Exam 16: Regulation of Gene Expression

With respect to bacteria, the term "lysogeny" refers to

What is the difference between a prophage and a provirus, based on what you know about HIV and bacteriophage ?

Imagine that the promoter for gene X becomes highly methylated.How will this affect the expression of gene X?

By adding ubiquitin to p53, HPV is affecting gene expression at the level of

A loss-of-function mutation occurs in one of the late genes in a lytic bacteriophage.Which change is least likely?

Which gene would most likely be under inducible expression control?

You are tasked with mapping the position of chromatin modifications within the genome of a eukaryotic chromosome.Where would you most likely encounter regions of high DNA methylation?

Reduction of tat in HIV would lead to a(n) (reduction/increase) _______ in transcription elongation.

Imagine that gene X is in a chromosome region where the histones are highly acetylated.How will this affect its expression?

The virus that causes chicken pox can also cause shingles later in life.This is because the virus enters into a _______ phase.

Working in the laboratory, you infect host cells with a virus that is known to have both lytic and lysogenic life phases.Which result would definitively confirm that the virus has indeed entered a lysogenic phase?

-galactoside transacetylase is

An operon that would be controlled by both presence of lactose and low levels of glucose would need two control mechanisms: first, a(n) _______ system to turn on genes to use lactose when it is present, and then a positive regulation system to only turn on lactose metabolism genes in the absence of glucose.

Co-repressors are usually present in _______ systems, which tend to be found in _______ pathways.

A "riboswitch" is an mRNA that alters production of protein by binding a small molecule.A riboswitch is most likely involved in regulation at the _______ level.

If the gene encoding the trp repressor is mutated such that the repressor can no longer bind tryptophan but can still bind the operon, will transcription of the trp operon occur?

Refer to the figure showing the potential points for the regulation of gene expression. Blocking which point would be considered transcriptional control?

Ubiquitin forms a complex with proteins and then binds with _______, forming a sort of "molecular chamber of doom" where proteins are digested into small peptides and amino acids.

When E.coli is grown in a medium with low levels of lactose,

In bacterial cells, the concentration of cAMP is _______ correlated with the concentration of glucose; hence, glucose concentrations should _______ correlated with the amount of transcription in the lac operon (assuming that lactose is abundant).