Introducing
Your new presentation assistant.
Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.
Trending searches
Three Types of Receptors:
1
Three Types of Receptors:
GPCRs
G-Proteins
Enzyme 1: adenylyl cyclase
- produces cyclic AMP
- sometimes, the G-proteins will break into alpha-GTP and beta-gamma subunits, which can then bind to other ion channels or enzymes
cAMP: activates enzymes, turns on genes
- signal ended in part by cAMP phosphodiesterase
cAMP
- primarily affects PKA (cAMP-dependent protein kinase)
Protein Kinase A
- phosphorylates serines and threonines on certain intracellular proteins
G-Protein-Coupled Receptors
Ion-Channel-Coupled Receptors
Enzyme-Coupled Receptors
- when signal binds, undergoes conformational change that causes G-protein to lose affinity for GDP, instead attach GTP, and thus be activated
G[s] = stimulates adenylyl cyclase
G[i] = inhibits adenylyl cyclase
G[q] = activates phospholipase C
Enzyme 2: phospholipase C
- produces inositol trisphosphate
- produces diacylglycerol
inositol 1,2,4 trisphosphate (IP[3]): water-soluble sugar phosphate that binds to Ca^2+ channels in the ER membrane; calcium rushes out into cytosol, signals
diacylglycerol: stays in plasma membrane; recruits and activates protein kinase C
Protein Kinase C:
- requires calcium for activation (in cytosol b/c of IP[3])
- phosphorylates some set of intracellular proteins (varies by type)
Ion-Channel Receptors:
- when signal binds, ion channel opens, allowing change in membrane potential and possible formation of action potential/electric current