Cell-Cell Communication 5 Flashcards
How can GPCRs regulate ion channels?
Activate or Inactivate ion channels- alter ion permeability and electrical excitability.
T/F: Growth factors and insulin act through RTK.
True.
What is the domain that binds phosphorylated tyrosines in the receptor
SH2 domain
What does Insulin Receptor Substrate 1 (IRS1) do?
Associates with phosphorylated tyrosines on the activated receptor, and creates more docking sites.
What does PI3-kinase do?
Phosphorylates lipids, and produces lipid docking sites in the PM to attract signaling proteins, and activates its pathway.
How can PI3-kinase be activated?
By GPCRs or RTKs.
T/F: PI3-kinase does not play a central role in cell survival and growth.
False; it does.
What is the name of the pathway that insulin uses?
PI3-kinase-Akt Pathway
T/F: After activation, PI3-kinase phosphorylates PIP2 in the PM, into PIP3.
True.
Which two enzymes does PIP3 recruit?
PDK1 and Akt.
What is another name for Akt?
Protein kinase B (PKB).
What are 2 important facts about PIP3?
Serves as a docking site for various intracellular proteins, and it is a second messenger.
What do phosphoinositide phosphatases do?
They can dephosphorylate and inactivate PIP3.
How is Akt activated?
Activated by PDK1 and PIP3 together.
Once activated, what can Akt do?
Akt phosphorylates target proteins at the PM, cytosol and nucleus. Enhance cell growth and survival.
