Quiz 4/20 Flashcards
In mammals, what percentage of the cytosine is methylated?
2-7%
What does DNA methylation do to gene expression?
It usually silences it
Barr body is highly ____________
methylated
In DNA methylation, how is the protein prevented from binding?
A methyl group is in the major groove and hinders protein binding
Which two enzymes are affected by methylation?
- HpaII
- MspI
Describe the DNA methylation process
- Forms 5’- methylcytosine
- hemimethylated or fully methylated
CpG islands are located where?
Near the promoter region
Methylation of CpG islands is closely related to what process?
gene expression
What are housekeeping genes?
CpG islands that are unmethylated
What are tissue-specific genes?
CpG islands that are only methylated when not expressed
The binding of the activator is prevented how?
Methylation of CpG islands
Methylated CpG islands recruit which proteins that compact DNA?
methyl-CpG-binding proteins
Methylated DNA sequences are inherited during ___________________.
Cell division
De novo methylation or demethylation is rarely observed and a highly regulated way to control specific ___________________ during development or _____________________________.
gene expression, tissue-specific gene expression.
Newly-made DNA is
A. Not methylated
B. Methylated
B. Methylated
Double-stranded DNA is what type of methylated?
hemimethylated
Double-stranded DNA is also FULLY methylated