When adrenaline (epinephrine) binds to adrenergic receptors on the surface of a muscle cell, it activates a G protein, initiating a signaling pathway that results in the breakdown of muscle glycogen. How would you expect glycogen breakdown to be affected if muscle cells were injected with a nonhydrolyzable analog of GTP, that can’t be converted to GDP? Consider what would happen in the absence of adrenaline and after a brief exposure to it.

When adrenaline (epinephrine) binds to adrenergic receptors on the surface of a muscle cell, it activates a G protein, initiating a signaling pathway that results in the breakdown of muscle glycogen. How would you expect glycogen breakdown to be affected if muscle cells were injected with a nonhydrolyzable analog of GTP, that can’t be converted to GDP? Consider what would happen in the absence of adrenaline and after a brief exposure to it.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter9: Cell Communication

Section9.4: Signaling Pathways Triggered By Internal Receptors

Problem 1SB: What distinguishes a steroid receptor from a receptor tyrosine kinase receptor or a...

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Why is the GTPase activity of G proteins crucial to the proper functioning of a cell? Propose a theory as to why G proteins have not evolved to catalyze GTP hydrolysis more efficiently.
Why is the GTPase activity of G proteins crucial to the proper functioning of a cell? Why have G proteins not evolved to catalyze GTP hydrolysis more efficiently?
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