BIOL 4003 module 8 quiz

A small effector molecule induces transcription. Which combination below is consistent with this idea?

Repressor and inducer

Activator and inhibitor

Repressor and corepressor

None of the above

Repressor and inducer

With regard to lac operon regulation via catabolite activator protein (CAP), which of the following statements is correct?

Glucose lowers cAMP levels. CAP binds to the DNA when cAMP is bound to CAP.

Glucose lowers cAMP levels. CAP does not bind to the DNA when cAMP is bound to CAP.

Glucose raises cAMP levels. CAP binds to the DNA when cAMP is bound to CAP.

Glucose raises cAMP levels. CAP does not bind to the DNA when cAMP is bound to CAP.

Glucose lowers cAMP levels. CAP binds to the DNA when cAMP is bound to CAP.

Let's suppose you have isolated a mutant strain of E. coli in which the lac operon is constitutively expressed. You create a merozygote in which the mutant strain also contains an F' factor with a normal lac operon and a normal lacI gene. You then compare the mutant strain and the merozygote with regard to their β-galactosidase activities in the presence and absence of lactose. You obtain the following results:

Strain Addition of lactose (no glucose) Amount β-Galactosidase

Normal Yes 100

Mutant No 100

Mutant Yes 100

Merozygote No 100

Merozygote Yes 200

Which of the following is consistent with these data?

The mutation is in the lacI gene and results in a lac repressor that cannot bind to the operator

The mutation is in the lac operator and prevents the lac repressor from binding to the operator

The mutation is in the lacI gene and results in a lac repressor that cannot bind allolactose

All of the above

The mutation is in the lac operator and prevents the lac repressor from binding to the operator

For a riboswitch that controls transcription, what is the effect of a regulatory molecule such as TPP?

It binds to a repressor and causes the repressor to bind to an operator site.

It binds to an activator and causes the activator to bind to an operator site.

It binds to an RNA molecule and causes a change in its conformation.

It binds directly to the promoter and prevents transcription.

It binds to an RNA molecule and causes a change in its conformation.

Let's suppose that mediator has interacted with an activator protein. What would you expect to happen next?

TFIID would bind to the core promoter.

RNA polymerase would bind to the core promoter.

Histones would be displaced from the core promoter.

RNA polymerase would switch to the elongation phase of transcription.

RNA polymerase would switch to the elongation phase of transcription.

With regard to eukaryotic gene transcription, histones are not removed during

the formation of the preinitiation complex.

transcriptional elongation.

phosphorylation of CTD.

the formation of nucleosome-free regions.

phosphorylation of CTD.

The following list describes events that are required for transcription of a eukaryotic gene. Put them in the correct order.

Elongation

Binding of activators

Chromatin remodeling and histone modification

Formation of the pre-initiation complex

2, 3, 4, 1

1, 4, 2, 3

4, 3, 2, 1

2, 1, 4, 3

2, 3, 4, 1

During the phenomenon of proximal promoter pausing,

the CTD (carboxyl terminal domain) of RNA polymerase gets phoshorylated.

RNA polymerase stops transcribing the DNA due to the binding of NELF (negative elongation factor) and DSIF (DRB-sensitivity-inducing factor).

TFIIH converts the preinitiation complex into an open complex.

TFIIB, TFIIE, TFIIH, and mediator are released from RNA polymerase.

RNA polymerase stops transcribing the DNA due to the binding of NELF (negative elongation factor) and DSIF (DRB-sensitivity-inducing factor).

Which of the following event(s) need to happen for the glucocorticoid receptor to activate a gene?

Protein-protein interaction (e.g., dimer formation)

The binding of the glucocorticoid receptor to a GRE

The binding of a small effector molecule to the glucocorticoid receptor subunits

all of the above happen

all of the above happen

Which of the following phenomena could you study using ChIp-Seq?

To see if a regulatory transcription factor binds to mediator and/or TFIID

To measure the level of transcription of a given gene in real time.

To analyze the binding of protein(s) to DNA on genome-wide scale.

To determine if a mutation at a regulatory site alters the transcription level of a given gene.

To analyze the binding of protein(s) to DNA on genome-wide scale.