The function of PI4K2A (phosphatidylinositol 4-kinase type 2 alpha, ENSG00000155252) is as follows. Membrane-bound phosphatidylinositol-4 kinase (PI4-kinase) that catalyzes the phosphorylation of phosphatidylinositol (PI) to phosphatidylinositol 4-phosphate (PI4P), a lipid that plays important roles in endocytosis, Golgi function, protein sorting and membrane trafficking and is required for prolonged survival of neurons. Besides, phosphorylation of phosphatidylinositol (PI) to phosphatidylinositol 4- phosphate (PI4P) is the first committed step in the generation of phosphatidylinositol 4,5-bisphosphate (PIP2), a precursor of the second messenger inositol 1,4,5-trisphosphate (InsP3). {ECO:0000269|PubMed:11279162, ECO:0000269|PubMed:16443754, ECO:0000269|PubMed:20388919, ECO:0000269|PubMed:23146885, ECO:0000269|PubMed:24675427, ECO:0000269|PubMed:25168678, ECO:0000305}.