Molecular Biology Module 5: Gene Regulation

You transfer wildtype E.coli from plates containing lactose to plates containing both glucose and lactose. Under these conditions indicate what sequence of events will occur at the lac operon promoter.

1

In the context of prokaryotic gene regulation, an operator is the:

1

TBP, the TATA Binding Protein:

1

(USMLoid) The VHL gene is often mutated in people suffering from von Hippel-Lindau (VHL) disease. The VHL protein is found in a ubiquitin-ligase complex that targets the transcription factor Hypoxia Inducible Factor 1 (HIF-1). In VHL patients HIF-1 is not targeted for destruction by the ubiquitination pathway. Which of the following genes will most likely show increased gene expression as a result?

1

שאלה #57577

		1. Endostatin receptor
		2. Insulin
		3. Thyroid hormone receptor
		4. Vascular Endothelial Growth Factor Receptor
		5. Insulin receptor

The key to answering this question is not to remember the pathways, but simply to build the sensible association between hypoxia and a need for more blood vessels. That leads you directly to the VEGF receptor. That simple.

מיין לפי

(USMLoid) A researcher has identified a gene of unknown function by linkage analysis in an extended family showing early onset Alzheimer dementia. While characterising the regulation of this gene in a transgenic cell-culture system the researcher has focussed on a 860 bp sequence located 2,412 bp before the start of transcription. When it is removed, expression of the gene decreases 30-fold. When it is put back in either orientation, the expression is restored. Which of the following best defines this sequence?

1

שאלה #57578

		1. 5' untranslated region
		2. Enhancer
		3. General transcription factor binding site
		4. Promoter
		5. TATA Box

מיין לפי

(USMLoid) Sequencing the factor IX gene of a 12-year old hemophilia patient shows a T->G point mutation 20 base-pairs before the first exon of the gene. This is most likely to disrupt the binding of which of the following?

1

שאלה #57579

		1. The mRNA 5'-CAP binding protein.
		2. DNA polymerase
		3. Transcription factor
		4. Histone
		5. snRNP

מיין לפי

(USMLoid) Transcription in eukaryotes is often regulated by promoter sequence and enhancer elements. Which of the following best describes enhancers?

1

שאלה #57580

		1. Nascent mRNAs that bind to promoters.
		2. Zinc-finger family transcription factors that bind the TATA box
		3. DNA sequences that bind histones
		4. Short DNA sequences located before or after the promoter.
		5. Nuclear hormone receptors that bind to DNA

מיין לפי

What is the homeodomain?

1

שאלה #57581

		1. is a transmembrane protein domain.
		2. encodes the homeobox.
		3. encodes a transcription factor.
		4. binds specific DNA sequences.
		5. contains the serine protease active site.

מיין לפי

5. contains the serine protease active site.

1

שאלה #57582

		1. premature release of ribosomes from the RNA
		2. Activation of the trp repressor protein
		3. Elimination of the Ribosome Binding Site
		4. a reading frame shift
		5. Prevention of RNA synthesis

מיין לפי

here are the regulatory regions of genes encoding Y and ΔY (top). You have cells which express the steroid hormone (X) receptor (Xrec) under the control of a constitutive promoter. Hormone-bound Xrec is a transcription activator binding to its recognition sequence XrecBS. The transcription factor Y contains a DNA-binding domain at the amino terminus that recognizes the sequence YBS and a c-terminus polyglutamine sequence. The transcription factor ΔY is the same as Y, but is missing the c-terminus polyglutamine sequence. The relative half-lives of X, Y, and ΔY are as follows t½X = 5, t½Y = 5, t½ΔY = 15. Which of the graphs best describes the rate of transcription from the Y promoter after the addition of hormone X at the time indicated? Select one:

1

מיין לפי

		1. A2 → B2 → C2
		2. A1 → B3 → C1
		3. A1 → B2 → C2
		4. A2 → B1 → C1
		5. A1 → B4 → CI
		6. A2 → B4 → C1
		7. A1 → B4 → C2
		8. A2 → B2 → C1

		1. DNA sequence which binds the repressor.
		2. DNA sequence which binds the RNA polymerase.
		3. DNA sequence where transcription of the operon begins.
		4. part of the operon encoding the repressor.
		5. protein which regulates transcription from the promoter.

		1. is sometimes needed for the initiation of transcription in prokaryotes
		2. binds to the sequence TATA of prokaryotic promoters
		3. is part of the prokaryotic RNA polymerase holoenzyme
		4. is never needed for the initiation of transcription in eukaryotes
		5. is always needed for the initiation of translation in eukaryotes
		6. binds to the prokaryotic ribosome binding site (RBS)
		7. binds to the Kozak sequence
		8. is part of a eukaryotic transcription initiation complex

Molecular Biology Module 5: Gene Regulation

Discuss, Learn and be Happy דיון בשאלות

You transfer wildtype E.coli from plates containing lactose to plates containing both glucose and lactose. Under these conditions indicate what sequence of events will occur at the lac operon promoter.

שאלה #57574

In the context of prokaryotic gene regulation, an operator is the:

שאלה #57575

TBP, the TATA Binding Protein:

שאלה #57576

שאלה #57577

שאלה #57578

(USMLoid) Sequencing the factor IX gene of a 12-year old hemophilia patient shows a T->G point mutation 20 base-pairs before the first exon of the gene. This is most likely to disrupt the binding of which of the following?

שאלה #57579

(USMLoid) Transcription in eukaryotes is often regulated by promoter sequence and enhancer elements. Which of the following best describes enhancers?

שאלה #57580

What is the homeodomain?

שאלה #57581

5. contains the serine protease active site.

שאלה #57582

שאלה #57583

Molecular Biology Module 5: Gene Regulation

Discuss, Learn and be Happy דיון בשאלות

You transfer wildtype E.coli from plates containing lactose to plates containing both glucose and lactose. Under these conditions indicate what sequence of events will occur at the lac operon promoter.

In the context of prokaryotic gene regulation, an operator is the:

TBP, the TATA Binding Protein:

(USMLoid) Sequencing the factor IX gene of a 12-year old hemophilia patient shows a T->G point mutation 20 base-pairs before the first exon of the gene. This is most likely to disrupt the binding of which of the following?

(USMLoid) Transcription in eukaryotes is often regulated by promoter sequence and enhancer elements. Which of the following best describes enhancers?

What is the homeodomain?

5. contains the serine protease active site.

בקשה לשינוי התשובה / תיקון שאלה gavel

בקשה למחיקת השאלהmood_bad

בקשה לשינוי התשובה / תיקון שאלה

בקשה למחיקת השאלה