Biochemistry and genetics of inositol phosphate metabolism in Dictyostelium.
Biochemical and genetic data on the metabolism of inositol phosphates in the microorganism Dictyostelium are combined in a scheme composed of in five subroutes. The first subroute is the inositol cycle as found in other organisms: inositol is incorporated into phospholipids that are hydrolysed by PLC producing Ins(1,4,5)P3 which is dephosphorylated to inositol. The second subroute is the sequential phosphorylation of inositol to InsP6; the Ins(3,4,6)P3 intermediate does not release Ca2+. The third subroute is the sequential phosphorylation of Ins(1,4,5)P3 to InsP6 in a nucleus associated fraction, whereas the fourth subroute is the dephosphorylation of Ins(1,3,4,5,6)P5 to Ins(1,4,5)P3 at the plasma membrane. This last route mediates Ins(1,4,5)P3 formation in cells with a disruption of the single PLC gene. Finally, we recognize the formation of InsP7 and InsP8 as the fifth subroute.
van Haastert
P J
PJ
Department of Biochemistry, University of Groningen, The Netherlands.
van Dijken
P
P
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D004023:Dictyostelium / Q000235:genetics / Q000378:metabolism*; D007295:Inositol Phosphates / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000096:biosynthesis; D010766:Phosphorylation; D010738:Type C Phospholipases / Q000235:genetics / Q000378:metabolism
D007295:Inositol Phosphates; D010716:Phosphatidylinositols; D010738:Type C Phospholipases