SC/BIOL 3130 S2 2015
Midterm 2
August 10, 2015
This exam is composed of 30 multiple-choice questions. Please answer using the scantron sheet
provided.
You are allowed 75 minutes
Good luck!
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1. Which of the following are typical features of transcriptional activators?
A.
B.
C.
D.
E.
transcription-activation domain DNA-binding domain kinase domain transcription-activation domain and DNA-binding domain transcription-activation domain and kinase domain
2. One effect of mutation or deleting the activation domain of a transcriptional activator would be:
A.
B.
C.
D.
E.
increasing histone acetylation. increased recruitment of RNA Pol II. binding of the activator to DNA, without activating transcription. reduction in the binding of the transcriptional activator to DNA. increased recruitment of RNA Pol II, without activating transcription.
3. The glucocorticoid receptor is activated by binding to:
A. its hormone ligand then moving to the nucleus. B. its hormone ligand protein partner and then moving to the nucleus.
C. its hormone partner in the nucleus. D. DNA and then to its hormone ligand. E. None of the choices are correct.
4. Which of the following are found in bZip and HLH domains?
A. leucine zipper B. helix-loop-helix regions C. zinc fingers D. leucine zipper and helix-loop-helix regions E. helix-loop-helix regions and zinc fingers
5. Insulators are DNA elements that: A. shield genes from activation by blocking enhancer activity. B. block gene activity by binding the operator regions. C. block the coding region of genes, preventing transcription. D. shield genes from activation by blocking enhancer activity and block gene activity by binding the
operator regions. E. block gene activity by binding the operator regions and block the coding region of genes,
preventing transcription.
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6. Which of the following approaches would you use to loosen the interaction of the histones with
DNA in an extract that you have prepared? A.
B.
C.
D.
E.
methylate the DNA methylate the histone acetylate the histones phosphorylate the histones phosphorylate the DNA
7. What is the most likely outcome of ubiquitination of a transcription activator such as CREB? A. It will be stimulated to bind to corepressors.
B. It will become a target for proteasomes.
C. It will be a target for chaperones.
D. It will have no effect on the activity of this protein.
E. None of the correct are correct.
8. One way to prevent the activation of certain cells by a growth factor is to
A. block phosphorylation of the cytoplasmic domain of the receptor. B. block dimerization of the receptor. C. block phosphorylation on the extracellular domain. D. block phosphorylation of the cytoplasmic domain of the receptor and block dimerization of the
receptor. E. block phosphorylation of the cytoplasmic domain of the receptor and block phosphorylation on the
extracellular domain.
9. Predict the effect of blocking GTPase activity by a mutant lacking the GAP gene. Which of the
following would be a possible outcome if cells in this mutant are treated with a growth factor? A. a sustained level of transduction B. dramatically reduced interaction of the growth factor with the receptor C. inactivation of MEK
D. dephosphorylation of the growth factor receptor E. inactivation of Elk
10. In the Ras-Raf signaling pathway, MEK phosphorylates the protein kinase ERK to activate it.
What does activated ERK do? A. phosphorylate a variety of cytoplasmic proteins B. move into the nucleus C. phosphorylate and activate several activators in the nucleus D. phosphorylate and activate Elk-1 in the nucleus E. all of the above are correct
11. CDCA7 is excluded from the nucleus by:
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A. Phosphorylation of T163
B. Binding to 14-3-3 proteins
C. Disruption of interaction with MYC
D. Masking of an NLS region
E. All of the above are correct
12. The kinase that phosphorylates T163 is
A. ERK
B. RAF
C. PI3K
D. AKT
E. PI3K
13. Inhibition of PI3K would result in:
A. Cytoplasmic CDCA7
B. Decreased MYC binding to CDCA7
C. Increased T163 phosphorylation
D. Reduced apoptosis
E. None of the above are correct
14. MYC binds to a consensus sequence of DNA called:
A. F boxes
B. E boxes
C. Enhancers
D. Insulators
E. All of the above are correct
15. Activation of MYC in the absence of growth signals causes
A. Cell cycle withdrawal
B. Apoptosis
C. Necrosis
D. enhanced growth
E. None of the above are correct
16. At least 20% of all amino acids found in histones are the basic amino acids
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A. glycine or serine.
B. arginine or lysine. C. tryptophane or tyrosine. D. valine or praline. E. cysteine or isoleucine.
17. One method used by researchers to demonstrate the existence of nucleosome free DNA regions
is A. Chromatin IP experiments.
B. Restriction analysis. C. Reporter gene experiments. D. Anion Exchange chromatography.
E. DNase hypersensitivity experiments.
18. Addition of core histones + 0.5 histone H1/Nuc would:
A. Decrease the activation of GAL4-VP16-dependent transcription of the E4 gene compared to core
histone alone
B. Increase the activation of GAL4-VP16-dependent transcription of the E4 gene compared to core
histone alone
C. Have no effect on the activation of the GAL4-VP16-dependent transcription of the E4 gene
compared to core histone alone
D. Increase the basal level of E4 gene transcription
E. None of the above are correct
19. Acetylation of H4K8 within the INF-beta promoter occurs
A. After acetylation of H3K14
B. Before TBP binding
C. After mRNA appearance
D. Before viral infection
E. None of the above are correct
20. In the INF-beta promoter, mutation of H3K14 to A14 would:
A. Prevent BRG1 association
B. Prevent TAF1 association
C. Prevent H4K8 acetylation
D. Prevent H3S10 phosphorylation
E. All of the above are correct
21. One method for analyzing the acetylation state of H4K12 within the INF-beta promoter would be:
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A. PCR analysis
B. Chromatin immunoprecipitation
C. In vitro transcription
D. Western blotting
E. Primer extension
22. Histone acetylation can occur in the A.
B.
C.
D.
E.
nucleus. cytoplasm. ER lumen. nucleus and cytoplasm. nucleus, cytoplasm, and ER lumen.
23. Which of the following molecules can expedite RNA Pol II elongation through a nucleosome? A. HAT B. FALSE C. IFN-beta
D. TRUTH
E. FACT
24. The Histone Code states that the A. primary sequence of the histone proteins never changes over time. B. combination of histone modification on a given nucleosome near a gene's control region affects the
efficiency of transcription of all the nearby genes.
C. combination of histone modification on a given nucleosome near a gene's control region affects the
efficiency of transcription of that gene. D. lysines are the only amino acids found in histones that can be acetylated and deacetylated. E. histones are found in all living cells.
25. Which of the following is not true concerning eukaryotic mRNA processing? A. addition of a 3 poly-A tail B. addition of a 5 cap C. intron splicing D. occurs in the nucleus E. occurs in the cytoplasm
(yes, I did mention 3’ poly A-tail and 5’ capping in lecture)
26. The first two bases and the last two bases in the splicing signal consensus sequence are A. GT-AG. 6
B. GU-AC. C. CU-AG. D. GU-AG.
E. GT-TG.
27. Which of the following is the name for the Yeast 40S particle where mRNA modification takes
place? A.
B.
C.
D.
E.
polysome proteosome spliceosome enhancesome transcriptome
28. The splicing machinery is composed of A. RNA.
B. protein.
C. DNA. D. RNA and protein. E. RNA, protein, and DNA
29. HAT A activity occurs in the:
A. Cytoplasm
B. Nucleus
C. Golgi bodies
D. Endosomes
E. Proteosomes
30. Activation of HDAC generally:
A. Represses gene activity
B. Increases histone acetylation
C. Prevents looping of DNA
D. enhances RNA polymerase II binding
E. None of the above are correct
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