Expression and GTP sensitivity of peptide histidine isoleucine high-affinity-binding sites in rat
Colin Debaigt1, Annie-Claire Meunier, Stephanie Goursaud
1IPBC CNRS-UMR 6187 Pôle Biologie Santé, 40 avenue du Recteur Pineau, 86022 Poitiers Cedex, France.
Abstract:
High-affinity-binding sites for the vasoactive intestinal peptide (VIP) analogs peptide histidine/isoleucine-amide (PHI)/carboxyterminal methionine instead of isoleucine (PHM) are expressed in numerous tissues in the body but the nature of their receptors remains to be elucidated. The data presented indicate that PHI discriminated a high-affinity guanosine 5'-triphosphate (GTP)-insensitive-binding subtype that represented the totality of the PHI-binding sites in newborn rat tissues but was differentially expressed in adult animals. The GTP-insensitive PHI/PHM-binding sites were also observed in CHO cells over expressing the VPAC2 but not the VPAC1 VIP receptor.
Related Concept Videos
Activation and Inactivation of G Proteins
Rab Proteins
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
GTPases and their Regulation
Large G-proteins, also known...
Small GTPases - Ras and Rho
Three regulatory proteins control their activity:
IP3/DAG Signaling Pathway
G-protein Coupled Receptors


