Chapter 15- Euk. Gene Regulation
steps at which gene regulation can occur
- Posttranslational modification - Translation - RNA processing - Transcription
What DNA sequence is methylated? 5'-CA-3' 5'-CG-3' 5'-GC-3' 5'-AC-3
5'-CG-3'
DNA methyltransferase is an enzyme that attaches a methyl group to the ____ position of the ____ base.
5; cytosine
What is the name for stretches of DNA of 1000-2000 bp in length containing a high number of CpG sites that are found near gene promoters?
CpG islands
Which enzyme catalyzes the formation of 5-methylcytosine?
DNA methyltransferase
In order to inhibit transcription, a methyl-CpG-binding protein would bind to a methylated CpG island and recruit which of the following enzymes to modify the histones in the region?
Histone deacetylase
General transcription factors are required for the binding of____ ___ to the core promoter and its progression to the elongation stage.
RNA polymerase
represents de novo methylation?
The methylation of DNA that was previously unmethylated
Select the organism with the highest amount of DNA methylation. Drosophila Vertebrates Yeast
Vertebrates
DNA methylation is __ attachment of methyl groups to DNA
covalent
When a methyl-CpG-binding protein associates with a methylated CpG island, it recruits an enzyme called histone___ to modify histone proteins which makes it more difficult to remove nucleosomes from the DNA.
deacetylase
Methylation of the cytosine in both strands is called __ methylation, and methylation of only one strand is called ____ methylation
full; hemi
Gene regulation means that
gene expression can be controlled so that genes can be expressed at high or low levels
Human nerve cells and muscle cells look quite different from each other due to differences in
gene regulation
Genes that code for proteins that are required in most cells of a multicellular organism are called _____.
housekeeping genes
CpG islands near the promoters of tissue-specific genes are often
methylated
The ability of humans to develop tans to protect their skin cells from UV rays by inducing genes that provide protection against UV radiation is an example of gene
regulation
Genes that are highly regulated and may be expressed only in certain cell types are called
tissue-specific genes
A protein that influences the ability of RNA polymerase to transcribe a given gene is termed a(n)
transcription factor
The methylation state of DNA is inherited during cell division.
true
The cytosines in CpG islands near housekeeping genes are
unmethylated