Figure 1.
Schematic diagram of the BBB structure that comprises the tight and adherens junctions. The tight junctions consist of occludin, claudins, and junctional adhesion molecules (JAM). The tight junctions also consist of several accessory proteins necessary to form structural support, including the zonula occluden (ZO) proteins, AF6, 7H6, cingulin, and others. Most of the tight junction components (ZO proteins, claudin, and occludin) have the ability to bind to actin cytoskeleton in brain endothelial cells. The adherens junctions consist of vascular endothelial cadherin (VE-cadherin) and catenin proteins and provide structural integrity and attachment between the cells, and are necessary for formation of tight junctions. Updated from Abbott NJ, 2009 and other sources.