Vertebrate genomic DNA base modifications and their detection

Question 1

What are the two most widely occuring DNA base modifications?

Answer 1

2-methyladenosine and 5-methylcytosine

Question 2

What kind of enzyme catalyses the formation of 5-methylcytosine?

Answer 2

DNA methyl transferase (DMNT)

Question 3

What molecule donates the methyl group for the formation of 5-methylcytosine?

Answer 3

S adenosyl methionine

Question 4

What occurs as a result of DNA methylation?

Answer 4

TFs bind less regularly to the DNA

Question 5

What can methylation do to a chromosome?

Answer 5

cause it to condense

Question 6

Is 5HMC heritable?

Answer 6

Yes

Question 7

Why is 5HMC heritable?

Answer 7

At CG dinucleotides the C is methylated on both strands, and after DNA rep the DNMT1 enzyme wil methylate the C on the new strand

Question 8

which protein recognises hemi-methylated DNA?

Answer 8

NP95

Question 9

Which protein catalyses new methylation of DNA?

Answer 9

DNMT3A AND DNMT3B

Question 10

Which enzymes can wipe DNA methylation?

Answer 10

TET

Question 11

What method can be used to see how much cytosine methylation is in the DNA?

Answer 11

Bisulphite sequencing