Download Epigenetics Questions Jessica Lewis C Block How does methylation

Epigenetics Questions
Jessica Lewis
C Block
1.
How does methylation and acetylation affect transcription? What
part of the genome is modified?
Methylation and acetylation affect transcription by the different
enzymes, in this case a methyl group or an acetyl group, attaches to a
histone, which add or take away tags from the chromatin. These tags are
then read by other proteins, telling the chromatin to either condense or
loosen so that other proteins can either repress or further activate
transcription.
2.
What is the literal definition of “epigenetic”? Formulate a more
comprehensive, working definition based on this article.
Epigenetic literally means above, or in addition to genetics. In more
comprehensive terms, epigenetics is the study of gene expression,
referring specifically to factors that are not controlled by the DNA
sequence; generally this means outside factors or other conditions that
can affect gene expression without changing the content of the DNA.
3. How does cocaine affect epigenetic control of gene expression?
Cocaine affects epigenetic control of gene expression by unwinding
histones, this changes means that genes are more susceptible to being
expressed, because the genes are not as tightly coiled and inaccessible
as before. If an animal receives cocaine chronically it can make many
different genes in the brain’s reward center. Cocaine turns on many
more genes than are normally on, resulting in desensitized genes in
some cases, while in other cases, the genes become overactive for
extended periods of time. Cocaine’s loosening of histones, sets all of
these results into motion.
4.
What was the evidence in mice that epigenetic modification could
last throughout a lifetime and even in multiple generations?
Evidence of epigenetic modification lasting throughout a lifetime first
has evidence in the study of depressed mice. After being exposed to
social situations that would further induce depression, the mice,
particularly with mice of a gentle nature, should strong signs of
depression. It seems that through methylation many genes in the
mice’s brain were affected so that the mice could not feel good. While
antidepressants did help, it is still true that many of the genes were
altered chronically or permanently. Epigenetic modification is also
shown to last through multiple generations in the case of the mice’s
maternal actions towards their offspring, and the resulting maternal
actions of those offspring. A receptor in genes receives hormones that
then affect the methyl groups in the genes of the offspring based on
their anxious, fearful feelings (or lack thereof). This is exemplified with
mother who is easy-going and attentive causes methyl groups to be
removed in the children, so that they are also easy-going, attentive
mothers as a response to how the mother nurtured her pups. The
mother who was more hostile and inattentive, had children that were
also hostile and inattentive because methyl groups were evident on
genes, due to how the mother raised her pups.
5. After reading the article and exploring the website, what is your
impression of epigenomics? Support your opinion with at least two
more examples you discovered on the website. Where do you think we
may feel the most impact from research in this field?
After exploring the website, I am believe that epigenetics have a very
large role in gene expression. I think it’s very important that we try to
control the factors that are within our reach, so that we can prevent the
unfavorable effects of epigenetics. I gathered this by doing the
interactive rat experiment, that lets you act as the mother rate, and see
how nurturing the mouse pup, really affects how tightly wound the
chromatin is. I also believe this even after reading about epigenetics and
inheritance. Even though part of it states the difficulty of proving
inheritance due to the other possibilities such as ruling out the
possibility of genetic changes. However after reading the part of the
section that gives the example of how what a grandfather eats when he
is in his slow growth period, in some studied cases, has shown that this
will affect his sperm because this effects the how his epigenome is
replicated, which then affects future generations. Studies like this, and
studies in rats and other organisms, provide reasonable background for
the possibility of epigenetics. While it is very difficult to be certain of
epigenetics, I still think it is important to continue studies so that we can
learn more about epigenetics and then use that information to our
advantage. I think we would feel the most impact in the area of
psychological disorders, such as depression and schizophrenia. By
studying epigenetics, it is possible to see where the genes experience
damage, and how this results in affected gene expression in the brain.
By identifying these factors of gene expression, medication can be
adjusted or further looked into. Of course, this is a long, difficult
process, but by looking further into epigenetics, perhaps the field of
psychological disorders can be further explored.