W3: Signal Transduction Flashcards
Beta adrenergic receptor (B AR) is an example of ____, activated by ligands ___ (___).
GPCR, epinephrine (adrenaline)
Epinephrine (adrenaline) causes physiological changes such as ___ and ___.
Increased CO, bronchodilation
Selectivity: low affinity of ligand-receptor means low/high Kd (dissociation constant).
high
Isopreterenol is an agonist/antagonist drug that activates/blocks beta adrenergic receptor (B AR).
Agonist (like epinephrine/adrenaline), activate
medication used for the treatment of bradycardia (slow heart rate), heart block, and rarely for asthma. It is a non-selective β adrenoreceptor agonist that is the isopropylamine analog of epinephrine (adrenaline). (Wikipedia)
Propranolol is an agonist/antagonist drug that activates/blocks beta adrenergic receptor (B AR).
Antagonist, block
“Propranolol is a beta-blocker used to treat high blood pressure, irregular heartbeats, shaking (tremors), and other conditions”
In B AR signaling, second messenger ____ is made by effector protein ___ ___.
cAMP, Adenylyl cyclase
In B AR signaling, adenylyl cyclase is activated by ___ attached to GDP/GTP.
G-protein, GTP
List five mechanisms of attenuation of B AR signaling
1) Return from GTP to GDP (hydrolysis by GAP)
2) Reduce cAMP to AMP (phosphodiesterase)
3) Inactivate PKA
4) Receptor desensitization (modify receptor)
5) Ligand-receptor degradation (endocytosis)
PTH is released when parathyroid detects low/high blood calcium level
low
PTH acts on ___ and ___ to increase/decrease blood calcium.
Kidney, bone, increase
Hypoparathyroidism is when there is low/high Ca2+, low/high PTH. Causes are ____, ____.
Low, low; parathyroid damage, congenital
When calcium is low, PTH is supposed to go up. This means parathyroid is malfunctioning.
Hypoparathyroidism causes symptoms like ___, ___, ___ and can be treated with ____, ____.
Cramping, twitching, spasms;
Ca2+ supplement, vitamin D
Pseudohypoparathyroidism: low/high Ca2+, low/high PTH
Low, high
This means PTH production is working correctly but signaling is not.
Haploid sufficiency; one copy mutation (G alpha gene), presentation is less than normal; half as much protein so more PTH won’t help
Nicotine/Ach receptor (NR) is an example of ___, whose ligand is ___ (or ___).
Ligand-gated ion channel receptor, Ach (or nicotine)
Autoimmune disease that destroys Nicotine/Ach receptors is called ___ ___.
Myasthenia gravis
The most common type of enzyme-linked (catalytic) receptor is ___.
RTK - receptor tyrosine kinase
Brain cancer (glioblstoma multiforme) can be caused by ___, a RTK. Treatment can be administering ____ ____ drug.
EGFR - epidermal growth factor receptor; EGFR inhibitor
What is RAS and what pathway is it involved in?
RAS is a regulated GTPase in RTK pathway.
What connects phosphorylated RTK and GEF?
Adaptor protein
lack any intrinsic enzymatic activity themselves, instead mediating specific protein-protein interactions that drive the formation of protein complexes (Wikipedia)
RAS regulation:
GTP –> GDP by ___ (inactivate)
GAP: GTPase Accelerating Protein
RAS regulation:
GDP dissociated by ___ (lead to activation of RAS)
GEF - Guanine nucleotide Exchange Factor
Feedback signaling: FSH produced in (A) and act on (B) cell, which produces estrogen. Estrogen inhibits A from producing FSH.
A. Pituitary gland
B. Ovarian follicular cells
Glycogenesis is facilitated by enzyme ____ ____, which is activated/inhibited by GSK by default (without insulin).
Glycogen synthase, inhibited
In the presence of insulin, AKT is activated and ultimately activates/deactivates glycogen synthase.
activates
