Paul Gleeson Professor - Department of Biochemistry and Molecular ...

HeLa cell expressing a epitope taggedmembraneprotein, mutated in a Tyrbasedinternalization motif, resultingin the accumulation of the membraneprotein (red) on the cell surface oftransfected cells. 3D reconstruction ofconfocal images showing membraneprotein (red), Golgi marker (green) andnuclear DAPI staining (blue).4. Signals for endosomal sorting in development and diseaseA number of important membrane proteins recycle between the plasmamembrane and the Golgi, and this recycling is essential for their function.Perturbation of these pathways can result in diseases, including neurodegenerativediseases such as Alzheimer’s disease. Very little is known about the targetingsignals of cargo proteins that define this transport pathway. This project willdefine these targeting signals by the generation and analysis of mutants ofmembrane cargos using defined transport assays and by the silencing pathwayspecifictrafficking machinery.References/publications/recommended reading1. Kerr M.C., Lindsay M.R. Luetterforst R., Hamilton N., Simpson F., Parton R.G., Gleeson P.A., TeasdaleR.D. (2006). Visualisation of macropinosome maturation by the recruitment of sorting nexins. J. Cell Sci.119:3967‐80.2. Lieu, Z.Z., Lock, J.G., Hammond, L.A., La Gruta, N. L, Stow, J. L. and Gleeson, P.A. (2008). A trans‐Golginetwork golgin is required for the regulated secretion of TNFa in activated macrophages in vivo. Proc. Natl.Acad. Sci USA, 105:3351‐63. Houghton F, Chew PL, Lohedo S, Goud B and Gleeson PA (2009) The localization of the golgin, GCC185,is independent of Rab6 and Arl1. Cell 138: 787‐7944. Gleeson PA and Goud, B (2010) TGN golgins, Rabs and cytoskeleton: Regulating the Golgi trafficking highways. Trends Cell Biol 20(6):329‐36.5. Phey Lim, J. and Gleeson, P.A. (2011). Macropinocytosis: An endocytic pathway for internalising large gulps. Immunol Cell Biol 89:836‐8436. Chia, PZC, Gasnereau, I, Lieu, ZZ and Gleeson, PA (2011). Rab‐9 dependent retrograde transport and endosomal sorting of the endopeptidase,furin. J. Cell Sci. 124:2401‐2413Autoimmunity and molecular immunology –Collaborators Professor Ian van Driel and Dr Dorothee Bourges,Department of Biochemistry and Molecular BiologyFailure of immunological self‐tolerance often leads to the development of autoimmune diseases, whichafflict up to 5% of the population. The underlying causes of autoimmune diseases are still unknown,although infections are strong candidates for initiating autoimmunity by promoting the maturation ofdendritic cells (DCs) that present tissue self‐antigens. Research in the van Driel/Gleeson laboratory focuseson defining how autoimmune disease develops, with a particular emphasis on the role of dendritic cells andregulatory T cells. The lab works on a murine model of autoimmune gastritis, a highly define system inwhich the target autoantigen is naturally expressed in the stomach.This project will analyse the relationship between inflammatory stimuli, the maturation status of DCs thatpresent gastric self‐epitopes and the development of organ‐specific autoimmunity.We have established an experimental autoimmune disease of the stomach(autoimmune gastritis) as a powerful model of organ‐specific autoimmunityand have identified the gastric autoantigens that are recognized by the selfreactiveeffector T cells. CD4 + T cells that mediate the disease recognize thehighly abundant gastric H/K ATPase heterodimer. Immune tolerance to thesegastric self‐antigens occurs primarily in the periphery. Most importantly, wehave also identified a subpopulation of migratory DCs in the draining lymphnode of the stomach that presents the endogenous gastric H/K ATPaseantigen. Hence, we are now able to compare the status of DCs whichpresent the gastric antigen, from normal mice and mice with autoimmunegastritis, as a basis for understanding the shift from tolerance toautoimmunity. This project will involve the isolation of the migratorypopulation of DCs by standards methods in the lab, analysis of TLR expression of these migratory DCs andassessment of the impact of different TLR ligands on the maturation and functional status of these DCs byanalysis of cytokine profiles and activation of gastric‐specific effector T cell responses.Figure 2 Gastric cells express anautoantigen which is presented in thelocal draining lymph nodes by migratorydendritic cellReferences/publications/recommended reading.1. Read S, Hogan, T, Zwar, T, Gleeson, PA and van Driel, IR (2007). Prevention of autoimmune gastritis in mice requires extra‐thymic deletionand regulation of CD4+CD25+ T cells. Gastroenterology 133: 547‐552. Kim JM, Rasmussen, JP and Rudensky, AY. (2007) regulatory T cells prevent catastrophic autoimmunity throughout the lifespan of mice. NatImmunol 8, 191‐197.3. Allen, S, Turner, SJ, Bourges, D, Gleeson, PA and van Driel, IR (2011). Shaping the T‐cell repertoire in the periphery. Immunol Cell Biol. 89 : 60‐69 (IF 4.2)Page 15