Exam 13: Regulation of Gene Expression in Bacteria and Bacteriophage

Molecular biologists can determine experimentally whether a region of DNA contains closed chromatin or open chromatin by assessing the sensitivity of the region to__________ .

Trans- acting regulators of gene expression include?

Enhancers and silencers are?

__________in Drosophila results from the movement of the transcriptionally active w+ allele into the centromeric heterochromatin region of the fruit- fly X chromosome.

Chromatin from two tissues, skin and liver, was extracted and analyzed near the gene Twist. The liver chromatin was found to be more DNAse sensitive than the chromatin from skin cells. What might explain this difference?

Prader- Willi syndrome is a genetic disorder involving a partial deletion of chromosome 15q on the paternal chromosome. When both copies of a gene (or chromosome) are functional but only one is expressed, this is an example of __________ .

In the GAL gene system, which protein binds to the activation domain of the activator protein, ultimately blocking transcription in the absence of galactose?

If you block histone deacetylase, what effect would you expect to see on transcriptional activity?

Typically, acetylation of histone tails leads to____________ .

During RNAi, what do miRNAs target for destruction?

Eukaryotes use these highly specialized enhancer elements, which regulate the transcription of multiple genes packaged in complexes of closely related genes (e.g., fi- globin).

What role do chromatin remodelers play in eukaryotic gene expression?

Multicellular organisms generally utilize more complex gene regulation than unicellular organisms via mechanisms that include?

The gene encoding coat color is X- linked, and male cats have a single copy of the X chromosome. They can therefore express either the O or o allele, resulting in orange or black coat, respectively. Female cats, on the other hand, have two copies of the X chromosome. Thus, they can be heterozygous and express either orange or black pattern called tortoiseshell. Using this information, list the possible genotypes for these individuals: • orange male • orange female • black male • black female • tortoiseshell

Loss of Xist gene due to mutation leads to defects in which epigenetic process?

Which protein complex binds dsRNA fragments to generate ssRNAs for RNAi?

Gene regulation in eukaryotes often involves which of the following, which are not also used by prokaryotes?

What are the three mechanisms by which chromatin remodelers can move nucleosomes?

Viruses with dsRNA genomes evolved a long time ago and can be found in parasitic relationships with species from a variety of taxa. What mechanism do eukaryotes use to combat such viruses?

When CpG islands are unmethylated,_________ .