Beyond the G Protein

Heptahelical Receptor Signaling: Beyond the G Protein Paradigm

H EPTAHELICAL receptors, so called because of their conserved structure featuring seven a -helical transmembrane spans, mediate physiological responses to a remarkably diverse array of stimuli. These include hormones, neurotransmitters, small peptides, proteins, lipids and ions, as well as sensory stimuli such as odorants, pheromones, bitter and sweet tastants, and photons. This superfamily of ...

G-protein Coupled Receptor Dimerization

A growing body of evidence suggests that GPCRs exist and function as dimers or higher oligomers. The evidence for GPCR dimerization comes from biochemical, biophysical and functional studies. In addition, researchers have shown the occurrence of heterodimerization between different members of the GPCR family. Two receptors can interact with each other to make a dimer through their extracellular...

4. The g Beyond Factor Analysis

Beyond the G protein: the saga of the type 2 angiotensin II receptor.

Studies of the large families of seven transmembrane receptors have focused on their signal transduction pathways initiated by their interaction with GTP activated proteins. Angiotensin II (Ang II) mediates most of its well known cardiovascular effects in conventional manner through its type 1 (AT1) receptor acting on heterotrimeric G proteins. The affinity of the type 2 (AT2) receptor specific...

The highly conserved DRY motif of class A G protein-coupled receptors: beyond the ground state.

Despite extensive study of heptahelical G protein-coupled receptors (GPCRs), the precise mechanism of G protein activation is unknown. The role of one highly conserved stretch of residues, the amino acids glutamic acid/aspartic acid-arginine-tyrosine (i.e., the E/DRY motif), has received considerable attention with respect to regulating GPCR conformational states. In the consensus view, glutami...