What I'm going to show you are the astonishing molecular machines that create the living fabric of your body. Now molecules are really, really tiny. And by tiny, I mean really. They're smaller than a wavelength of light, so we have no way to directly observe them. But through science, we do have a fairly good idea of what's going on down at the molecular scale. So what we can do is actually tell you about the molecules, but we don't really have a direct way of showing you the molecules.
我要向各位展示 驚人的分子機器 這些分子在你體內形成活的組織。 分子非常、非常的小 說它小, 我是指真的很小。 他們比光的波長還小, 因此我們無法以肉眼直接觀察它們。 但透過科學,我們的確對身體 在分子層級上正在發生的事,有一定程度的了解。 我們雖能直接告訴你有關這些分子的種種, 但我們真的沒有辦法直接把分子拿給你看。
One way around this is to draw pictures. And this idea is actually nothing new. Scientists have always created pictures as part of their thinking and discovery process. They draw pictures of what they're observing with their eyes, through technology like telescopes and microscopes, and also what they're thinking about in their minds. I picked two well-known examples, because they're very well-known for expressing science through art.
畫圖是一個解決的方法。 而這也不是什麼新鮮的想法。 科學家一向都以圖片 來闡釋他們的思考及發現新知的過程。 他們以圖畫來呈現他們透過肉眼 或透過望遠鏡及顯微鏡等科技觀察到的東西, 以及他們在腦海裡思索的事物。 我舉兩個很有名的例子, 因為他們在以藝術表達科學這方面很有名。
And I start with Galileo, who used the world's first telescope to look at the Moon. And he transformed our understanding of the Moon. The perception in the 17th century was the Moon was a perfect heavenly sphere. But what Galileo saw was a rocky, barren world, which he expressed through his watercolor painting.
首先是伽利略 他用世界首座望遠鏡 來觀察月亮, 他改變了我們對月亮的了解。 在十七世紀時的概念裡 月亮是完美無缺的球體。 但伽利略所看到的卻是一個坑坑洞洞的貧瘠世界, 他以水彩畫出他的觀察。
Another scientist with very big ideas, the superstar of biology is Charles Darwin. And with this famous entry in his notebook, he begins in the top left-hand corner with, "I think," and then sketches out the first tree of life, which is his perception of how all the species, all living things on Earth are connected through evolutionary history -- the origin of species through natural selection and divergence from an ancestral population.
另外一位很有想法的科學家, 就是生物學的超級名星查爾斯.達爾文。 在他的筆記裡,這張有名的插圖 以在左上角寫著「我認為」開始 然後畫出歷史上第一個演化樹。 這是他對世上 所有的物種、所有的生物 如何被演化的歷史串連的觀點, 亦即物種如何經過天擇源起, 並由始祖群體分支出新物種。
Even as a scientist, I used to go to lectures by molecular biologists and find them completely incomprehensible, with all the fancy technical language and jargon that they would use in describing their work, until I encountered the artworks of David Goodsell, who is a molecular biologist at the Scripps Institute. And his pictures -- everything's accurate and it's all to scale. And his work illuminated for me what the molecular world inside us is like.
即使像我身為科學家 以前聽分子生物學家演講時, 我仍然不能完全了解 那些科學家在描述他們的研究時 所使用的專有名詞及行話。 直到我看到大衛‧顧塞爾的作品, 他是美國斯克利浦斯研究所的分子生物學家。 他所畫的圖 每一樣都畫的很正確且按著比例 他的作品使我了解 我們體內的分子世界是什麼樣子。
So this is a transection through blood. In the top left-hand corner, you've got this yellow-green area. The yellow-green area is the fluid of blood, which is mostly water, but it's also antibodies, sugars, hormones, that kind of thing. And the red region is a slice into a red blood cell. And those red molecules are hemoglobin. They are actually red; that's what gives blood its color. And hemoglobin acts as a molecular sponge to soak up the oxygen in your lungs and then carry it to other parts of the body.
這是血液組織橫切面圖。 圖片左上方有一塊黃綠色的地方, 這塊黃綠色的地方是血漿,絕大部份是水, 但也有抗體、糖、 賀爾蒙等這些東西。 而紅色的區域為紅血球切面。 那些紅色的分子昰血紅素。 他們真的是紅色的,血液因此呈現紅色。 血紅素扮演分子海綿的角色, 吸收肺所吸進的氧氣 然後帶到身體其它部位。
I was very much inspired by this image many years ago, and I wondered whether we could use computer graphics to represent the molecular world. What would it look like? And that's how I really began. So let's begin.
許多年前,我從這張圖片得到許多靈感。 我思索著如何以電腦製圖 來呈現分子世界。 它會是什麼樣子呢? 我就是這樣開始畫作的。現在就來看吧。 這是DNA典型的雙股螺旋結構,
This is DNA in its classic double helix form. And it's from X-ray crystallography, so it's an accurate model of DNA. If we unwind the double helix and unzip the two strands, you see these things that look like teeth. Those are the letters of genetic code, the 25,000 genes you've got written in your DNA. This is what they typically talk about -- the genetic code -- this is what they're talking about. But I want to talk about a different aspect of DNA science, and that is the physical nature of DNA. It's these two strands that run in opposite directions for reasons I can't go into right now. But they physically run in opposite directions, which creates a number of complications for your living cells, as you're about to see, most particularly when DNA is being copied.
因為是從X光晶體結構圖看到的 所以這是正確的DNA模型。 如果我們把雙股螺旋伸展拉直,如拉鍊拉開, 這看起來像牙齒的東西 是遺傳密碼的字母, 構成你的DNA中二萬五千個基因。 這是老生常談了 遺傳密碼,非常普遍的話題。 但是我想從另一方面來談DNA, 就是DNA的物理性質。 這兩鏈互以相反方向排列, 我現在先不解釋為什麼, 但是這兩鏈以相反方向排列 使得你的活細胞變的很複雜 --你馬上會看到-- 特別是在DNA複製的時候。
And so what I'm about to show you is an accurate representation of the actual DNA replication machine that's occurring right now inside your body, at least 2002 biology. So DNA's entering the production line from the left-hand side, and it hits this collection, these miniature biochemical machines, that are pulling apart the DNA strand and making an exact copy. So DNA comes in and hits this blue, doughnut-shaped structure and it's ripped apart into its two strands. One strand can be copied directly, and you can see these things spooling off to the bottom there. But things aren't so simple for the other strand because it must be copied backwards. So it's thrown out repeatedly in these loops and copied one section at a time, creating two new DNA molecules.
我即將播放的影片 很準確地畫出了 在你體內運行中的DNA複製機制, 這圖是基於2002年生物學所畫的。 所以DNA從左手邊進入生產線 碰到這個組合物,這些小型生化機器 把DNA雙股分開並複製完全相同的副本。 所以DNA進來 碰到這個藍色甜甜圈形狀的結構體, 這個結構體把兩股長鏈分離。 其中一股可以直接複製, 你可以看到複製品從底下合成出來, 但對於另外一鏈事情就沒這麼簡單了, 因為它必須反向複製。 所以這些複製品不斷地從這些圈圈裡丟出來, 一次複製一段, 創造出兩個新的DNA分子。
Now you have billions of this machine right now working away inside you, copying your DNA with exquisite fidelity. It's an accurate representation, and it's pretty much at the correct speed for what is occurring inside you. I've left out error correction and a bunch of other things.
在你的身體裡有無數個這種機器, 現在就在你體內工作, 以最精緻的保真度複製你的DNA。 這個影片畫的很正確, 並與你體內複製的速度極為相近。 我沒有畫出細胞的校正機制及其他的東西。
(Laughter)
這是好多年前的作品。
This was work from a number of years ago-- Thank you.
謝謝。 這是好多年前的作品,
(Applause)
This is work from a number of years ago, but what I'll show you next is updated science, it's updated technology. So again, we begin with DNA. And it's jiggling and wiggling there because of the surrounding soup of molecules, which I've stripped away so you can see something. DNA is about two nanometers across, which is really quite tiny. But in each one of your cells, each strand of DNA is about 30 to 40 million nanometers long. So to keep the DNA organized and regulate access to the genetic code, it's wrapped around these purple proteins -- or I've labeled them purple here. It's packaged up and bundled up. All this field of view is a single strand of DNA. This huge package of DNA is called a chromosome. And we'll come back to chromosomes in a minute.
我即將給你看的昰以最新科學及技術所畫的動畫。 所以跟剛剛一樣,我們從DNA開始。 它在這搖來搖去,因為它被其它分子所包圍。 我沒畫出其他分子,這樣才看的清楚。 DNA約二奈米寬, 真的非常非常小, 但是在你的每一個細胞內, DNA的每一鏈都有三四千萬奈米長。 所以為了組織DNA並調控遺傳密碼讀取, DNA包圍著這些紫色的蛋白質 --或者是說我把它塗成紫色-- 他們捆包起來。 在這裡看到的都是單鏈DNA。 這整捆的DNA叫做染色體。 我們等一下再來談染色體。
We're pulling out, we're zooming out, out through a nuclear pore, which is the gateway to this compartment that holds all the DNA, called the nucleus. All of this field of view is about a semester's worth of biology, and I've got seven minutes, So we're not going to be able to do that today? No, I'm being told, "No."
我們將鏡頭拉遠、縮小畫面, 穿過核孔, 核孔是到細胞核的通道, 而DNA就在細胞核裡。 你現在所看到的, 要花一整個學期來上課,但我只有七分鐘。 所以我們今天能多談一些嗎? 不行,我得到的答案是不。
This is the way a living cell looks down a light microscope. And it's been filmed under time-lapse, which is why you can see it moving. The nuclear envelope breaks down. These sausage-shaped things are the chromosomes, and we'll focus on them. They go through this very striking motion that is focused on these little red spots. When the cell feels it's ready to go, it rips apart the chromosome. One set of DNA goes to one side, the other side gets the other set of DNA -- identical copies of DNA. And then the cell splits down the middle. And again, you have billions of cells undergoing this process right now inside of you.
這是從光學顯微鏡下看到的活細胞, 以延時技術拍下,所以你可以看到細胞在動。 核膜破裂, 這些像香腸形狀的東西就是染色體,這是我們的主題。 他們進行非常獨特的活動, 被這些紅點拉著走。 當細胞準備好要分裂 就把染色體分開。 一組DNA到這邊, 另一組DNA到另外一邊, 一模一樣的兩組DNA, 然後細胞從中分開。 再說一次,你的體內有無數的細胞 現在正在做這樣的事。
Now we're going to rewind and just focus on the chromosomes, and look at its structure and describe it. So again, here we are at that equator moment. The chromosomes line up. And if we isolate just one chromosome, we're going to pull it out and have a look at its structure. So this is one of the biggest molecular structures that you have, at least as far as we've discovered so far inside of us. So this is a single chromosome. And you have two strands of DNA in each chromosome. One is bundled up into one sausage. The other strand is bundled up into the other sausage.
現在我們倒帶,特別只看染色體部分, 來講一下它的結構。 所以再看一次,在細胞分裂,赤道板形成的時候, 染色體排列成一直線。 如果我們拿出其中一條染色體, 我們把它抽出來看看它的結構。 這是你體內最大的分子結構, 至少是目前所發現的分子中最大的。 這是一條染色體, 每條染色體有兩鏈DNA。 這一鏈捆綁成一條香腸, 另一鏈也捆綁成一條香腸。
These things that look like whiskers that are sticking out from either side are the dynamic scaffolding of the cell. They're called microtubules, that name's not important. But we're going to focus on the region labeled red here -- and it's the interface between the dynamic scaffolding and the chromosomes. It is obviously central to the movement of the chromosomes. We have no idea, really, as to how it's achieving that movement.
這些看起來像觸鬚的東西從兩端穿出, 是細胞的動態鷹架。 這些叫微管,名字本身不重要, 重點是這些紅色的部分,是我把它塗成紅的, 這個介面, 介於細胞鷹架及染色體中間。 很明顯是染色體移動的中心。 我們真的不知道它怎麼讓DNA移動。
We've been studying this thing they call the kinetochore for over a hundred years with intense study, and we're still just beginning to discover what it's about. It is made up of about 200 different types of proteins, thousands of proteins in total. It is a signal broadcasting system. It broadcasts through chemical signals, telling the rest of the cell when it's ready, when it feels that everything is aligned and ready to go for the separation of the chromosomes. It is able to couple onto the growing and shrinking microtubules.
我們一直在研究這個叫動粒的東西, 一百多年來的緊密研究, 但我們才剛剛開始了解它的功用。 它由200種不同的蛋白質組成, 總共有數萬個蛋白質。 它是信號廣播系統, 透過化學信號來廣播, 告訴其他的細胞組織, 一切都已排列整齊,準備好 可以讓染色體分離了。 它能夠與伸長或縮小的微管結合,
It's involved with the growing of the microtubules, and it's able to transiently couple onto them. It's also an attention-sensing system. It's able to feel when the cell is ready, when the chromosome is correctly positioned. It's turning green here because it feels that everything is just right. And you'll see, there's this one little last bit that's still remaining red. And it's walked away down the microtubules. That is the signal broadcasting system sending out the stop signal. And it's walked away -- I mean, it's that mechanical. It's molecular clockwork.
它與微管的生長有關, 並短暫地與微管結合。 它也是一種傳感系統。 它可以感覺到細胞已經準備好了, 就是當染色體排在正確的位置的時候。 在這裡它變成綠色, 因為它覺得所有的事都恰到好處。 然後你看,這裡還有一個小小的點, 還是呈現紅色。 它離開了,順著微管往下走。 這是信號廣播系統告訴大家要停了。 它就走開, 真的,就是這麼機械化。 它就像分子的發條。
This is how you work at the molecular scale. So with a little bit of molecular eye candy,
你在分子層級上就是這樣就是這樣運作。 所以利用一些賞心悅目的分子解釋,
(Laughter)
我們有驅動蛋白,是這些橘色點,
we've got kinesins, the orange ones. They're little molecular courier molecules walking one way. And here are the dynein, they're carrying that broadcasting system. And they've got their long legs so they can step around obstacles and so on. So again, this is all derived accurately from the science. The problem is we can't show it to you any other way.
他們像是小小的分子信差,單向滑行。 這些是動力蛋白,運載那個信號廣播系統。 他們腳很長,所以可以避開障礙物旁走。 這些也是照著科學研究, 所畫出的動畫。 問題在於我們沒辦法用其他的方法呈現。
Exploring at the frontier of science, at the frontier of human understanding, is mind-blowing. Discovering this stuff is certainly a pleasurable incentive to work in science. But most medical researchers -- discovering the stuff is simply steps along the path to the big goals, which are to eradicate disease, to eliminate the suffering and the misery that disease causes and to lift people out of poverty.
在科學發展的最前線, 及在人類知識的極限探索, 昰對思想的震撼。 發現這些東西, 的確對科學研究帶來愉快的動力。 但是對絕大多數的醫學研究者而言, 發現這些東西 只是向更大目標邁進的一小步, 就是希望能消滅疾病, 減少疾病所帶來的痛苦及不幸, 並且將人們帶離貧窮。
Thank you.
謝謝。
(Applause)
(掌聲)