Table 1.
List of GPCRs affected by membrane cholesterol.
| GPCR | Effect of membrane cholesterol | References |
|---|---|---|
| β2-adrenergic | Cholesterol improves stability of the receptor and facilitates its crystallization. It also modulates isolation of the receptor from its signaling components in liquid-ordered lipid nanodomains, and thereby affects signaling. | Ben-Arie et al., 1988; Hanson et al., 2008; Pontier et al., 2008 |
| Cannabinoid | CB1R is dependent on cholesterol concentrated in lipid rafts for ligand binding and signaling and the CRAC motif is responsible for its direct interaction with membrane cholesterol. | Bari et al., 2005a,b; Oddi et al., 2011 |
| Chemokine | Cholesterol is essential for CXCR4 and 5 conformation and function. | Nguyen and Taub, 2002a,b, 2003 |
| Cholecystokinin | Cholesterol interacts at specific sites in the transmembrane segments of the CCK1R (CCKAR), and affects its ligand binding and signaling abilities. CCK2R (CCKBR) is not affected. | Gimpl et al., 1997, 2002; Harikumar et al., 2005b; Potter et al., 2012 |
| Dopamine | D1 receptors in renal cells can associate with caveolin-2 in caveolae, where they activate adenylate cyclase. | Yu et al., 2004; Genedani et al., 2010 |
| Galanin | Membrane cholesterol supports the ligand binding process in a positively co-operative manner. | Pang et al., 1999 |
| Metabotropic glutamate | Enrichment of cholesterol in Drosophila melanogaster photoreceptor cell membranes induces receptor association with lipid rafts and shift to the high affinity state. | Eroglu et al., 2003 |
| Muscarinic | Cholesterol promotes cooperativity in binding of antagonists to the M2 muscarinic receptors. | Colozo et al., 2007 |
| Neurokinin | Monomeric neurokinin-1 receptors are localized in the lipid rafts and caveolae. Cholesterol content is directly proportional to the signaling. | Monastyrskaya et al., 2005; Meyer et al., 2006 |
| Opioid | Cholesterol present in lipid rafts and caveolae is important for agonist affinity, where it affects G protein coupling. | Lagane et al., 2000; Xu et al., 2006; Huang et al., 2007 |
| Oxytocin | Amount of cholesterol in the membrane is directly proportional to the ligand binding affinity of the receptor. | Gimpl et al., 1997, 2002; Gimpl and Fahrenholz, 2002 |
| Serotonin | Reduction in cholesterol compromises organization, ligand binding, and G protein coupling at the 5HT1A and 5HT7A receptors. | Pucadyil and Chattopadhyay, 2004, 2005; Sjogren et al., 2006 |
| Rhodopsin | Elevated cholesterol inhibits the activation of rhodopsin receptor. | Mitchell et al., 1990; Niu et al., 2002; Bennett and Mitchell, 2008 |