GPCRs

Question 0

G alpha i stimulated by

Answer 0

PGE1

Adenosine

Question 1

G alpha s stimulated by

Answer 1

ACTH
Glucagon
Epinephrine

Question 2

Acetylcholine binds ________________ receptor = activates _________________ effector protein estimating in cellular ___________ and __________________.

Effector from activated by G alpha or G beta gamma?

Answer 2

Muscarinic, K+ channel
Hyperpolarization,
slows rate of heart muscle contraction

G beta gamma

Question 3

cAMP activates

Answer 3

PKA

Question 4

cGMP activates

Answer 4

PKG

Opens cation channels in rod cells

Question 5

DAG diacylglycerol activates

Answer 5

PKC

Question 6

IP3 opens

Answer 6

Ca2+ channels in endoplasmic reticulum

Question 7

Which G proteins activate PLC(beta)?

Answer 7

G alpha naught

G alpha q

Question 8

Pathway that leads to DAG+ IP3?

Answer 8

Phosphatidylinositol PI-> PI 4 phosphate -> PIP2 (PI 4,5- bisphosphate) -> IP3+ DAG

Last rxn preformed by phospholipase C beta

Question 9

4 modes if herceptin action

Answer 9

1. Prevents EGF ligand binding to receptor
2. Prevents dimerization heterodimer
3. Prevents cleavage of extra cellular domain (high Her2 =dimerization= activate pathway so protease cleaved off extracellular domain= hyperactivation )
4. Activate immune response, which can then trigger a response to cancer cells

Question 10

Herceptin

Answer 10

Monoclonal antibody mAb drug

Targets high Her2(RTK) expression in breast cancer

Question 11

SH2

Answer 11

Src homology 2 domain
Sarcoma
Binds phosphotyrosine e.g on RTK

Question 12

SH3

Answer 12

Binds prolong e.g 2 SH3 on GRB2 bind SOS GEF

Question 13

GRB2

Answer 13

Growth factor receptor bound protein

Adaptor protein

Question 14

Viral Src

Answer 14

Like normal: myr SH3 SH2 kinase domains

BUT missing carboxy terminus that contains regulatory Y527, inhibitory P by csk

Therefore constitutively active

Question 15

PTB

Answer 15

Phosphotyrosine binding domain

Multi-docking protein

Question 16

IRS-1

Answer 16

Insulin receptor substrate protein

Contains PTB
multi-docking protein= recruit other adapter proteins

Question 17

Ras

Answer 17

Molecular switch 
Monomeric G protein 
GTPase switch protein 
Lipid anchored to PM 
Low GTPase activity 
Not linked directly to cell surface receptor 
Similar to G alpha but smaller 
Regulated by GEFs and GAPs

Mutation in G12 prevents GAP binding = cancer bc constitutively on

Question 18

Which is not only a serine theronine kinase?

Raf
MEK
MAPK

Answer 18

MEK

Also P tyrosine