Two protein kinases, barley kinase and hops kinase, function sequentially in an intracellular signaling pathway. If either kinase contains a mutation that permanently inactivates it, no response is seen in cells when an extracellular signal is received. A mutation that permanently activates barley results in a response even when there is no extracellular signal. You characterize a double mutant in which hops has the inactivating mutation and barley has the activating mutation. You observe that a response is seen in the double mutants even in the absence of an extracellular signal. In the normal signaling pathway, does barley phosphorylate hops or does hops phosphorylate barley? Briefly explain your answer.

Two protein kinases, barley kinase and hops kinase, function sequentially in an intracellular signaling pathway. If either kinase contains a mutation that permanently inactivates it, no response is seen in cells when an extracellular signal is received. A mutation that permanently activates barley results in a response even when there is no extracellular signal. You characterize a double mutant in which hops has the inactivating mutation and barley has the activating mutation. You observe that a response is seen in the double mutants even in the absence of an extracellular signal. In the normal signaling pathway, does barley phosphorylate hops or does hops phosphorylate barley? Briefly explain your answer.

Biology 2e

2nd Edition

ISBN:9781947172517

Author:Matthew Douglas, Jung Choi, Mary Ann Clark

Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark

Chapter9: Cell Communication

Section: Chapter Questions

Problem 1VCQ: Figure 9.8 HER2 is a receptor tyrosine kinase. In 30 percent of human breast cancers, HER2 is...

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If you have a protein kinase that is regulated by both small molecule inhibitors as well as by phosphorylation, and is part of a cooperative enzyme complex that works as part of a larger pathway involving kinase and GTPase proteins please explain where on this protein regulation could occur, how different types of inhibition could control the function of the protein as well as the function of the complex, and how the protein could regulate other proteins. (This question was previously answered but it was answered incompletely mentioning an herbicide developed in the 1950's. Apparently, it was a plagiarized excerpt from an NCBI article. This is a repost for a full and complete answer. Thank you so much for your help! :) )
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