Epigenetics and Mutations Flashcards
(22 cards)
Which nucleotides are methylated
Name the nucleotide derivative whose deficiency would affect methylation
S-adenoylmethionine(SAM)
WHat enzyme catalyzes methylation of DNA
De Novo methyl Transferases (DNMTs)
What is the function of Piwi-interacting RNA(piRNA))
Involved in silencing transposable elemens in the DNA and improve genomic stability
What is the name of regions of chromatin which are not expressed
Heterochromatin region
How does methylation affect gene expression
Repress Gene expression
At what position is Cytosine methylated
At position 5
Which Cytosines are susceptible to methylation
Cytosine in a āCGā Sequence
How does methylation cause gene repression
Causes tight wrapping of DNA around histones
What is the name given to Regions of chromosomes with tightly bound DNA tohistones
Heterochromatic Regions
On the cytogenetic scale what indicates heterochromatic regions
Bright white dots
What is Euchromatin
Acetylated regions of Histones, that are likely to be transcribed
What type of histone methylation is in Euchromatin
H3-K4 methylation
What type of histone methylation is in Heterochromatin
H3-K9 methylation
Which protein is used for the deacetylaion of histone tails and give an example
Histone deactylases, an example is RPD3
Which protein is used for the acetylaion of histone tails and give an example
Histone acetyltransferases
What is uniparental disomy
When both pairs of chromosomes is gotten from one parent
Name the types of uniparental disomy
Isodisomy and heterodisomy
How does uniparental disomy usually occur
When the cell tries to return the chromosome number back to 2 after trisomy mutation occurs
What is anglemans syndrome
It is a paternal uniparental disomy for chromosome 15
What is the Prader-willi Syndrome
It is a maternal uniparental disomy for chromosome 15
