epigenetic control of gene expression

Question 1

epigenetic control

Answer 1

gene switched on or off
attachment and removal of chemical groups (epigenetic markers) to or from DNA or histone proteins
dont alter base sequence
alter how easy it is fro enzymes and other proteins for transcription to interact and transcribe DNA
play role in normal cellular process and occur in response to changes in environment

Question 2

epigenetic changes and inheritance

Answer 2

most epigenetic marks on DNA removed between generations.
some escape removal process and passed to offspring
expression of some
expression of genes in offspring can be affected by environmental changes that affected parents/grandparents

Question 3

methylation

Answer 3

increased mehylation switches gene off
attaches to DNA coding for gene
changes DNA structure so transcriptional machinery cant interact with gene so its not expressed

Question 4

acetylation

Answer 4

decreased acetlyation of histone switches gene off
histones acetylated - chromatin less condensed transcriptional machinery can access DNA allowing it to b transcribed
acetyl groups removed - chromatin highly condensed - genes cant be transcribed - transcriptional machinery cant physically access them
Histone deacetylase HDAC enzyme responsible for removing acetyl groups

Question 5

drugs

Answer 5

epigenetic chages reversible
drugs designed to counteract epigentic changes that cause disease
increased methylation -> drugs that stop DNA methylation
decreased acetylation -> HDAC inhibitor drugs
however need to make sure as specific as possible