Exam 15: Regulation of Gene Expression in Eukaryotes

In the GAL gene system, ________ are cis-acting regulatory elements, and ________ protein is a trans-acting regulatory protein.

If a mouse inherits a deletion in the SHH enhancer, what effect would you expect to see?

In yeast, if you want to prevent the Gal4 regulatory protein from binding near each of the GAL genes, which sequence element would you target?

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

Histone deacetylase (HDAC)inhibitors are commonly used as mood stabilizers or in the treatment of neurodegenerative diseases. What effect would a HDAC inhibitor have on the target cells?

Gal4 is mutated such that it still binds to the DNA but cannot interact with Gal80. What effect would you expect to see in the absence of galactose?

Both cis-acting sequences and trans-acting proteins affect gene expression in eukaryotic chromosomes. What are the three basic mechanisms by which trans-acting proteins access specific regulatory DNA sequences in eukaryotic chromosomes? Describe how chromatin is altered in each of these processes.

Demethylation and acetylation lead to open chromatin structure and are associated with ________ regions of genomes.

For the following gene, which mutant likely has lost its enhancer? Mutant # Deletion Region % Transcription WT None 100% 1 1-200 150% 2 250-400 100% 3 500-800 50% 4 950-1100 0%

Chromatin remodeling involves both sliding and relocating of the nucleosomes. Which eukaryotic chromatin remodeling complex is likely involved?

In animals, the ________ enzyme cuts pri-miRNA to produce miRNA.

In the GAL gene system, which protein acts as an activator protein through its transcription-initiating effect?

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 __________.

What are the protein-binding sequences that direct enhancers to interact with the intended promoter and that block communication between enhancers and other promoters?

What effect does methylation of CpG islands have on human promoters?

Which enzyme cuts dsRNA into 21-25 bp fragments during RNAi?

Typically, methylation of nucleosome N-terminal tails leads to __________.

In gal+ yeast, what is the product of the galactose utilization pathway?

Which sequences would likely have both a nucleosome-depleted region (NDR)and a poly A/T tract to attract transcriptional activators to a transcription start sequence?

Which of the four nucleotides are typically methylated in "islands," resulting in closed chromatin structure?