Concept explainers
(a)
Interpretation:
The function of Csk as tumor-suppressor gene or a proto-oncogene is to be determined.
Concept introduction:
Tumor suppressor genes that are responsible for regulating cell growth and division, repair DNA, and regulates apoptosis. Any mutation in the tumor suppressor gene can lead to uncontrolled cell division, ultimately resulting in cancer. Any normal gene upon mutation leading to a cause of cancer is termed as the proto-oncogene. The proto-oncogene upon permanent activation leads to cancer, while tumor suppressor gene upon inactivation causes cancer.
(b)
Interpretation:
The function of PTP1B as tumor-suppressor gene or a proto-oncogene is to be determined.
Concept introduction:
Tumor suppressor genes that are responsible for regulating cell growth and division, repair DNA, and regulates apoptosis. Any mutation in the tumor suppressor gene can lead to uncontrolled cell division, ultimately resulting in cancer. Any normal gene upon mutation leading to a cause of cancer is termed as the proto-oncogene. The proto-oncogene upon permanent activation leads to cancer, while tumor suppressor gene upon inactivation causes cancer.
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BIOCHEM-ACHIEVE(FIRST DAY DISCOUNTED)
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- Many enzymes can hydrolyze GTP between the β and γ phosphates. The GTP analog β,γ-imidoguanosine 5′-triphosphate (Gpp(NH)p), shown below, cannot be hydrolyzed between the β and γ phosphates. Predict the effect of microinjection of Gpp(NH)p into a myocyte on the cell’s response to β-adrenergic stimulation.arrow_forwardThe Luteinizing hormone receptor (LHR) is a GPCR that predominantly couples to Gαs (G alpha s) G proteins in response to binding of the endogenous ligand luteinizing hormone (LH). Briefly describe how activation of this receptor ultimately leads to protein kinase A (PKA) activation.arrow_forwardRTKs are receptors made of an extracellular ligand binding domain and an intracellular kinase domain (see image). Insulin binds to its RTK Insulin receptor, causing an increase in glucose absorption and storage in liver cells. EGF binds to its own RTK, EGFR and promotes cell growth through the Ras pathway. a) Explain why the same type of tyrosine kinase in two RTKs can lead to very different cellular responses. Give an example of potential cellular outputs for each of these two RTKs.arrow_forward
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