Cell-Cell Communication 4 Flashcards
Which enzyme mediates most of the effects of cAMP?
cAMP-Dependent Protein Kinase (PKA)
How is PKA Activated?
cAMP binds to the regulatory subunit, dissociation of catalytic subunit, activation and phosphorylation of other target proteins.
What is Regulatory PKA also called?
A-Kinase
What do A-Kinase anchoring proteins bind to?
Bind to A-Kinase and cytoskeleton/ organelle membranes.
What kind of G protein activates a plasma membrane bound enzyme?
Gq
What enzyme does Gq activate?
PLCβ
What phospholipid does PLCβ act on?
PIP2
PIP2, cleaved by PLCβ, produces which two 2nd messengers?
IP3 and DAG
Where in the cell do IP3 receptors bind?
ER membrane
What 2nd messenger is stored in the ER, and is released from the open channels?
Calcium
How is PKC activated?
Ca, DAG, phosphatidylserine.
After DAG is cleaved, what can it produce?
Arachidonic Acid
T/F: There is a large gradient tending to drive Ca2+ into the cytosol across those membranes.
True.
What does the Ryanodine receptor do?
Opens in response to increased calcium.
What mechanisms rapidly terminate Ca2+ signal?
Calcium pumps, calcium transporters.
