Epigenetics

Question 1

DNA is packaged into higher order structures called…

Answer 1

• Nucleosome - DNA wraps around histone beads
• Chromatin - Nucleosome and structural complex composing DNA

Question 2

Differentiate Acetylation and Methylation

Answer 2

Acetylation - Addition of acetyl group to histone tail allows for easier reading of DNA, promoting gene expression

Methylation - Addition of methyl group to cytosine of DNA suppresses gene expression. Done by Methyl Transferases (DNMTs)

Question 3

What is the purpose of chromatin remodeling?

Answer 3

Crucial for turning genes on or off without affecting the DNA itself. This is done using various remodeling complexes

Question 4

What are the forms of chromatin remodeling?

Answer 4

• Nucelosome Sliding
• Nucelosome Ejecting
• Histone Exchange

Question 5

What is used to remodel chromatin?

Answer 5

Multi-protein complexes that require ATP to work. Any domains present will decide how they remodel.

Question 6

What is ARID1A?

Answer 6

A gene that encodes for the SWI/SNF chromatin remodeling structure. Regulates DNA transcription.

Otherwise known as a tumour suppressor gene. The loss of function will cause disrupted chromatin remodelling and uncontrolled gene expression.