GPCR: What would the following mutation mean for the status of the signaling pathway, and the generation of cAMP from ATP? 1) G-protein coupled receptor (GPCR) Loss of Function, in combination with Gain of function of PKA catalytic subunitsa) Pathway ON (final output achieved)b) Pathway OFF (no final output)c) cAMP generatedd) cAMP not generated 2) G-protein coupled receptor (GPCR) Gain of Function, in combination with Loss of function of PKA catalytic subunitsa) Pathway ON (final output achieved)b) Pathway OFF (no final output)c) cAMP generatedd) cAMP not generated

GPCR: What would the following mutation mean for the status of the signaling pathway, and the generation of cAMP from ATP? 1) G-protein coupled receptor (GPCR) Loss of Function, in combination with Gain of function of PKA catalytic subunitsa) Pathway ON (final output achieved)b) Pathway OFF (no final output)c) cAMP generatedd) cAMP not generated 2) G-protein coupled receptor (GPCR) Gain of Function, in combination with Loss of function of PKA catalytic subunitsa) Pathway ON (final output achieved)b) Pathway OFF (no final output)c) cAMP generatedd) cAMP not generated

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 5RE: Second-messenger systems ultimately bring about the desired cell response by inducing a change in...

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Second-messenger systems ultimately bring about the desired cell response by inducing a change in the shape and function of particular designated intracellular proteins. (True or false?)
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You are studying a drug that affects a cAMP signalling pathway that is normally initiated when a signalling molecule binds to a G-protein coupled receptor. You determine that the drug prevents the hydrolysis of GTP bound to G-proteins in this pathway. Describe the impact, if any, that this drug would have on the G-protein coupled receptor (GPCR), assuming that the pathway has been activated by the presence of the signalling molecule (first messenger). Include an explanation for your response.
Activation of certain GPCRs triggers an intracellular signaling mechanism that involves activation of adenlyl cyclase and an increase of cAMP. Which of the following statements best describes the the events that follow such a cAMP increase? a.) The cAMP increase leads to activation of protein kinase C. b.) The cAMP increase leads to activation of the release of the gamma subunit from the GPCR. c.) The cAMP increase leads to activation of protein kinase A.
Working out the order in which the individual components in a signaling pathway act is an essential step in defining the pathway. Imagine that two protein kinases, PK1 and PK2, act sequentially in a kinase cascade. When either kinase is completely inactivated, cells do not respond to the normal extracellular signal. By contrast, cells containing a mutant form of PK1 that is permanently active respond even in the absence of an extracellular signal. Double mutant cells that contain inactivated PK2 and permanently active PK1 respond in the absence of a signal. Draw out the signaling pathway in a wild-type cell. What outcome is predicted for a double mutant cell with an activating mutation in PK2 and an inactivating mutation in PK1? Explain your reasoning
Someone goes for a jog first thing in the morning and encounters a squadron of javelinas, causing a release of epinephrine. Some of this circulating epinephrine binds to a G-alpha-s coupled receptor (GPCR) on the surface of muscle cells. Which of the following would occur in the muscle cell as a result of this activation? Nitric oxide synthesis would increase. cyclic AMP (cAMP) activity would increase. Phospholipase C (PLC) would hydrolyze (cut) the molecule PIP2. The levels of adenylate cyclase activity would decrease. The levels of adenylate cyclase activity would decrease. Which ligand is CORRECTLY matched with its characteristic? Group of answer choices Glucagon: stimulates the activation of the mitogen activated protein (MAP) kinase pathway Nitric oxide (NO): must bind to its target protien withn a few seconds because NO degrades rapidly Steroid hormone: produces a response in its target cells within seconds Acetylcholine: hydrophobic molecule that binds to…
Briefly explain how integrin inside-out and outside-in signaling is different structurally and functionally? (hint: explain what happened to ligand binding and conformation)
Much of what we know about cell signalling comes from biochemical studies of proteins isolated in test tubes. What is the precise quantitative behaviour of intracellular signalling networks in an intact cell where countless other signals and cellular components can influence the specificity and intensity of signalling?
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