Research Interests of the lipid signalling group
Lipid-mediated signalling and exocytosis
Phosphoinositides have been in the limelight for over two decades following their identification as sources of the second messengers, diacylglycerol (DG), inositol(1,4,5) trisphosphate (IP3) and phosphatidylinositol(3,4,5)trisphosphate (PI(3,4,5)P3). The last 10 years have witnessed an explosion of experimental results that demonstrate inositol lipids themselves, in particularly PI(4,5)P2, should be considered as second messengers in their own right. The inositol headgroup of phosphatidylinositol (PtdIns) can be phosphorylated at single or multiple sites to give rise to seven different phosphoinositides.
Phosphoinositides can control many biological processes via their ability to interact with specific protein domains. Many domains including the PH, PX, ENTH domains can bind to specific species of phosphoinositides. This recruitment can be transient depending on the life-time of the phosphoinositides, which is governed by the kinases and the phosphatases which will regulate their levels in specific locations. Proteins recruited in this manner can thus regulate membrane trafficking events including endocytosis, exocytosis, vesicle budding at the Golgi, actin assembly and other biological processes.
The work of the Lipid Signalling Group focuses on mechanisms that regulate phosphoinositide synthesis and the downstream functions of phosphoinositides in membrane traffic and in lipid mediated downstream signalling.