| Citation | Dr Irvine is distinguished for his contributions to the study of the biological functions of phospholipids, in particular the phosphoinositide signalling mechanism which is now recognised as being central to activation of many cellular processes. He made a major contribution to the experimental demonstrations that inositol (1,4,5) triphosphate is the second messenger responsible for calcium mobilization from the endoplasmic reticulum. More recently he has identified inositol (1,3,4) triphosphate and inositol (1,3,4,5) tetrakisphosphate as also being rapidly produced after stimulated phosphoinositide breakdown and demonstrated their metabolic interrelationship as part of a new pathway of inositol phosphate metabolism. He also showed that inositol (1,3,4,5) tetrakisphosphate has specific biological effects consistent with a messenger function. He has in addition contributed to our understanding of arachidonic acid metabolism in particular by his discovery of arachidonoyl specific CoA-mediated transacylation between phospholipids, and he has advanced our knowledge of inositide enzymology, especially by his demonstration of the profound effect of ionic environment and substrate structure on the activity and specificity of phosphoinositidase C. |