1) One cell-signaling pathway implicated in the regulation of cell division is the mTOR/Akt pathway. 'TOR is a protein that stimulates the translation of other proteins, which is an important requirement for cell division. In the absence of growth factor signals from the cell's environment, the proteins TSC1 and TSC2 will physically bind to each other, which allows them to inhibit mTOR from functioning. However, when membrane receptors do encounter certain growth factors from the environment, they will result in the activation of a protein called Akt. Once activated, Akt will phosphorylate TSC2, preventing it from being able to physically bind to TSC1.

1) One cell-signaling pathway implicated in the regulation of cell division is the mTOR/Akt pathway. 'TOR is a protein that stimulates the translation of other proteins, which is an important requirement for cell division. In the absence of growth factor signals from the cell's environment, the proteins TSC1 and TSC2 will physically bind to each other, which allows them to inhibit mTOR from functioning. However, when membrane receptors do encounter certain growth factors from the environment, they will result in the activation of a protein called Akt. Once activated, Akt will phosphorylate TSC2, preventing it from being able to physically bind to TSC1.

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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