Molecular composition of tight and adherens junctions in the rat olfactory epithelium and fila.

Tight and adherens junctions (TJs, AJs) between neurons, epithelial and glial cells provide barrier and adhesion properties in the olfactory epithelium (OE), and subserve functions such as compartmentalization and axon growth in the fila olfactoria (FO). Immunofluorescence and immunoelectronmicroscopy were combined in sections of rat OE and FO to document the cellular and subcellular localization of TJ proteins occludin(Occl), claudins(Cl) 1-5 and zonula occludens(ZO) proteins 1-3, and of AJ proteins N-cadherin(cad), E-cad, and alpha-, beta- and p120-catenin(cat). With the exception of Cl2, all TJ proteins were colocalized in OE junctions.