字幕表 動画を再生する
In high school, we learned ACGT ACGT ACGT Adenine, cytosine, guanine, thymine. These
are the bases… And yet… there's more to this tiny story than meets the eye. OR the
rest of the body.
In April of 1953, the double-helix of deoxyribonucleic acid or DNA was announced in the journal "Nature."
The discovery of the building blocks of life was celebrated worldwide, and earned James
Watson and Watson Crick a Nobel Prize, which they shared with Maurice Wilkins. Shout out
to Rosalind Franklin for discovering the final piece of the Watson-Crick model, the helical
structure. Tons of scientists and scholars worked on the discovery of hereditary biology
for almost a century. If you've taken high school biology, you know DNA and genes are
used to create proteins which carry out physiological functions in cells. Watson and Crick's final
model indicated just HOW this molecule is the most basic structure life -- we thought
DNA was like, the One Ring that rules them all… but new research from the University
of Edinburgh, published in Science, found DNA might just be a part of the puzzle of
biological inheritance.
All humans carry 2 meters of DNA in each of their cell nuclei (except in sperm and egg
cells, of course). That's a fantastic amount of genetic information. In fact, if you do
the math, the human body contains 100 trillion meters of DNA per person. That's enough to
make a line of DNA to the sun and back 300 times. Similar to a rope, it can get tangled
if you don't store it properly, so nature figured out an efficient means of storage.
The DNA molecule carries a negative charge, so (like my hair to a balloon) DNA is attracted
to these positively charged proteins called histones and form what looks like little beads
on a string. We've known this for decades, but this new study found these histones are
more than they seem.
DNA wraps itself around the histones like a spool, storing the DNA safely and decreasing
its length by seven times, but it's not just for storage. It also can determine what genes
near each histone are switched on or off. Now, for the first time ever, research uncovered
histones can affect how DNA is expressed not just in me, but in my offspring! This discovery
finds that DNA isn't the lonely hero of inherited traits after all, but a member of a team.
Assuming I'm a yeast cell, of course.
By manipulating the histones inside yeast cells, researchers were able to follow how
that affected the gene expression from one generation to the next. Essentially, if they
messed with a histone, and that switched off some genes nearby, they could see those same
switches were off in the next generation of yeast too! Proving the histones are inherited
and were affecting gene expression in the yeast's offspring.
Histones' effects on gene expression was known, but that it is inherited is groundbreaking!
Histones are a major driver of epigenetics through a process called histone methylation.
When amino acids link up with histones, they'll help switch on or off genes and which affects
genetic expression, DNA transcription (or copying), and thus ultimately the organism
as a whole. And it's inherited! We already know histone methylation can be affected by
stress and diet; that's basic epigenetics, but if scientists can show histones are inherited
like DNA in humans, then we might be getting our first glimpse into how YOUR stress could
affect your kids, and their kids! WOW!
Does this stress you out? STOP BEING STRESSED! Its affecting your grandkids!
On the other hand, so what if you're stressed. We're getting so good at genetic modifications,
we should be able to just go in and tweak our kids anyway? Right? Julianna, debate the
merits of designer genetic babies in THIS video (soundup)
subscribe. like. love. hugs. thanks for watching dnews.