PHAR2210 Lecture Notes - Lecture 10: Adenylyl Cyclase, Heterotrimeric G Protein, Prostanoid
Document Summary
Largest superfamily of transmembrane receptors largest single class of targets for therapeutic drugs: neurotransmitters, hormones, opioids, amines, peptides, proteins, light-sensitive compounds, odours. Interact with heterotrimeric g proteins: gtp- and gdp-binding proteins, activate signal transduction pathways, adenylate cyclase, phospholipase c, phosphodiesterase ion channels. 5-hydroxytryptamine receptors: acetylcholine receptors (muscarinic, adrenoceptors, dopamine receptors. Endothelin receptors: gabab receptors, histamine receptors, opioid receptors, vip and pacap receptors, details: Location: membrane: 7-transmembrane domains: effector: enzyme or channel, respond to: hormones and slow neurotransmitters. Comprise 3 subunits: , , : the -subunit binds gtp and has gtpase activity. 2-adrenoceptor: extracellular n-terminus, 7 transmembrane -helices, 3 extracellular and 3 intracellular loops. Intracellular c-terminal tail: time scale: seconds, fast, examples: adrenoceptors, muscarinic ach receptors, activation of adenylate cyclase, g dissociates from g , g binds to adenylate cyclase, adenylate cyclase cyclisation of atp to camp. Inactivation of g protein: gtp hydrolysed to gdp, g dissociated from adenylate cyclase, g binds to g .
