G-protein-coupled seven-transmembrane receptors

Feng Y, Broder CC, Kennedy PE, Berger EA (1996) HIV-1 entry cofactor functional cDNA cloning of a seven-transmembrane, G protein-coupled receptor. Science 272 872-877 Fernandez EJ, LoUs E (2002) Structure, function, and inhibition of chemokines. Annu Rev Pharmacol Toxicol 42 469-499... 

It is universally accepted that the action of opioids is mediated by specific receptors. It is presumed that several types of opioid receptors exist p, k, 5, and a. A few of these are in turn subdivided into subtypes. It has been found that opioid receptors are seven transmembrane G-protein-coupled receptors that are localized in the membranous part of the synaptosomal head it has also been found that they are glycoproteins. They are prone to conformational changes in certain situations, which is essential for their selective binding with agonists or antagonists. 

Adrenergic transmission is well known to be involved in the regulation of homeostatic control through its functions in the autonomic nervous system. Additionally, adrenergic projections in the brain have been identified with important roles in neurocognition. Adrenoreceptors are seven transmembrane G-protein-coupled receptors that mediate the physiological responses of epinephrine and norepinephrine. The first classification of these receptors resolved a (alpha)-adrenoreceptors (aARs) from P (beta)-adrenoreceptors (PARs) (Ahlquist, 1948). Since then, additional subtypes and variants have been described. 

RN Zuckermann, EJ Martin, DC Spellmeyer, GB Stauber, KR Shoemaker, JM Kerr, GM Figliozzi, DA Goff, MA Siani, RJ Simon. Discovery of nanomolar ligands for seven transmembrane G-protein coupled receptors from a diverse peptoid library. J Med Chem 37 2678-2685, 1994. 

Su SB, Gong W, Gao JL, Shen W, Murphy PM, Oppenheim JJ, Wang JM (1999) A seven-transmembrane, G protein-coupled receptor, FPRLl, mediates the chemotactic activity of serum amyloid A for human phagocytic cells. J Exp Med 189 395-402... 

Feng, Y., Broder, C. C., Kennedy, P. E., and Berger, E. (1996). HIV-1 entry co-factor functional cDNA cloning of a seven-transmembrane G-protein coupled receptor. Science 272, 872-877. 

Figure 2.5. A schematic of a p-lactamase reporter cell line that is coupled through a seven transmembrane G-protein—coupled receptor whose second messenger signaling pathway operates through cyclic adenosine monophosphate (cAMP). The G-protein, Gas, activates adenyl cyclase, increasing the concentration of cAMP, which stimulates the production of p-lactamase through cAMP response element.

The chemokine receptors are a diverse family of seven-transmembrane G-protein-coupled receptors binding a large family of ligands. Chemokine receptors were first identified on leukocytes and mediate directed migration of many host cells to sites of ligand expression. It is now well established that most malignant cells also express one or more chemokine receptor. This volume will summarize the growing body of evidence that several chemokine receptors contribute to tumor behavior. 

Another cDNA that encodes a cannabinoid receptor was cloned by Munro et al. (1993). This cannabinoid receptor (the CBj receptor) is also a seven-transmembrane, G protein-coupled receptor and consists of 360 amino acids. The CBj receptor is mainly expressed in the immune system such as the spleen and tonsil and lymph nodes. The CBj receptor is abnndantly expressed in several types of leukocytes, such as B cells, macrophages/monocytes, and natnral killer cells, and is assumed to participate in the regulation (stimnlation or inhibition) of inflammatory reactions and immune responses. (For reviews, see Berdyshev, 2000 Di Marzo, Melck, et al., 2000 De Petrocellis et al., 2000 Parolaro et al., 2002 Cabral, 2002 and Roth et al., 2002.)... 

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