Mempro™ Pentameric Ligand-Gated Ion Channel Production Using Virus-Like Particles
Based on the comprehensive protein engineering platform established through years of experiences, experters form Creative Biostructure can provide specific custom Mempro™ pentameric ligand-gated ion channel (pLGIC) production services based on virus-like particles system.
pLGIC belongs to a single neurotransmitter receptor superfamily, which can regulate fast chemical transmission through converting nerve signals into an electrical response. The pLGICs are a group of transmembrane ion channels that open to allow ions such as Na+, K+, Ca2+, or Cl− to pass through the membrane, which are composed of five homologous subunits. It is shown that theses subunits consist of at least two different domains, including a transmembrane domain which forms the channel gate and the ion selective filter, and an extracellular domain which includes the ligand binding location (an allosteric binding site). In addition, pLGICs are divided into three classes: Cys-loop receptors, Ionotropic glutamate receptors and ATP-gated channels.
Figure 1. The schematic structure of the GABAA receptor. (Wikipedia)
Virus-like particles (VLPs) can simulate the native virus, but are non-infectious owing to they do not have any viral genetic materials. VLPs are self-assembly multiprotein structures, which are widely used in the field of vaccinology. VLPs derived from the Hepatitis B virus and composed of the small HBV derived surface antigen (HBsAg). Recently, virus-like particles carrying conformationally-complex membrane proteins (termed lipoparticles) have been applied for integral membrane protein production. Lipoparticles can incorporate a wide range of structurally intact membrane proteins, including G protein-coupled receptors (GPCRs), ion channels.
Creative Biostructure provides high-yield pLGICs in the stable, highly purified and native-conformation state. Lipoparticles can be produced from bacterial cells, yeast cells, insect cells, plant cells and mammalian cells for pLGICs production. Escherichia coli (E. coli) strains and insect cells are the most widely used systems for VLPs production. Mammalian cells are also widely used for VLPs production with the target to construct vaccine candidates and gene therapy agents. For instance, we can obtain lipoparticles from mammalian cells by co-expressing the retroviral structural core polyprotein, Gag, along with a desired membrane protein. Gag core proteins self-assemble at the plasma membrane, where they bud off and capture target membrane proteins. Since the pLGICs within lipoparticles are derived directly from the cell surface without mechanical disruption or detergents, the native structure and orientation of pLGICs are retained.
Creative Biostructure provides other various Mempro™ membrane protein production services. Please feel free to contact us for a detailed quote.
References:
A. Roldão, et al. (2010). Virus-like particles in vaccine development. Expert Rev. Vaccines, 9(10): 1149-1176.
J. A. Dent (2010). The evolution of pentameric ligand-gated ion channels. Adv. Exp. Med. Biol., 683: 11-23.
J. B. Corrie, et al. (2013). Gating of pentameric ligand-gated ion channels: structural insights and ambiguities. Structure, 21(8): 1271-1283.
S. Willis, et al. (2008). Virus-like particles as quantitative probes of membrane protein interactions. Biochemistry, 47(27): 6988-6890.
