Flashcards in Intro to Epigenetics Deck (43):
A change in phenotype that is caused by non-DNA sequence changes inherited through mitosis.
- Identical sequences.
What three components of epigenetic mechanisms?
- Histone tail modifications.
- DNA cytosine methylation.
- Non-coding RNAs.
When can you modify histone tails?
What is the result of DNA methylation (5meC)?
Adenine methylation is involved in..?
What are three types of non-coding RNAs involved in epigenetic modifcations?
How much of RNA will give rise to a protein?
0.1%, (99% won't give rise to protein).
RNA regulation involves?
What experiment won the nobel prize in 2006, in relation to the RNA world?
What other experiments contributed to the field of RNA?
Describe the miRNA and siRNA silencing pathways.
Draw the diagram.
What are the two outcomes of miRNA and siRNA silencing pathways?
- mRNA cleavage and translation repression.
Where are miRNA genes often located?
What is heterochromatic silencing?
- Silencing of tightly packed DNA.
- Down-regulation to prevent insertion into lncRNAs?
How much of the genome is transposons and retrotransposons?
Describe the process of transacting siRNA silencing?
What is the difference between the one hit and two hit pathways?
What is the role of TAS3 in tasiRNAs?
What is the effect of the rdr6 mutation leading to no production of tasiRNAs in ARF3 and ARF4?
Describe the process of miRNA processing.
What are the functional domains of the Argonaute protein? Draw.
How was the Ago structure determined?
PIWI is the ______ domain.
What are the small RNA classes in plants, their precursors and quantity?
What are the RNA silencing components, their function and organism?
What are the roles of silencing in nature?
What are some targets of some conserved miRNAs and their functions?
What is an example of RNA viruses being targeted by RNA silencing?
What is the function of PAZ domain in the Ago protein?
How is adaptive immunity passed through the plant?
What happens if transposon activity is not controlled (silenced)?
What are the methods for silencing transposon activity?
DNA methylation, histone modification and siRNA production.
How much of our genome is derived from transposons?
Where are heterochromatic siRNAs preferentially derived from? Why?
Pericentromeric regions and centromeric regions.
Density of sRNA-homologous loci is highest in centromeric and pericentromeric regions, which contain lots of repeat sequences like transposons.
siRNA direct transcriptional silencing.
In terms of chromatin regulation, how can you turn a gene off?
Describe the structure of histones.
Describe the histone code hypothesis.
Summarise the RdDM Pathway.
(RNA derived DNA methylation).
Methylated transposable elements can silence their flanking gene.
True or False?
What is the effect of reduced cytosine methylation in transposable elements?
What is the effect of transposons jumping next to genes?