Host: University of Birmingham, UK
Supervisory team: Mike Tomlinson and Steve Watson (University of Birmingham, UK); Angel Garcia (University of Santiago, Spain); Albert Sickmann and Robert Ahrends (Leibniz-Institut für Analytische Wissenschaften (ISAS), Germany)
Project locations: University of Birmingham, UK (Year 1 & 2), ISAS, Dortmund, Germany (Year 2), University of Santiago, Spain (Year 3)
Joint PhD Degree: University of Birmingham and University of Santiago de Compostela
Project details: Signalling by receptors, such as the platelet collagen/fibrin receptor GPVI, is critically dependent on the local lipid and protein membrane environment. GPVI has been reported to localise to both lipid raft and tetraspanin membrane microdomains. However, these studies have relied on membrane-disrupting detergents to isolate GPVI, such that the native membrane environment of GPVI remains undefined. We hypothesise that GPVI signalling is dependent on its interaction with specific lipids and membrane-associated proteins, and that these are altered upon GPVI activation or in the presence of GPVI-modulating therapeutics. To address this hypothesis, we will use an emerging technology for encapsulating, purifying and characterising membrane proteins in their local membrane environment. This approach, developed at the University of Birmingham, uses styrene maleic acid (SMA) copolymers as ‘molecular pastry cutters’ to convert the plasma membrane into nanodiscs, termed SMA lipid particles (SMALPs). We will affinity-purify GPVI-containing SMALPs from resting, activated and GPVI therapeutic-targetted platelets. These will be analysed for lipid and protein content using mass spectrometry-based lipidomic and proteomic methods. This work will provide fundamental new information on the mechanism of GPVI activation and signalling.
Reference: Lee et al (2016). A method for detergent-free isolation of membrane proteins in their local lipid environment. Nature Protocols 2016 11: 1149-62.
Desirable student skills: Biochemistry, Pharmacology, Structural biology.