Sphingosine kinase (SphK)

Sphingosine kinase (SphK) is an enzyme that catalyzes the phosphorylation of sphingosine to sphingosine-1-phosphate (S1P), a potent signaling lipid that mediates diverse cellular functions including cell survival, proliferation, migration, apoptosis, and immune responses[1][2][3][4][6]. There are two main isoforms in mammals, SphK1 and SphK2, encoded by distinct genes and differing in tissue distribution, subcellular localization, and functional roles[4][6]. SphK1 is primarily cytoplasmic and translocates to the plasma membrane upon activation, while SphK2 is found in the nucleus, mitochondria, and endoplasmic reticulum[4]. S1P produced by SphKs acts intracellularly to regulate processes such as gene expression and epigenetic modification (e.g., via inhibition of histone deacetylases), and extracellularly as an agonist for S1P receptors (S1PR1–5), affecting angiogenesis, immunity, and inflammation[4][5][6]. SphK and the S1P pathway are implicated in a variety of diseases and have become therapeutic targets for cancer, autoimmune, and neurodegenerative disorders. Notably, the immunomodulatory drug fingolimod (FTY720) is phosphorylated by SphK2 to modulate S1P receptor signaling, underlying its approved use in multiple sclerosis[6].

Other names

SphKsphingosine kinase 1 (SphK1)sphingosine kinase 2 (SphK2)SPHK1SPHK2

Inhibition of sphingosine-1-phosphate (S1P) synthesis, modulation of S1P receptor signaling, regulation of histone deacetylation (via S1P), antagonism of pro-survival signaling pathways