ZO-2 (Tight Junction-associated Polypeptide, Zonula Occludens 2)

Human zona occludens 2 (ZO-2), an ~160kD tight junction protein belonging to the membrane-associated guanlyate kinase (MAGUK) family. Members of this family are involved in epithelial and endothelial intercellular junctions. They each contain at least one PSD95/Dlg/ZO-1 (PDZ) domain, a Src homology 3 (SH3) domain, and an enzymatically inactive guanylate kinase domain. PDZ domains are 90-amino acid protein-protein binding domains that recognize at least a 3-residue peptide motif in the COOH termini of their binding partners. PDZ domain-containing proteins, like ZO-2, typically act as scaffolding proteins that organize membrane receptors and cytosolic proteins into multimeric signaling complexes often at the sites of cell-cell contact. The effectiveness and stability of the epithelial barrier depends on a complex of proteins composing different intercellular junctions, which include tight junctions, adherens junctions, and desmosomes. ZO-2 can interact with zona occludens 1 (ZO-1). Furthermore, the PDZ2 domain of ZO-2 was shown to interact with connexin-43, the predominant connexin in epithelial and most other tissues which is involved in cell growth control and embryonic development. Applications: Suitable for use in Immunofluorescence, Western Blot, and Immunohistochemistry. Other applications not tested. Recommended Dilution: Immunofluorescence: 1:50 Western Blot: 1:50 Immunohistochemistry (frozen): 1:50 Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4 degrees C for short-term only. For long-term storage and to avoid repeated freezing and thawing, aliquot and store at -20 degrees C. Aliquots are stable for at least 12 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.