BIOL 2021 Lecture Notes - Lecture 14: G Protein–Coupled Receptor, Phosphatidylinositol (3,4,5)-Trisphosphate, Protein Kinase
Feb 27th (Lecture 13)
• Back to the classification of receptors, PM receptors: ligand binds to receptor on
the outside:
o Ion channels, eg, neurotransmitters bind to transmitter gated ion channels.
o G protein coupled receptors:
▪ 1. Enzyme targets produce second messengers, eg: cAMP>
activates PKA, IP3 and DAG > activate PKC, Ca2+ > activates
calmodulin.
▪ 2. Targets are ion channels, eg: rod photoreceptors.
o Enzyme coupled receptors: ligand binding causes activation of enzyme
activity
▪ 1. Tyrosine kinases: receptor tyrosine kinases or tyrosine kinase
associated receptors.
▪ 2. ser/thr kinases.
▪ 3. Histidine kinases and many others.
o Miscellaneous.
• Intracellular receptors
o Ligands are gases
o ligands...
• Fig 15-55 parallel intracellular signaling pathways:
o GPCRs and RTKs can activate some responses, RTK can activate
phospholipase C → IP3 and DAG, or Grb 2 → Ras → MAPKKK →
MAPKK → MAPK, or PI 3-kinase → PI(3,4,5)P3 → PDK1.
o Can activate several different responses,
o Everything on this figure we have gone through. So you should know
everything.
find more resources at oneclass.com
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Document Summary
Feb 27th (lecture 13: back to the classification of receptors, pm receptors: ligand binds to receptor on the outside: Ion channels, eg, neurotransmitters bind to transmitter gated ion channels: g protein coupled receptors, 1. Enzyme targets produce second messengers, eg: camp> activates pka, ip3 and dag > activate pkc, ca2+ > activates calmodulin: 2. Targets are ion channels, eg: rod photoreceptors: enzyme coupled receptors: ligand binding causes activation of enzyme activity, 1. Tyrosine kinases: receptor tyrosine kinases or tyrosine kinase associated receptors: 2. ser/thr kinases, 3. Intracellular receptors: ligands are gases ligands, fig 15-55 parallel intracellular signaling pathways, gpcrs and rtks can activate some responses, rtk can activate phospholipase c ip3 and dag, or grb 2 ras mapkkk . Mapkk mapk, or pi 3-kinase pi(3,4,5)p3 pdk1: can activate several different responses, everything on this figure we have gone through. So you should know everything: question: ras can activate both the mapk pathway and the pi3-kinase pathway.