Exam 8: Cell Signaling Systems

An estrogen-dependent breast cancer cell line is grown in a medium that contains estrogen. Cell proliferation is monitored over time. In a separate experiment, the cell line is grown in a medium that lacks estrogen but includes bisphenol A, a compound found in polycarbonate plastics. When monitored, cell proliferation is higher than in the presence of estrogen. A possible explanation of these results is that bisphenol A

First messengers, but NOT second messengers

A mutation causes a cell to divide uncontrollably. Analysis of the cell shows that both copies of the gene must have the mutation. From this information, it can be determined that the mutation is

A response element is

Define the main characteristics of a signal transduction pathway and give a specific example of such a pathway.

Which class of proteins interacts with a heterotrimeric intracellular protein?

Explain why the retinoblastoma gene is considered a tumor suppressor.

Caspases contain

Which scenario would allow $\beta$ -arrestin to bind to the GPCR?

Which of the following prevents GPCR from reassociating with the G _{$\alpha$ $\beta$ $\gamma$} complex?

Which of the following acts as a transcription factor in the cell survival pathway activated by TNF- $\alpha$ ?

Which of the following is true of procaspase 8?

Estradiol is secreted by the ovaries, travels through the bloodstream, and interacts with estrogen receptors on breast epithelial cells. In this scenario estradiol is acting through which type of mechanism?

Nuclear receptors are ligand-activated transcription factors that control a wide range of physiologic responses. The responses are governed by cell-specific expression of nuclear receptors and coregulatory proteins and accessibility of target gene DNA sequences. What else governs the responses?

The result of TRADD proteins binding to TNF receptors is that

A class of proteins that assist other proteins to fold are known as proteins.

Which protein is part of the TNF receptor-activated programmed cell death signaling pathway?

Predict how the flux of glucose through glucose transporters will change when PI-3K is activated.

On insulin binding to the insulin receptor, MAP kinase signaling proteins are activated. Which of the following proteins are part of this signaling pathway?

Below shows the cell survival pathway promoted by TNF- $\alpha$ . A complex is indicated with a question mark. What is this complex?