该基因编码的蛋白质催化磷脂酰肌醇4，5-二磷酸形成肌醇1，4，5-三磷酸和二酰甘油该反应以钙为辅因子，在受体介导的酪氨酸激酶激活剂的细胞内转导中起重要作用。例如，当被SRC激活时，编码的蛋白质导致Ras鸟嘌呤核苷酸交换因子RasGRP1转移到高尔基体，在高尔基体激活Ras此外，该蛋白已被证明是肝素结合生长因子1（酸性成纤维细胞生长因子）激活酪氨酸激酶的主要底物已经发现了两个编码不同亚型的转录变体。[由RefSeq提供，2008年7月]
The protein encoded by this gene catalyzes the formation of inositol 1,4,5-trisphosphate and diacylglycerol from phosphatidylinositol 4,5-bisphosphate. This reaction uses calcium as a cofactor and plays an important role in the intracellular transduction of receptor-mediated tyrosine kinase activators. For example, when activated by SRC, the encoded protein causes the Ras guanine nucleotide exchange factor RasGRP1 to translocate to the Golgi, where it activates Ras. Also, this protein has been shown to be a major substrate for heparin-binding growth factor 1 (acidic fibroblast growth factor)-activated tyrosine kinase. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]