Molecular Biology Module 5: Gene Regulation

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:

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Acetylation of histones often results in:

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The TAF1 subunit of TFIID is a histone acetylase. Which of the following is the most likely consequence?

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Neurons, after they are first born, slowly start to express a neurofilament gene (NF-L) for the first time. The promoter of the NF-L gene is rich in CpG sequences. Which of the following would you expect to observe in the NF-L promoter as the gene becomes increasingly active in neurons?

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Which of the following is directed by transcription activators in eukaryotic cells such as to make DNA more accessible for the transcription machinery.

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(USMLoid) DNA methylation-induced repression of the Dapk (Death associated protein kinase) gene has been observed in 80% of colorectal carcinomas. Increased methylation of the Dapk gene most likely occurs at which of the following?

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Embryonic development and cell differentiation are largely driven by gene regulation. The most common mechanism is at which of the following levels?

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The four labelled DNA sequences are bound by proteins with sequence specific DNA-binding domains. Which one most likely binds to a PolII general transcription factor?

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(USMLoid) The protein encoded the gene ZEB1 was discovered to induce genes causing an Epithelial Mesenchymal Transition (EMT) during breast cancer tumor progression. The gene sequence and protein X-ray crystallography data showed that ZEB1 encodes a Zinc-finger motif. Which of the following is a most likely characteristic of the ZEB1 protein.

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In the context of prokaryotic gene regulation, a repressor is:

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Molecular Biology Module 5: Gene Regulation

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Acetylation of histones often results in:

The TAF1 subunit of TFIID is a histone acetylase. Which of the following is the most likely consequence?

Neurons, after they are first born, slowly start to express a neurofilament gene (NF-L) for the first time. The promoter of the NF-L gene is rich in CpG sequences. Which of the following would you expect to observe in the NF-L promoter as the gene becomes increasingly active in neurons?

Which of the following is directed by transcription activators in eukaryotic cells such as to make DNA more accessible for the transcription machinery.

(USMLoid) DNA methylation-induced repression of the Dapk (Death associated protein kinase) gene has been observed in 80% of colorectal carcinomas. Increased methylation of the Dapk gene most likely occurs at which of the following?

Embryonic development and cell differentiation are largely driven by gene regulation. The most common mechanism is at which of the following levels?

The four labelled DNA sequences are bound by proteins with sequence specific DNA-binding domains. Which one most likely binds to a PolII general transcription factor?

In the context of prokaryotic gene regulation, a repressor is: