S1P receptor signal transduction

Metabolism of sphingomyelin by the sphingomyelinase, ceramidase (Cer'ase) and the sphingosine kinase (SK) enzymes results in formation of S1P and receptor activation. Autocrine and paracrine modes of receptor activation have been implied but have yet to be rigorously proven. Critical signaling molecules, such as phospholipase C (PLC), ERK, PI3K, and Akt are activated. Active Akt binds to the receptor and phosphorylates the third intracellular loop, which is essential for Rac activation.

鞘磷脂酶、鞘氨醇酶（Cer'ase）和鞘氨醇激酶（SK）酶对鞘磷脂的代谢作用导致S1P的形成及受体的激活。受体激活的旁分泌和自分泌模式已被暗示，但尚未得到严格的证实。关键的信号分子，如磷脂酶C（PLC）、ERK、PI3K和Akt被激活。活化的Akt与受体结合，并磷酸化第三个细胞内环，这对于Rac的激活至关重要。