Opalin (oligodendrocytic myelin paranodal and inner loop protein) is a brain specific, single-pass type I membrane protein []. Its function is not clear. In mouse, it is expressed specifically in oligodendrocytes of the brain [, , ]. It is induced by leukemia inhibitory factor (LIF) and cAMP analogs. It is suppressed in the presence of astrocytic or neural-stem-like differentiation factors such as bone morphotic protein (BMP) and fetal calf serum [].
