Description
Catalyzes the hydrolysis of the 4-position phosphate of phosphatidylinositol 3,4-bisphosphate, inositol 1,3,4-trisphosphate and inositol 1,4-bisphosphate. Involved in the regulation of megakaryocyte and fibroblast proliferation. Regulates cell growth downstream of transcription factor GATA-1