Various stresses cause the accumulation of unfolded proteins in the endoplasmic reticulum（ER）. For this serious “ER stress”, cells have unfolded protein responses（UPR）consisted of the translation block, the induction of chaperones, and ER-associated degradation（ERAD）. If cells do not overcome the ER stress by UPR,ER-mediated apoptosis occurs. Recent reports showed that several diseases, such as diabetes, ischemic diseases, viral infections are caused by ER stress. In neuropsychiatric disorders, it was recently reported that ER stress involve in neurodegenerative diseases, such as Alzheimer disease and bipolar disorders.
 We are developing new drugs based on UPR theory to get the next generation drug for neuropsychiatric diseases. A molecular chaperone inducer（BIX）,which we recently invented, prevents neuronal death by ER stress, suggesting that it may be a potential therapeutic agent for neuropsychiatric diseases by ER stress.