BIO 3153 Lecture Notes - Lecture 17: Neurotransmitter Receptor, Signal Transduction, Chemical Synapse
Document Summary
Signal molecule is bound to a cell surface. One cell expressing a ligand, another cell has the receptor for that ligand, initiates transduction of a signaling across a membrane. Factor released from one site and has effect on a target cell in another part of the organism. Signal molecules delivered to target cells by cell extensions and across chemical synapses eg neurons. 3 major classes of receptor proteins transform and extracellular binding event into and intracellular signal. Ion-channel-linked receptors (ie extracellular ligand gated ion channels, or ionotropic receptors) Transduction is in the form of a change in ion conductance. (refer to last lecture) Chemical binds to part of extracellular protein complex to open up the gate. Opens up a pathway and ions will flow: g-protein-coupled receptors (metabotropic receptors) Activates g-protein on the inside of the cell which phosphorylates other enzymes/proteins inside the cell and can go on to produce complex signals: enzyme-linked receptors (eg. gf binding, autophosphorylation)
