PI4K2B
PI4KIIβ is the second type II phosphatidylinositol 4-kinase and the closest paralog of PI4K2A, sharing overall domain organization and N-ethylmaleimide sensitivity while differing in expression level and subcellular distribution. PI4K2B is expressed at lower abundance across tissues and has been localized to endosomal and Golgi compartments, where it contributes to generation of the PI4P used for membrane trafficking and for downstream PI(4,5)P2 synthesis. Because of its similarity to PI4KIIα, genetic redundancy between the two type II enzymes is thought to buffer PI4P production, and distinct physiological roles for PI4K2B are still being delineated.
