 Studies have shown that rather than being important in tight junction assembly, occludin is important in tight junction stability and barrier function.Furthermore, studies in which mice were deprived of occludin expression showed morphological stability in several epithelial tissues but also found chronic inflammation and hyperplasia in the gastric epithelium, calcification in the brain, testicular atrophy, loss of cytoplasmic granules in straited duct cells of salivary gland, and thinning of the compact bone.The phenotypical response of these mice to the lack of occludin suggest that the function of occludin is more complex than thought and requires more work.