Final Exam - Intracellular Signaling Flashcards
What is the general mechanism of the activation of G proteins?
G Protein coupled receptor
How are G proteins activated?
by GTP binding to the alpha subunit which then activates the beta and gamma subunits
What does histamine bind to and what does this binding result in?
binds to the H1 receptor and the alpha subunit exchanges GDP for GTP
What does GTP activate within the histamine response?
phospholipase C (PLC)
What does increased calcium do within the histamine response?
activates the protein receptor kinase C which leads to biological activities
What are the symptoms of a histamine response?
histamine is released which leads to vasodilation which leads to endothelial gapping which leads to fluid leakage which leads to swelling
What is the general mechanism of enzyme linked receptors?
they have a kinase, either a part of them or associated with them
How are enzyme linked receptors activated?
when the kinase is close to the enzyme link receptors, they attach and cross phosphorylation initiates activity
What are molecular switches?
phosphorylation via kinase
How are molecular switches activated?
the exchange of GDP for GTP
What is ras?
a protein that activates the MAP kinase cascade
When is ras incactive?
when GDP is bound
How do you activate ras?
GDP is knocked off by accessory proteins and GTP binds
How do you deactivate ras?
GTP is hydrolyzed and GDP rebinds to the protein
How does a toll-like receptor function?
cause molecules to come together which activates a cascade which activates NFkB and jun/fos
