NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
by
Sigrid A. Carle
Biology Department
Hobart and William Smith Colleges,
Geneva, NY
Team Members Names: __________________________________________________________
_______________________________________________________________________________
Questions (Answer the following questions as a team, save file as a pdf and upload to Gradescope).
1. Define epigenetic inheritance.
2. Define chromatin.
3. Name three mechanisms used by eukaryotic cells to modify chromatin, which can initiate epigenetic change?
4. Based on Dr. Crab’s treatment plan, specifically, which mechanism that you identified in Question 3 is most
likely to play a role in the development of Wiggles’ lymphoma?
5. Explain how chromatin remodeling control gene expression.
“Wiggles Isn’t Wiggling: Gene Expression Edition” by Sigrid A. Carle
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
6. How does chromatin remodeling relate to cancer (oncogenesis)?
7. Which RNA polymerase most likely transcribes p21 and Apaf-1 genes? Explain your answer.
8. State three characteristics of the core promoter for protein coding genes.
9. State three characteristics of enhancer regions for protein coding genes.
10. Enzymes called HATs (histone acetyltransferases) and HDACs regulate histone acetylation. Explain how
histone acetylation within a promoter helps facilitate the expression of a gene.
11. Make a simple drawing of the p21 gene (CDKN1A) that shows the arrangement from 5ʹà 3ʹ of introns, exons
(assume there are 4), and the regulatory elements (include 3) in the gene that are described in Q8-9. On your
drawing also indicate where an activator protein, RNA polymerase II, and the general transcription factors
would bind, and label the start of transcription as +1.
“Wiggles Isn’t Wiggling: Gene Expression Edition” by Sigrid A. Carle
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
12. Based on the results in Figure 1, is Xyzi or QB more effective at inhibiting HDAC 1? Explain your answer.
Xyzi
QB
Figure 1. The effect of potential HDACi on HDAC 1 activity. Relative HDAC activity is
calculated by dividing the amount of product produced in the presence of the potential
HDACi by the amount produced without the potential inhibitor. One hundred percent
activity means the potential inhibitor did not inhibit HDAC 1.
13. In a follow-up experiment, Alice determined that Xyzi killed cancer cells at a lower concentration than QB.
Based on the results in Figure 1, why is it not surprising that Xyzi kills cancer cells at lower concentrations than
QB?
14. On the next page, write a one-page letter to Claire (Mom) explaining whether or not Wiggles should be treated
for lymphoma. Include the following in your letter:
a. What is the average age at which dogs are diagnosed with lymphoma? Compare this to the life expectancy
of a golden retriever.
b. What is the treatment for lymphoma?
c. What is the expected survival rate after treatment?
“Wiggles Isn’t Wiggling: Gene Expression Edition” by Sigrid A. Carle
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NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE
“Wiggles Isn’t Wiggling: Gene Expression Edition” by Sigrid A. Carle
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