Phosphorylates PtdIns, PtdIns4P and PtdIns(4,5)P2. May play a role in clathrin-coated endocytic vesicle formation and EGF signaling cascade. May be involved in mitosis and UV-induced damage response. May be a downstream effector in insulin signaling cascade.
Expressed in columnar and transitional epithelia, mononuclear cells, smooth muscle cells, and endothelial cells lining capillaries and small venules (at protein level). Ubiquitously expressed, with highest levels in heart, placenta and ovary, and lowest levels in the kidney.
Belongs to the PI3/PI4-kinase family. Contains 1 C2 domain. Contains 1 PI3K/PI4K domain. Contains 1 PX (phox homology) domain.
Phosphorylated upon insulin stimulation; which may lead to enzyme activation (By similarity). Phosphorylated on Ser-259 during mitosis and upon UV irradiation; which does not change enzymatic activity but leads to proteasomal degradation. Ser-259 phosphorylation may be mediated by CDK1 or JNK, depending on the physiological state of the cell.
Cell membrane. Golgi apparatus. Cytoplasmic vesicle > clathrin-coated vesicle. Nucleus. Cytoplasm. According to PubMed:10766823 and PubMed:11239472, it is found in the cell membrane, the Golgi apparatus and in clathrin-coated vesicles. According to PubMed:17038310 it inserts preferentially into membranes containing PtdIns(4,5)P2. According to PubMed:11606566, it is nuclear and cytoplasmic. Associated with RNA-containing structures. According to PubMed:14563213, it is mainly cytoplasmic.