7TM, Seven transmembrane

TM, seven transmembrane domain DOR, Drosophila odorant receptor EAG, electroantennogram GFP, green fluorescent protein GPCR, G-protein coupled receptor GR, gustatory receptor nsyb, neuronal synaptobrevin OR, odorant receptor OSN, olfactory sensory neuron PCR, polymerase chain reaction PN, projection neuron RT-PCR, reverse transcription-polymerase chain reaction SOG, subesophageal ganglion. 

Examples of receptors and ligands involved in RME. Specific gene symbols of representative human receptor and ligand proteins are listed in parentheses. TM transmembrane protein GPI glycosylphosphatidylinositol anchored protein 7TM Seven-transmembrane protein. 

Figure 22.6 Mobilization of triacylglycerols. Triacylglycerols in adipose tissue are conver ted into free fatty acids and glycerol for release into the bloodstream in response to hormonal signals. A hormone sensitive lipase initiates the process. Abbreviation 7TM. seven-transmembrane helix.

GNRP guanine nucleotide regulatory protein 7TMS seven transmembrane span... 

FIGURE 2.1 A side view of the structure of the prototype G-protein-coupled, 7TM receptor rhodopsin. The x-ray structure of bovine rhodopsin is shown with horizontal gray lines, indicating the limits of the cellular lipid membrane. The retinal ligand is shown in a space-filling model as the cloud in the middle of the structure. The seven transmembrane (7TM) helices are shown in solid ribbon form. Note that TM-III is rather tilted (see TM-III at the extracellular and intracellular end of the helix) and that kinks are present in several of the other helices, such as TM-V (to the left), TM-VI (in front of the retinal), and TM-VII. In all of these cases, these kinks are due to the presence of a well-conserved proline residue, which creates a weak point in the helical structure. These kinks are believed to be of functional importance in the activation mechanism for 7TM receptors in general. Also note the amphipathic helix-VIII which is located parallel to the membrane at the membrane interface. 

The /3-adrenergic receptor is an integral protein with seven hydrophobic regions of 20 to 28 amino acid residues that snake back and forth across the plasma membrane seven times. This protein is a member of a very large family of receptors, all with seven transmembrane helices, that are commonly called serpentine receptors, G protein-coupled receptors (GPCR), or 7 transmembrane segment (7tm) receptors. The binding of epinephrine to a site on the... 

The CaR is a member of family C II of the superfamily of seven transmembrane (7TM) receptors, also termed G protein-coupled receptors (GPCRs) (Brown and MacLeod, 2001). 7TM receptors are by far the largest group of cell surface receptors. They are very important in clinical medicine, since the 7TM receptors represent... 

Depending on the local neurochemical signaling environment and cellular receptor composition, DA likely has differential modulatory effects on distinct neurons, and cellular functions mediated by DA, therefore, might work in opposite directions (Lapish et al., 2007). The seven-transmembrane (7TM), G-protein coupled receptors for DA constitute five different receptors (D1 D2j D3j D4, and D5), that, based on their pharmacology, G-protein coupling, and structural characteristics, are divided into two major groups the I) -type (I) and D5) and D2-type (D2-D4) of receptors. In addition to distinct pharmacological profiles,... 

G-protein-coupled receptors (GPCRs), also known as seven transmembrane receptors (7TMs), are the largest known superfamily of proteins. They are involved in all types of responses to stimuli, from intercellular communication to the senses of vision, taste, and smell. They respond to diverse ligands ranging from photons (e.g., rhodopsin. Fig. 1) to small molecules (e.g., binding of epinephrine to the f52-adrenergic receptor) and... 

Seven-transmembrane-helix receptors operate in conjunction with heterotrimeric G proteins. The binding of hormone to a 7TM receptor triggers the exchange of GTP for GDP bound to the a subunit of the G protein. G proteins can transmit... 

How do our sensory systems work How are the initial stimuli detected How are these initial biochemical events transformed into perceptions and experiences We have previously encountered systems that sense and respond to chemical signals—namely, receptors that bind to growth factors and hormones. Our knowledge of these receptors and their associated signal-transduction pathways provides us with concepts and tools for unraveling some of the workings of sensory systems. For example, 7TM receptors (seven-transmembrane receptors, Section 15.1) play key roles in olfaction,... 

TM receptors (seven-transmembrane receptors. Section IS.x.x) play key roles in olfaction, taste, and vision. Ion channels that are sensitive to mechanical stress are essential for hearing and touch. 

What essential feature is carried out by the seven-transmembrane-helix receptors (7TM) ... 

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