Animations of unseeable biology
-
0:00 - 0:06What I'm going to show you
are the astonishing molecular machines -
0:06 - 0:09that create the living
fabric of your body. -
0:09 - 0:13Now molecules are really, really tiny.
-
0:13 - 0:16And by tiny, I mean really.
-
0:17 - 0:19They're smaller
than a wavelength of light, -
0:19 - 0:21so we have no way
to directly observe them. -
0:22 - 0:24But through science,
we do have a fairly good idea -
0:24 - 0:26of what's going on
down at the molecular scale. -
0:27 - 0:30So what we can do is actually
tell you about the molecules, -
0:30 - 0:33but we don't really have a direct way
of showing you the molecules. -
0:33 - 0:35One way around this is to draw pictures.
-
0:35 - 0:38And this idea is actually nothing new.
-
0:38 - 0:40Scientists have always created pictures
-
0:40 - 0:43as part of their thinking
and discovery process. -
0:43 - 0:46They draw pictures
of what they're observing with their eyes, -
0:46 - 0:48through technology
like telescopes and microscopes, -
0:48 - 0:51and also what they're thinking
about in their minds. -
0:51 - 0:52I picked two well-known examples,
-
0:52 - 0:56because they're very well-known
for expressing science through art. -
0:56 - 1:00And I start with Galileo,
who used the world's first telescope -
1:00 - 1:01to look at the Moon.
-
1:01 - 1:03And he transformed
our understanding of the Moon. -
1:03 - 1:05The perception in the 17th century
-
1:05 - 1:07was the Moon was a perfect
heavenly sphere. -
1:08 - 1:11But what Galileo saw
was a rocky, barren world, -
1:11 - 1:13which he expressed
through his watercolor painting. -
1:13 - 1:16Another scientist with very big ideas,
-
1:16 - 1:19the superstar of biology
is Charles Darwin. -
1:19 - 1:21And with this famous entry
in his notebook, -
1:21 - 1:24he begins in the top left-hand
corner with, "I think," -
1:24 - 1:27and then sketches out
the first tree of life, -
1:27 - 1:29which is his perception
of how all the species, -
1:29 - 1:33all living things on Earth are connected
through evolutionary history -- -
1:33 - 1:36the origin of species
through natural selection -
1:36 - 1:38and divergence
from an ancestral population. -
1:39 - 1:40Even as a scientist,
-
1:40 - 1:43I used to go to lectures
by molecular biologists -
1:43 - 1:46and find them completely incomprehensible,
-
1:46 - 1:48with all the fancy technical
language and jargon -
1:48 - 1:50that they would use
in describing their work, -
1:50 - 1:53until I encountered
the artworks of David Goodsell, -
1:53 - 1:56who is a molecular biologist
at the Scripps Institute. -
1:56 - 2:00And his pictures -- everything's accurate
and it's all to scale. -
2:00 - 2:02And his work illuminated for me
-
2:02 - 2:04what the molecular world
inside us is like. -
2:05 - 2:07So this is a transection through blood.
-
2:07 - 2:10In the top left-hand corner,
you've got this yellow-green area. -
2:10 - 2:13The yellow-green area is the fluid
of blood, which is mostly water, -
2:13 - 2:16but it's also antibodies, sugars,
hormones, that kind of thing. -
2:16 - 2:19And the red region is a slice
into a red blood cell. -
2:19 - 2:20And those red molecules are hemoglobin.
-
2:21 - 2:23They are actually red;
that's what gives blood its color. -
2:23 - 2:25And hemoglobin acts as a molecular sponge
-
2:25 - 2:27to soak up the oxygen in your lungs
-
2:27 - 2:29and then carry it
to other parts of the body. -
2:29 - 2:32I was very much inspired
by this image many years ago, -
2:32 - 2:34and I wondered whether
we could use computer graphics -
2:34 - 2:36to represent the molecular world.
-
2:36 - 2:37What would it look like?
-
2:37 - 2:38And that's how I really began.
-
2:39 - 2:40So let's begin.
-
2:40 - 2:43This is DNA in its classic
double helix form. -
2:43 - 2:46And it's from X-ray crystallography,
so it's an accurate model of DNA. -
2:46 - 2:49If we unwind the double helix
and unzip the two strands, -
2:49 - 2:51you see these things that look like teeth.
-
2:51 - 2:53Those are the letters of genetic code,
-
2:53 - 2:55the 25,000 genes
you've got written in your DNA. -
2:55 - 2:58This is what they typically talk about --
the genetic code -- -
2:58 - 3:00this is what they're talking about.
-
3:00 - 3:03But I want to talk about
a different aspect of DNA science, -
3:03 - 3:05and that is the physical nature of DNA.
-
3:05 - 3:07It's these two strands
that run in opposite directions -
3:07 - 3:10for reasons I can't go into right now.
-
3:10 - 3:12But they physically run
in opposite directions, -
3:12 - 3:16which creates a number of complications
for your living cells, -
3:16 - 3:17as you're about to see,
-
3:17 - 3:19most particularly
when DNA is being copied. -
3:19 - 3:21And so what I'm about to show you
-
3:21 - 3:25is an accurate representation
of the actual DNA replication machine -
3:25 - 3:27that's occurring right now
inside your body, -
3:27 - 3:29at least 2002 biology.
-
3:29 - 3:32So DNA's entering the production line
from the left-hand side, -
3:33 - 3:36and it hits this collection,
these miniature biochemical machines, -
3:36 - 3:39that are pulling apart the DNA strand
and making an exact copy. -
3:39 - 3:43So DNA comes in and hits this blue,
doughnut-shaped structure -
3:43 - 3:45and it's ripped apart
into its two strands. -
3:45 - 3:47One strand can be copied directly,
-
3:47 - 3:50and you can see these things
spooling off to the bottom there. -
3:50 - 3:52But things aren't so simple
for the other strand -
3:52 - 3:54because it must be copied backwards.
-
3:54 - 3:56So it's thrown out
repeatedly in these loops -
3:56 - 4:00and copied one section at a time,
creating two new DNA molecules. -
4:00 - 4:06Now you have billions of this machine
right now working away inside you, -
4:06 - 4:08copying your DNA with exquisite fidelity.
-
4:09 - 4:10It's an accurate representation,
-
4:10 - 4:14and it's pretty much at the correct speed
for what is occurring inside you. -
4:14 - 4:17I've left out error correction
and a bunch of other things. -
4:17 - 4:18(Laughter)
-
4:18 - 4:21This was work from a number of years ago--
-
4:21 - 4:22Thank you.
-
4:22 - 4:23(Applause)
-
4:23 - 4:25This is work from a number of years ago,
-
4:25 - 4:27but what I'll show you next
is updated science, -
4:27 - 4:29it's updated technology.
-
4:29 - 4:30So again, we begin with DNA.
-
4:30 - 4:32And it's jiggling and wiggling there
-
4:32 - 4:34because of the surrounding
soup of molecules, -
4:34 - 4:36which I've stripped away
so you can see something. -
4:36 - 4:39DNA is about two nanometers across,
which is really quite tiny. -
4:39 - 4:41But in each one of your cells,
-
4:41 - 4:44each strand of DNA is about
30 to 40 million nanometers long. -
4:44 - 4:48So to keep the DNA organized
and regulate access to the genetic code, -
4:48 - 4:50it's wrapped around these
purple proteins -- -
4:50 - 4:52or I've labeled them purple here.
-
4:52 - 4:54It's packaged up and bundled up.
-
4:54 - 4:56All this field of view
is a single strand of DNA. -
4:57 - 5:00This huge package of DNA
is called a chromosome. -
5:00 - 5:02And we'll come back
to chromosomes in a minute. -
5:02 - 5:04We're pulling out, we're zooming out,
-
5:05 - 5:06out through a nuclear pore,
-
5:06 - 5:10which is the gateway to this compartment
that holds all the DNA, -
5:10 - 5:11called the nucleus.
-
5:12 - 5:16All of this field of view
is about a semester's worth of biology, -
5:16 - 5:17and I've got seven minutes,
-
5:17 - 5:20So we're not going to be
able to do that today? -
5:20 - 5:22No, I'm being told, "No."
-
5:22 - 5:26This is the way a living cell
looks down a light microscope. -
5:26 - 5:29And it's been filmed under time-lapse,
which is why you can see it moving. -
5:29 - 5:31The nuclear envelope breaks down.
-
5:31 - 5:33These sausage-shaped things
are the chromosomes, -
5:33 - 5:34and we'll focus on them.
-
5:34 - 5:38They go through this very striking motion
that is focused on these little red spots. -
5:39 - 5:43When the cell feels it's ready to go,
it rips apart the chromosome. -
5:43 - 5:45One set of DNA goes to one side,
-
5:45 - 5:47the other side gets
the other set of DNA -- -
5:47 - 5:49identical copies of DNA.
-
5:49 - 5:51And then the cell splits down the middle.
-
5:51 - 5:54And again, you have billions of cells
undergoing this process -
5:54 - 5:56right now inside of you.
-
5:56 - 5:59Now we're going to rewind
and just focus on the chromosomes, -
5:59 - 6:01and look at its structure and describe it.
-
6:02 - 6:04So again, here we are
at that equator moment. -
6:05 - 6:07The chromosomes line up.
-
6:07 - 6:08And if we isolate just one chromosome,
-
6:08 - 6:11we're going to pull it out
and have a look at its structure. -
6:11 - 6:14So this is one of the biggest
molecular structures that you have, -
6:14 - 6:17at least as far as we've discovered
so far inside of us. -
6:18 - 6:20So this is a single chromosome.
-
6:20 - 6:23And you have two strands of DNA
in each chromosome. -
6:23 - 6:24One is bundled up into one sausage.
-
6:24 - 6:27The other strand is bundled up
into the other sausage. -
6:27 - 6:31These things that look like whiskers
that are sticking out from either side -
6:31 - 6:33are the dynamic scaffolding of the cell.
-
6:33 - 6:36They're called microtubules,
that name's not important. -
6:36 - 6:38But we're going to focus on
the region labeled red here -- -
6:38 - 6:41and it's the interface between
the dynamic scaffolding -
6:41 - 6:42and the chromosomes.
-
6:42 - 6:45It is obviously central
to the movement of the chromosomes. -
6:45 - 6:49We have no idea, really,
as to how it's achieving that movement. -
6:49 - 6:51We've been studying this thing
they call the kinetochore -
6:52 - 6:54for over a hundred years
with intense study, -
6:54 - 6:56and we're still just beginning
to discover what it's about. -
6:56 - 6:59It is made up of about
200 different types of proteins, -
6:59 - 7:01thousands of proteins in total.
-
7:02 - 7:05It is a signal broadcasting system.
-
7:05 - 7:07It broadcasts through chemical signals,
-
7:07 - 7:10telling the rest of the cell
when it's ready, -
7:10 - 7:12when it feels that everything
is aligned and ready to go -
7:12 - 7:14for the separation of the chromosomes.
-
7:14 - 7:18It is able to couple onto the growing
and shrinking microtubules. -
7:18 - 7:21It's involved with the growing
of the microtubules, -
7:21 - 7:23and it's able to transiently
couple onto them. -
7:24 - 7:26It's also an attention-sensing system.
-
7:26 - 7:28It's able to feel when the cell is ready,
-
7:28 - 7:30when the chromosome
is correctly positioned. -
7:30 - 7:34It's turning green here because it feels
that everything is just right. -
7:34 - 7:36And you'll see,
there's this one little last bit -
7:36 - 7:38that's still remaining red.
-
7:38 - 7:40And it's walked away
down the microtubules. -
7:42 - 7:45That is the signal broadcasting system
sending out the stop signal. -
7:45 - 7:48And it's walked away --
I mean, it's that mechanical. -
7:48 - 7:49It's molecular clockwork.
-
7:49 - 7:52This is how you work
at the molecular scale. -
7:53 - 7:55So with a little bit
of molecular eye candy, -
7:55 - 7:56(Laughter)
-
7:56 - 7:58we've got kinesins, the orange ones.
-
7:58 - 8:01They're little molecular courier
molecules walking one way. -
8:01 - 8:04And here are the dynein,
they're carrying that broadcasting system. -
8:04 - 8:06And they've got their long legs
-
8:06 - 8:08so they can step around
obstacles and so on. -
8:08 - 8:11So again, this is all derived
accurately from the science. -
8:11 - 8:13The problem is we can't show it
to you any other way. -
8:13 - 8:18Exploring at the frontier of science,
at the frontier of human understanding, -
8:18 - 8:19is mind-blowing.
-
8:21 - 8:22Discovering this stuff
-
8:22 - 8:25is certainly a pleasurable
incentive to work in science. -
8:26 - 8:28But most medical researchers --
-
8:29 - 8:33discovering the stuff is simply steps
along the path to the big goals, -
8:33 - 8:37which are to eradicate disease,
to eliminate the suffering -
8:37 - 8:39and the misery that disease causes
-
8:39 - 8:41and to lift people out of poverty.
-
8:41 - 8:42Thank you.
-
8:42 - 8:48(Applause)
- Title:
- Animations of unseeable biology
- Speaker:
- Drew Berry
- Description:
-
We have no ways to directly observe molecules and what they do -- Drew Berry wants to change that. At TEDxSydney he shows his scientifically accurate (and entertaining!) animations that help researchers see unseeable processes within our own cells.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 08:47
Krystian Aparta commented on English subtitles for Animations of unseeable biology | ||
Krystian Aparta edited English subtitles for Animations of unseeable biology | ||
Krystian Aparta edited English subtitles for Animations of unseeable biology | ||
TED edited English subtitles for Animations of unseeable biology | ||
Regina Chu edited English subtitles for Animations of unseeable biology | ||
TED added a translation |
Krystian Aparta
The English transcript was updated on 11/24/2016.