G proteins couple receptors of extracellular signals to intracellular signaling pathways. The G protein alpha subunit binds guanyl nucleotide and is a weak GTPase. A set of residues that are unique to G-alpha as compared to its ancestor the Arf-like ...
G proteins couple receptors of extracellular signals to intracellular signaling pathways. The G protein alpha subunit binds guanyl nucleotide and is a weak GTPase. A set of residues that are unique to G-alpha as compared to its ancestor the Arf-like family form a ring of residues centered on the nucleotide binding site [3]. A Ggamma is found fused to an inactive Galpha in the Dictyostelium protein gbqA [3].
G-protein gamma like domains (GGL) are found in the gamma subunit of the heterotrimeric G protein complex and in regulators of G protein signaling (RGS) proteins [1]. It is also found fused to an inactive Galpha in the Dictyostelium protein gbqA [2] ...
G-protein gamma like domains (GGL) are found in the gamma subunit of the heterotrimeric G protein complex and in regulators of G protein signaling (RGS) proteins [1]. It is also found fused to an inactive Galpha in the Dictyostelium protein gbqA [2]. G-gamma likely shares a common origin with the helical N-terminal unit of G-beta [2]. All organisms that posses a G-beta possess a G-gamma [2].
Amino terminal of the G-protein receptor rhodopsin
Rhodopsin is the archetypal G-protein-coupled receptor. Such receptors participate in virtually all physiological processes, as signalling molecules. They utilise heterotrimeric guanosine triphosphate (GTP)-binding proteins to transduce extracellular ...
Rhodopsin is the archetypal G-protein-coupled receptor. Such receptors participate in virtually all physiological processes, as signalling molecules. They utilise heterotrimeric guanosine triphosphate (GTP)-binding proteins to transduce extracellular signals to intracellular events. Rhodopsin is important because of the pivotal role it plays in visual signal transduction. Rhodopsin is a dimeric transmembrane protein and its intradiskal surface consists of this amino terminal domain and three loops connecting six of the seven transmembrane helices. The N-terminus is a compact domain of alpha-helical regions with breaks and bends at proline residues outside the membrane [1]. The transmembrane part of rhodopsin is represented by 7tm_1 (Pfam:PF00001). The N-terminal domain is extracellular is and is necessary for successful dimerisation and molecular stability [2].
