding roles at tight junctions. Check the datasheet of any product for its validated reactivity.
Other tight junction scaffold proteins, junctional partners and cell polarity targets with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q07157; product specifications from Assay Genie datasheets.