If you wanted to use αα-amanitin to shut down 95 percent of transcription by RNA polymerase II, roughly what concentration of αα-amanitin would you use? Note that the scale on the x-axis of the graph in Question 13 is logarithmic rather than linear, so that each tick mark shows a tenfold higher concentration.
Ch. 16+17 - Transcription, RNA Processing, and Translation
All textbooks
Freeman 8th Edition
Ch. 16+17 - Transcription, RNA Processing, and Translation
Problem 16



Chapter 16, Problem 16
The primary cause of death from αα-amanitin poisoning is liver failure. Suppose a physician informs you that liver cells die because their rate of protein production falls below a level needed to maintain active metabolism. Given that αα-amanitin is an inhibitor of transcription, you wonder if this information is correct. Propose an experiment to determine whether the toxin also has an effect on protein synthesis.

1
Design an experiment with two groups of liver cells: one treated with αα-amanitin and one control group without the toxin. This will help determine if the toxin affects protein synthesis directly beyond its known effect on transcription.
Measure the baseline protein synthesis levels in both groups before introducing αα-amanitin to ensure that both groups start with similar protein production rates.
Expose the experimental group of liver cells to αα-amanitin while keeping the control group toxin-free. Maintain both groups under identical conditions to ensure that any differences observed are due to the toxin.
At various time intervals after exposure, measure the rate of protein synthesis in both groups. This can be done using radiolabeled amino acids that are incorporated into newly synthesized proteins, which can then be quantified.
Compare the protein synthesis rates between the toxin-treated and control groups. A significant reduction in protein synthesis in the αα-amanitin treated group, compared to the control group, would suggest that the toxin has a direct effect on protein synthesis, in addition to its inhibition of transcription.

Verified Solution
Video duration:
2m
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Transcription and Translation
Transcription is the process by which messenger RNA (mRNA) is synthesized from a DNA template, while translation is the subsequent process where ribosomes synthesize proteins based on the sequence of the mRNA. Understanding these processes is crucial because αα-amanitin inhibits RNA polymerase II, which is responsible for mRNA synthesis, thereby directly affecting protein production.
Recommended video:
Guided course
Review of Transcription vs. Translation
Protein Synthesis
Protein synthesis involves the creation of proteins through the processes of transcription and translation. It is essential for cell function and survival, as proteins perform a variety of roles, including enzymatic activity and structural support. A decrease in protein synthesis can lead to cell dysfunction and death, particularly in metabolically active cells like liver cells.
Recommended video:
Guided course
Proteins
Experimental Design
Experimental design refers to the planning of an experiment to test a hypothesis effectively. In this context, it involves setting up a controlled experiment to measure the effects of αα-amanitin on protein synthesis, possibly by using techniques such as Western blotting or measuring mRNA levels, to determine if the toxin impacts the translation process or the availability of mRNA.
Recommended video:
Guided course
Experimental Design Example 1
Related Practice
Textbook Question
867
views
Textbook Question
Biologists have investigated how fast pre-mRNA splicing occurs by treating cells with a toxin that blocks the production of new pre-mRNAs, then following the rate of splicing of the pre-mRNAs that were transcribed before adding the toxin. Why is addition of a toxin important in this study?
365
views
Textbook Question
The allele of the human transport protein associated with lighter skin is found almost exclusively in people with European ancestry. The other common allele for darker skin, which appears to be the ancestral allele, is found in people with African ancestry. What is a plausible explanation for how the lighter-skin allele came to be so common in those with European ancestry?
555
views