BIO 351 EXAM 2 (Prac Quiz Control of Gene Expression)

A neuron and a white blood cell have very different functions. For example, a neuron can receive and respond to electrical signals, while a white blood cell defends the body against infection. This is because:

Investigators performed nuclear transplant experiments to determine whether DNA is altered irreversibly during development. Which of the following statements about these experiments is TRUE?

The distinct characteristics of different cell types in a multicellular organism result mainly from the differential regulation of the

The human genome encodes about 21,000 protein-coding genes. Approximately how many such genes does the typical differentiated human cell express at any one time?

Which of the following is not a good example of a housekeeping protein?

Which of the following statements about differentiated cells is TRUE?

Which of the following statements about transcriptional regulators is FALSE?

Operons

The tryptophan operator

Which of the following statements about the Lac operon is FALSE?

What do you predict would happen if you replace the Lac operator DNA from the Lac operon with the DNA from the operator region from the tryptophan operon?

You are interested in examining the Psf gene. It is known that Psf is normally produced when cells are exposed to high levels of both calcium (Ca2+) and magnesium (Mg2+). MetA, MetB, and MetC are important for binding to the promoter of the Psf gene and are involved in regulatingits transcription. MetA binds to the "A" site in the promoter region, MetB to the "B" site, and MetC to the "C" site. You create binding-site mutations in the A, B, and C sites and observe what happens to transcription of the Psf gene. Your results are summarized in Table above.
From the table above which of the following proteins are likely to act as gene activators?

You are interested in examining the Psf gene. It is known that Psf is normally produced when cells are exposed to high levels of both calcium (Ca2+) and magnesium (Mg2+). MetA, MetB, and MetC are important for binding to the promoter of the Psf gene and are involved in regulating its transcription. MetA binds to the "A" site in the promoter region, MetB to the "B" site, and MetC to the "C" site. You create binding-site mutations in the A, B, and C sites and observe what happens to transcription of the Psf gene. Your results are summarized in Table below.
Which of the following proteins are likely to act as gene repressors?

You are interested in examining the Psf gene. It is known that Psf is normally produced when cells are exposed to high levels of both calcium (Ca2+) and magnesium (Mg2+). MetA, MetB, and MetC are important for binding to the promoter of the Psf gene and are involved in regulating its transcription. MetA binds to the "A" site in the promoter region, MetB to the "B" site, and MetC to the "C" site. You create binding-site mutations in the A, B, and C sites and observe what happens to transcription of the Psf gene. Your results are summarized in Table below.
Which transcription regulator(s) are normally bound to the Psf promoter in the presence of Mg2+ only?

You are interested in examining the Psf gene. It is known that Psf is normally produced when cells are exposed to high levels of both calcium (Ca2+) and magnesium (Mg2+). MetA, MetB, and MetC are important for binding to the promoter of the Psf gene and are involved in regulating its transcription. MetA binds to the "A" site in the promoter region, MetB to the "B" site, and MetC to the "C" site. You create binding-sitemutations in the A, B, and C sites and observe what happens to transcription of the Psf gene. Your results are summarized in Table below.
Table 8-12 Which transcription factors are normally bound to the Psf promoter in the presence of both Mg2+ and Ca2+?

You are interested in understanding the gene regulation of Lkp1, a protein that is normally produced in liver and kidney cells in mice. Interestingly, you find that the LKP1 gene is not expressed in heart cells. You isolate the DNA upstream of the LKP1 gene, place it upstream of the gene for green fluorescent protein (GFP), and insert this entire piece of recombinant DNA into mice. You find GFP expressed in liver and kidney cells but not in heart cells, an expression pattern similar to the normal expression of the LKP1 gene. Further experiments demonstrate that there are three regions in the promoter, labeled A, B, and C in Figure below, that contribute to this expression pattern. Assume that a single and unique transcription factor binds each site such that protein X binds site A, protein Y binds site B, and protein Z binds site C) You want to determine which region is responsible for tissue-specific expression, and create mutations in the promoter to determine the function of each of these regions. In the figure below, if the site is missing, it is mutated such that it cannot bind its corresponding transcription factor.
Which of the following proteins is likely to act as a gene repressor?

You are interested in understanding the gene regulation of Lkp1, a protein that is normally produced in liver and kidney cells in mice. Interestingly, you find that the LKP1 gene is not expressed in heart cells. You isolate the DNA upstream of the LKP1 gene, place it upstream of the gene for green fluorescent protein (GFP), and insert this entire piece of recombinant DNA into mice. You find GFP expressed in liver and kidney cells but not in heart cells, an expression pattern similar to the normal expression of the LKP1 gene. Further experiments demonstrate that there are three regions in the promoter, labeled A, B, and C in Figure below, that contribute to this expression pattern. Assume that a single and unique transcription factor binds each site such that protein X binds site A, protein Y binds site B, and protein Z binds site C) You want to determine which region is responsible for tissue-specific expression, and create mutations in the promoter to determine the function of each of these regions. In the figure below, if the site is missing, it is mutated such that it cannot bind its corresponding transcription factor.
Which of the following proteins are likely to act as gene activators?

You are interested in understanding the gene regulation of Lkp1, a protein that is normally produced in liver and kidney cells in mice. Interestingly, you find that the LKP1 gene is not expressed in heart cells. You isolate the DNA upstream of the LKP1 gene, place it upstream of the gene for green fluorescent protein (GFP), and insert this entire piece of recombinant DNA into mice. You find GFP expressed in liver and kidney cells but not in heart cells, an expression pattern similar to the normal expression of the LKP1 gene. Further experiments demonstrate that there are three regions in the promoter, labeled A, B, and C in Figure below, that contribute to this expression pattern. Assume that a single and unique transcription factor binds each site such that protein X binds site A, protein Y binds site B, and protein Z binds site C) You want to determine which region is responsible for tissue-specific expression, and create mutations in the promoter to determine the function of each of these regions. In the figure below, if the site is missing, it is mutated such that it cannot bind its corresponding transcription factor.
Experiment 1 in Figure above is the positive control, demonstrating that the region of DNA upstream of the gene for GFP results in a pattern of expression that we normally find for the LKP1 gene. Experiment 2 shows what h appens when the sites for binding factors X, Y, and Z are removed) Which experiment above demonstrates that factor X alone is sufficient for expression of LPK1 in the kidney?

You are interested in understanding the gene regulation of Lkp1, a protein that is normally produced in liver and kidney cells in mice. Interestingly, you find that the LKP1 gene is not expressed in heart cells. You isolate the DNA upstream of the LKP1 gene, place it upstream of the gene for green fluorescent protein (GFP), and insert this entire piece of recombinant DNA into mice. You find GFP expressed in liver and kidney cells but not in heart cells, an expression pattern similar to the normal expression of the LKP1 gene. Further experiments demonstrate that there are three regions in the promoter, labeled A, B, and C in Figure below, that contribute to this expression pattern. Assume that a single and unique transcription factor binds each site such that protein X binds site A, protein Y binds site B, and protein Z binds site C) You want to determine which region is responsible for tissue-specific expression, and create mutations in the promoter to determine the function of each of these regions. In the figure below, if the site is missing, it is mutated such that it cannot bind its corresponding transcription factor.
In what tissue is factor Z normally present and bound to the DNA?

You are interested in the regulation of gene Q. Proteins G, H, and J are proteins that are important for regulating gene Q. and bind to its promoter region in a sequence-specific fashion. Proteins G and H both bind to site "A" but cannot bind to site "A" at the same time. Protein J binds to site "B" on the promoter. The promoter region is diagrammed in the figure below,
You develop a cell-free transcriptional system to study the effects of proteins G, H, and J on the transcription of gene Q. Using this system, you can examine the effects of adding these proteins to the transcriptional system in equal amounts and measuring how much gene Q is produced)
When you add these proteins to the system, you get the results shown in the table below.
Which proteins are likely to act as gene activators?

You are interested in the regulation of gene Q. Proteins G, H, and J are proteins that are important for regulating gene Q. and bind to its promoter region in a sequence-specific fashion. Proteins G and H both bind to site "A" but cannot bind to site "A" at the same time. Protein J binds to site "B" on the promoter. The promoter region is diagrammed in the figure below,
You develop a cell-free transcriptional system to study the effects of proteins G, H, and J on the transcription of gene Q. Using this system, you can examine the effects of adding these proteins to the transcriptional system in equal amounts and measuring how much gene Q is produced)
When you add these proteins to the system, you get the results shown in the table below.
Which proteins are likely to act as gene repressors?

You are interested in the regulation of gene Q. Proteins G, H, and J are proteins that are important for regulating gene Q. and bind to its promoter region in a sequence-specific fashion. Proteins G and H both bind to site "A" but cannot bind to site "A" at the same time. Protein J binds to site "B" on the promoter. The promoter region is diagrammed in the figure below,
You develop a cell-free transcriptional system to study the effects of proteins G, H, and J on the transcription of gene Q. Using this system, you can examine the effects of adding these proteins to the transcriptional system in equal amounts and measuring how much gene Q is produced)
When you add these proteins to the system, you get the results shown in the table below.
Your colleague looks at your data above and predicts that protein G will bind more strongly to the DNA at site A, compared to protein H. Which experiment above is critical for this prediction?

You are interested in the regulation of gene Q. Proteins G, H, and J are proteins that are important for regulating gene Q. and bind to its promoter region in a sequence-specific fashion. Proteins G and H both bind to site "A" but cannot bind to site "A" at the same time. Protein J binds to site "B" on the promoter. The promoter region is diagrammed in the figure below,
You develop a cell-free transcriptional system to study the effects of proteins G, H, and J on the transcription of gene Q. Using this system, you can examine the effects of adding these proteins to the transcriptional system in equal amounts and measuring how much gene Q is produced)
When you add these proteins to the system, you get the results shown in the table below.
Which proteins do you predict are bound to the promoter in experiment #8?

You are interested in studying the transcriptional regulation of the Gip1 promoter. The Gip1 promoter contains a binding site for the Jk8 protein that overlaps with the binding site for the Pa5 protein. Jk8 and Pa5 cannot bind DNA at the same time, but both proteins are present at high levels in adult liver cells. The binding sites for Jk8 and Pa5 are shown in Figure below.
Jk8 binds to site A while Pa5 binds to site B) You create mutations that remove the nonoverlapping sequences of either binding site A or B, and examine Gip1 mRNA production in adult liver cells that contain these mutations. The data you obtain from these experiments are shown in Table below.
You know that Gip1 is only expressed in adult liver cells and not in the liver of embryos. You also know that Jk8 and Pa5 behave similarly on ther promoters in the embryo or in the adult, in terms of whether they act as repressors or gene activators. Given the data, use of which of the following mechanisms would make the most sense for regulating the Jk8 and Pa5 proteins:

How are most eukaryotic transcription regulators able to affect transcription when their binding sites are far from the promoter?

Which of the following statements about nucleosomes is TRUE?

The expression of the BRF1 gene in mice is normally quite low, but mutations in a gene called BRF2 lead to increased expression of BRF1. You have a hunch that nucleosomes are involved in the regulation of BRF1 expression and so you investigate the position of nucleosomes over the TATA box of BRF1 in normal mice and in mice that lack either the BRF2 protein (BRF2-) or part of histone H4 (HHF-) (histone H4 is encoded by the HHF gene). The Table below summarizes your results. A normal functional gene is indicated by a plus sign (+).
Which of the following conclusions CANNOT be drawn from your data?

Enhancers can act over long stretches of DNA, but are specific about which genes they affect. How do eukaryotic cells prevent these transcription regulators from looping in the wrong direction and inappropriately turning on the transcription of a neighboring gene?

Combinatorial control of gene expression

In principle, how many different cell types can an organism having four different types of transcription regulators and thousands of genes create?

You are studying a set of mouse genes whose expression increases when cells are exposed to the hormone cortisol, and you believe that the same cortisol-responsive transcriptional activator regulates all of these genes. If your hypothesis is correct, which of the following statements below should be TRUE?

Which of the following statements about how fruit flies can develop an eye in the middle of a leg is TRUE?

Which of the following statements about iPS cells is FALSE?

The MyoD transcriptional regulator is normally found in differentiating muscle cells and participates in the transcription of genes that produce muscle-specific proteins, such as those needed in contractile tissue. Amazingly, expression of MyoD in fibroblasts causes these cells derived from skin connective tissue to produce proteins normally only seen in muscles. However, some other cell types do not transcribe muscle-specific genes when MyoD is expressed in them. Which of the following statements below is the best explanation of why MyoD can cause fibroblasts to express muscle specific genes?

In mammals, individuals with two X chromosomes are female, and individuals with an X and a Y chromosome are male. It had long been known that a gene located on the Y chromosome was sufficient to induce the gonads to form testes, which is the main male-determining factor in development, and researchers sought the product of this gene, the so-called testes-determining factor (TDF). For several years, the TDF was incorrectly thought to be a zinc finger protein encoded by a gene called BoY. Which of the following observations would most strongly suggest that BoY might NOT be the TDF?

Which of the following is NOT a general mechanism that cells use to maintain stable patterns of gene expression as cells divide?

Which of the following statements about DNA methylation in eukaryotes is FALSE?

Which of the following examples does NOT describe a mechanism of post-transcriptional control of gene expression?

Using genetic engineering techniques, you remove the sequences that code for the ribosome-binding sequences of the bacterial LacZ gene. The removal of these sequences will lead to

miRNAs, tRNAs, and rRNAs all

Which of the following is NOT involved in post-transcriptional control?

MicroRNAs

Which of the following statements about miRNAs is FALSE?

Which of the following statements about RNAi is TRUE?

The owners of a local bakery ask for your help in improving a special yeast strain they use to make bread) They would like you to help them design experiments using RNA interference to turn off genes, to allow them to test their hypothesis that certain genes are important for the good flavors found in their bread) Of the components in the following list, which is the most important to check for in this yeast strain if you would like this project to succeed?

The long noncoding RNA Xist