More to our Junk DNA than meets the eye | Jay W. SHIN | TEDxKobe


Translator: Hideki Yakushiji
Reviewer: Claire Ghyselen Good morning. I am a cell biologist from RIKEN Yokohama. Today I am going to tell you about junk. Gomi! Yes. Junk can be considered
as something useless or serving no purpose. Let me give you an example. A food that is considered
having very little nutrition value, we call that junk food. Or you open our post box,
and you find piles of advertisements, we call that junk mail. But you might be wondering why a scientist is going to
tell you about junk today. I am not going to talk
about any ordinary junk but junk that is found inside our DNA. DNA can be found inside our cells
and they are the blueprints of life. DNA contains all the genetic information
that help us to start life, to maintain our life, protect our life,
and even end our life. But there is a mystery
hidden behind our DNA. All of these processes
that I just described to you are controlled by genes. But our genes can only be found
in 2% of our DNA. But there is more. If you were to take DNA
and extract it from your cell from single cell of your body, and you stretch out your DNA
as long as you can, that can be as long as two meters long. What is more amazing is
that if you were to take DNA from all of the cells in our human body, and combine them all together,
and stretch it as far as you can, it will go from this earth to the sun
and back 200 times. That’s the amount of DNA
that we are carrying inside our body. But as I said,
this 2% can only be found to describe the most important part
of the genetic controls in our life. You will be wondering
how about this remaining 98%, this non-coding regions of our DNA. For the longest time,
ever since the 1970s, many scientists thought that this part
of our DNA was considered junk or useless. And that really got me curious because when I first heard this
as a high school student in biology class, something didn’t really feel right. You know, I didn’t feel good that I was
carrying all this  junk in my body, and something had to be
more than just uselessness. So, that really got me curious
and want to venture into my research. I wanted to understand what is hidden
behind this part of our DNA. Over the past several years, our lab and many other labs
around the world have discovered that there is far more information hidden
in this area than previously thought. DNA actually is not
two dimensional linear. But inside our cells,
they can actually form three dimensional interactions. And what has been shown is
that these non-coding regions of our DNA are in close contact
with the protein-coding regions to regulate the gene expression. They can switch on or switch off the gene. What’s far more interesting is
that many of the mutations, the changes that occur in our DNA
that can cause disease are also found in this
non-coding region of our DNA. Mutations that can cause cancer,
or autoimmune disease, or Alzheimer’s or Parkinson’s, these mutations are found
in the non-coding DNA regions and they are actually interfering [with]
the control of the central genes to life. And by these mutations, we are finding very devastating
consequences to our daily activities. We quickly realized that in order
to understand the full extent of our life, we need to look beyond this 2%
and explore the unknown. There is more that I want
to share you today. DNA cannot only generate RNA. So, RNA is very central
part of our process, and RNA can be considered
as a cousin to our DNA. What has been known is
that RNA is required to make proteins. But we’ve realized is that
in this non-coding regions of our DNA, they can also generate RNA. But what’s unique about this,
is that this RNA do not make proteins. So, there must be something more
that this protein is doing. In order to understand
this non-coding RNA, many laboratories around the world,
including ourselves, have started to characterize them. Let me give you a couple of examples
of what non-coding RNA can actually do. One of the things it can do is
that it can act as a connector. It can bring two proteins together
to join into one simple complex. You can imagine it
like a Shinkansen train. You have two train carriages
and you need a little connector in-between to bring these two carriages together. Just like that, these non-coding RNAs
are able to bring two proteins together. Therefore, these proteins then
can be functional inside our cells. Another example of this non-coding RNA
is that it can act as a GPS system. This non-coding RNA contains
zip code in the genetic code, that will help its proteins
to navigate inside the cells and direct them to the place
where they need to go. These new mechanisms that we are
discovering about this non-coding RNA, is rebuilding new biology inside our cells
that we didn’t know before. And because of these pathways, we are also figuring out new ways
to find solutions for therapeutic purpose. We are realizing these non-coding RNAs
are far more than just junk, that they are actually
the control centers of our DNA, and regulating a lot of processes
that we didn’t know before. To truly understand the blueprint of life,
we have to look beyond and start to explore more
what is hidden in these regions. Although I only highlighted
two examples today, through collective effort
from our laboratory and around the world we discovered in fact 25,000 or more
of these types of non-coding RNAs. And we only know a very small fraction of these non-coding RNAs
and their functions. So, we are just scratching
the surface of the iceberg. In order to understand
full complexity of our live, we need to dive deep and explore
this uncharted territory. To achieve this and to understand
to full characterization of long non-coding RNA in the cells,
we have started a new project. One of the aims is to build, to achieve this,
by building a robotic system that can perform
high throughput screening. What it does is that we are able to remove
these non-coding RNAs from our cells, one by one. And you can use DNA sequencers
to measure what are the genes that switch on and switch off
inside the cells. Just to illustrate this idea, imagine a car made up
of multiple components. These components can be
your steering wheels, brake pedals or nuts and bolts,
that make up the car. While the car is in motion, you start
to remove one component at a time. What will happen to a car? Will it steer away?
Would the driver feel safe? By measuring these activities, we can understand how important
this one component can be inside the car. So in the same token,
we are using a similar approach where we are removing one non-coding RNA
at a time inside the cell, to understand how important
a particular non-coding RNA is to the make up of the cells. Over the past three years, we have characterized
many of these non-coding RNAs. We are using in-depth
computational analysis to understand the complexity of the life. But of course none of these
can be achieved alone. And this really is a big project
and a whole global effort is required. To achieve that we have started
an international consortium called “FANTOM6.” It is a consortium of scientists
all around the world, aiming to build
the most comprehensive catalog of these long non-coding RNAs. The consortium consists of hundreds
of scientists around the world, from US, Germany, UK and Australia. And I’ve been truly honored
to co-lead this consortium together with Drs. Piero Carninci
and Michiel de Hoon at the RIKEN Institute. There’s a lot of activities ahead of us and we are all thrilled
to be a part of this journey. We came a very long way
from the time when we labeled these DNA : “Junk” But now, we are really starting
to redefine the meaning of DNA. Through discovery of new non-coding RNAs,
we are entering into whole new world that no one has gone before. My dream is that this catalog
of non-coding RNA will be the building block
that, can spiral new inspiration and that it will help
to improve our health, and provide new solutions
to cure diseases. Thank for your attention. (Applause)

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