title: Making water-soluble integral membrane proteins in vivo using an amphipathic protein fusion strategy.
abstract: Integral membrane proteins (IMPs) play crucial roles in all cells and represent attractive pharmacological targets. However, functional and structural studies of IMPs are hindered by their hydrophobic nature and the fact that they are generally unstable following extraction from their native membrane environment using detergents. Here we devise a general strategy for in vivo solubilization of IMPs in structurally relevant conformations without the need for detergents or mutations to the IMP itself, as an alternative to extraction and in vitro solubilization. This technique, called SIMPLEx (solubilization of IMPs with high levels of expression), allows the direct expression of soluble products in living cells by simply fusing an IMP target with truncated apolipoprotein A-I, which serves as an amphipathic proteic 'shield' that sequesters the IMP from water and promotes its solubilization.
authors: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
authors: Dario
authors: D
authors: Mizrachi
authors: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors: Yujie
authors: Y
authors: Chen
authors: Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Jiayan
authors: J
authors: Liu
authors: Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Hwei-Ming
authors: HM
authors: Peng
authors: Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA.
authors: Ailong
authors: A
authors: Ke
authors: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors: Lois
authors: L
authors: Pollack
authors: Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada T2N 1N4.
authors: Raymond J
authors: RJ
authors: Turner
authors: Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Richard J
authors: RJ
authors: Auchus
authors: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
authors: Matthew P
authors: MP
authors: DeLisa
mesh_terms: D000954:Antigens, Surface / Q000737:chemistry / Q000378:metabolism*; D017920:Antiporters / Q000737:chemistry / Q000378:metabolism*; D016632:Apolipoprotein A-I / Q000737:chemistry / Q000378:metabolism*; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D001428:Bacterial Vaccines / Q000737:chemistry / Q000378:metabolism*; D025065:Borrelia burgdorferi; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism*; D057927:Hydrophobic and Hydrophilic Interactions; D008074:Lipoproteins / Q000737:chemistry / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D012995:Solubility
chemical_list: D000954:Antigens, Surface; D017920:Antiporters; D016632:Apolipoprotein A-I; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D029968:Escherichia coli Proteins; D008074:Lipoproteins; D008565:Membrane Proteins; C072045:OspA protein; C075436:EmrE protein, E coli