Deciphering the lipid code for SLC7 transporters using native MS and cryoEM
LEAD SUPERVISOR: Professor Simon Newstead, Department of Biochemistry
Co-supervisor: Professor Stephen Tucker, Department of Physics
Co-supervisor: Dr Jo Parker, Department of Biochemistry
Commercial partner: OMass Therapeutics, Oxford
Solute carrier transporters (SLC) are integral membrane proteins that mediate the uptake, extrusion and exchange of small molecules across biological membranes. SLCs represent the second largest family of membrane proteins in the human genome and are linked to numerous metabolic, neurological and developmental diseases. In recent years mounting evidence has indicated an important but unclear role for lipids in mediating the function of SLC proteins and linking disease phenotypes to dysregulation of lipid interactions in the cell. Recent work our group, funded through an MRC grant, has discovered that phospholipids can regulate oligomeric state, control on/off states and regulate trafficking in the cell. However, a mechanistic understanding and roadmap of lipid regulated functions within the SLC family remain elusive. Our project, in partnership with OMass therapeutics, will directly address this question through a unique combination of in vitro and in vivo biochemistry, structural studies using cryo-EM and native mass spectrometry (MS) coupled with lipidomics. Specifically, the student will use a range of synthetic nanobodies targeted to SLC proteins that reside in specific locations in the cell and use these binders to affinity purify the target proteins for subsequent lipid analysis using native MS. These studies will be complemented with in vivo nanodisc reconstitutions, which will enable native-like purification of the proteins for single particle cryo-EM. Insights gained from the native MS data will be used to assign lipid densities in the cryo-EM maps, whilst also serving to inform and direct in vitro transport assays in liposomes of defined lipid composition. The resulting data will be used to develop a blueprint for understanding the importance of specific lipid types (phospholipid vs. cholesterol) in SLC biology and advance our understanding of this neglected aspect of molecular membrane biology.
Apply using course: DPhil in Biochemistry