SPHK2 phosphorylates sphingoid

The cytosolic enzyme sphingosine kinase 2 (SPHK2) catalyzes the phosphorylation of sphingoids (SPG) to sphingoid 1-phosphate (S1P). The main product is sphingosine 1-phosphate, a bioactive lipid that acts extracellularly on G protein-coupled receptors of the S1P1/EDG-1 subfamily (Liu et al., 2000; reviewed by Siow & Wattenberg, 2011). Through alternative splicing, the isoforms of SK2a and SK2b are produced that show functional differences in their activity (reviewed by Hatoum et al., 2017). In contrast to pro-survival SPHK1, the BH3-only protein SPHK2 inhibits cell growth and enhances apoptosis (Maceyka et al., 2005).

细胞质酶鞘氨醇激酶2（SPHK2）催化鞘氨醇（SPG）磷酸化为鞘氨醇1-磷酸（S1P）。其主要产物为鞘氨醇1-磷酸，一种具有生物活性的脂质，在细胞外通过作用于S1P1/EDG-1亚族的G蛋白偶联受体发挥功能（刘等，2000；参见Siow和Wattenberg，2011年综述）。通过选择性剪接，产生SK2a和SK2b等异构体，它们在活性上表现出功能差异（参见Hatoum等，2017年综述）。与促生存的SPHK1相反，仅含BH3结构域的蛋白SPHK2抑制细胞生长并促进细胞凋亡（Maceyka等，2005年）。