Editing Kinase (section)

===Sphingosine kinases===
Sphingosine kinase (SK) is a lipid kinase that catalyzes the conversion of [[sphingosine]] to [[sphingosine-1-phosphate]] (S1P). Sphingolipids are ubiquitous membrane lipids. Upon activation, sphingosine kinase migrates from the cytosol to the plasma membrane where it transfers a γ phosphate (which is the last or terminal phosphate) from [[Adenosine triphosphate|ATP]] or [[Guanosine triphosphate|GTP]] to sphingosine. The S1P receptor is a [[GPCR]] receptor, so S1P has the ability to regulate G protein signaling. The resulting signal can activate intracellular effectors like ERKs, [[Rho family of GTPases|Rho GTPase]], [[Rac (GTPase)|Rac GTPase]], [[phospholipase C|PLC]], and AKT/PI3K. It can also exert its effect on target molecules inside the cell. S1P has been shown to directly inhibit the histone deacetylase activity of [[HDAC]]s. In contrast, the dephosphorylated sphingosine promotes cell [[apoptosis]], and it is therefore critical to understand the regulation of SKs because of its role in determining cell fate. Past research shows that SKs may sustain cancer cell growth because they promote cellular-proliferation, and SK1 (a specific type of SK) is present at higher concentrations in certain types of cancers.

There are two kinases present in mammalian cells, SK1 and SK2. SK1 is more specific compared to SK2, and their expression patterns differ as well. SK1 is expressed in lung, spleen, and leukocyte cells, whereas SK2 is expressed in kidney and liver cells. The involvement of these two kinases in cell survival, proliferation, differentiation, and [[inflammation]] makes them viable candidates for [[chemotherapy|chemotherapeutic therapies]].<ref>{{cite journal | vauthors = Neubauer HA, Pitson SM | title = Roles, regulation and inhibitors of sphingosine kinase 2 | journal = The FEBS Journal | volume = 280 | issue = 21 | pages = 5317–5336 | date = November 2013 | pmid = 23638983 | doi = 10.1111/febs.12314 | doi-access = free }}</ref>