Alpha Lifetech Inc. focuses on recombinant proteins' expression in different biosystems for many years, including prokaryotic and eukaryotic organism, and also for the development of novel high-potency recombinant proteins to meet your technical, program, and budget requirements.
Membrane Proteins & Cell lines - G Protein-Coupled Receptor Expression Service
G-protein-coupled receptors (GPCRs), also called G protein–linked receptors (GPLR) or 7TM receptors, are the largest and most diverse group of membrane receptors in eukaryotes including yeast, choanoflagellates and animals. So far as, one-third known genes in human cells code membrane proteins in which two-third of these membrane proteins are GPCRs or GPCRs related proteins. In fact, researchers estimate that between one-third and one-half of all marketed small molecules act by binding to GPCRs.
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Figure 1. 2-D structure of GPCR: Seven-transmembrane domain; C (1-4) and E (1-4) loops interact with signaling molecules inside or outside cell matrix |
Figure 1 shows that a single polypeptide folds into GPCR and seven segments of this molecule span the entire width of the membrane embed in a cell's plasma membrane. While the 3-D structure of GPCRs look like a globular shape and the extracellular loops form part of the pockets at which signaling molecules bind to the GPCR.
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Figure 2. 3-D structure of GPCRs: Endogenous agonist bounds to the seven-transmembrane domain which changes the conformation of GPCR and then actives cellular signaling pathway |
GPCRs need to combine other subunits (α, β, γ subunit) in order to play a whole function. G protein (α subunit) possesses GTPase activity which can hydrolyse GTP and then provide energy for this molecular machine to transform the conformation of GPCRs, show in figure 3:
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Figure 3. Actives cellular signaling pathway induced by GPCRs |
To produce functional and native GPCRs membrane proteins, Alpha Lifetech Inc. has developed a powerful Cell/Cell-free Expression platform based on different organisms including bacteria, plant and mammal cells. Alpha Lifetech Inc. can express recombinant proteins, especially membrane proteins, in a form of precipitation without detergents or a solubilized form in 24 detergents in cell-free systems, according to different applications and requirements of each project to meet the need of our clients.