Calbindin D28K and S100B have a similar interaction site with the lithium-inhibitable enzyme impase-1: a new drug target site

Lithium salts (Li) are used to treat bipolar disorder patients. Li inhibits inositol-monophosphatase (IMPase)-1. Calbindin D28k (calbindin) and S100B enhance IMPase-1 activity. We compared our in silico model of the IMPase-1/calbindin complex with the crystal structure of S100B. Although calbindin and S100B have a low sequence homology, they seem to activate IMPase-1 in a similar mode. It is reasonable that molecules interfering with the interaction of IMPase-1 with either of its activators will have Li-like effects.