Biological function of SPNS2: From zebrafish to human

Sphingosine-1-phosphate (S1P), a bioactive metabolite of sphingolipid, has an important role in lymphocyte trafficking, immune responses, vascular and embryonic development, cancer, bone homeostasis, etc. S1P is produced intracellularly and then secreted into the circulation to engage in the above physiological or pathological processes by regulating the proliferation, differentiation and survival of target cells; however, the underlying mechanisms of S1P secretion and function remain poorly understood. Recently, Spinster 2 (SPNS2), a newly identified transporter of S1P, was shown to act as a mediator of intracellular S1P release and play an important role in the regulation of S1P. In this review, we focus on the primary biological characteristics and functions of SPNS2 and provide novel insights into the development of therapies for S1P-related disorders.