Invitrogen™ Occludin Monoclonal Antibody (OC-3F10), Alexa Fluor™ 488

Occludin is a 65 kDa protein that can exist in a variety of phosphorylated forms, ranging up to approximately 82 kDa. Occludin is thought to be involved in regulating both the localization and the function of occludin. Polyunsaturated fatty acids are known to up-regulate occludin expression, increasing the transendothelial cell resistance and reducing the cellular permeability to large molecules. The level of occludin varies greatly depending on tissue; in brain tissue, occludin is highly and continuously expressed at cell-cell contact sites, whereas non-neural tissues show lower expression and discontinuous distribution. Overall structural features of the occludin protein are highly conserved in all the species examined. Under-expression of tight junction proteins, including occludin, is a key molecular abnormality responsible for the increased permeability of tumor endothelial tight junctions, which contributes to brain tumor edemas.