The wonders of the molecular world, animated | Janet Iwasa

譯者: Lilian Chiu 審譯者: SF Huang

I live in Utah,

我住的猶他州，

a place known for having some of the most awe-inspiring

因有著世界上最讓人讚嘆的

natural landscapes on this planet.

一些自然景觀而聞名。

It's easy to be overwhelmed by these amazing views,

人們常震懾於這壯麗的觀景，

and to be really fascinated by these sometimes alien-looking formations.

且深深著迷於這些有時看起來 如同異世界的奇景。

As a scientist, I love observing the natural world.

身為科學家，我很愛觀察大自然。

But as a cell biologist,

但，身為細胞生物學家，

I'm much more interested in understanding the natural world

我更感興趣的是去瞭解

at a much, much smaller scale.

極小尺度下的自然界。

I'm a molecular animator, and I work with other researchers

我是分子動畫師，我和研究者合作

to create visualizations of molecules that are so small,

將肉眼看不見的微小分子具象化。

they're essentially invisible.

These molecules are smaller than the wavelength of light,

這些分子比光的波長還小，

which means that we can never see them directly,

意即就算有最好的光學顯微鏡， 我們也無法直接看見它們，

even with the best light microscopes.

So how do I create visualizations of things

我要如何將看不見的東西視像化？

that are so small we can't see them?

Scientists, like my collaborators,

科學家，比如我的合作夥伴，

can spend their entire professional careers

會終其職涯

working to understand one molecular process.

窮究一個分子過程。

To do this, they carry out a series of experiments

他們的做法是進行一系列的實驗，

that each can tell us a small piece of the puzzle.

每個實驗都能告訴我們 拼圖的一小部分。

One kind of experiment can tell us about the protein shape,

有的實驗可以告訴我們 蛋白質的形狀資訊，

while another can tell us

有的能告訴我們它可能 會和哪些蛋白質作用，

about what other proteins it might interact with,

and another can tell us about where it can be found in a cell.

有的能告訴我們它位於細胞何處。

And all of these bits of information can be used to come up with a hypothesis,

這些零星片段的資訊拼湊起來 可以讓我們彙整出一個假設，

a story, essentially, of how a molecule might work.

一個故事，說明分子如何運作。

My job is to take these ideas and turn them into an animation.

我的工作是要把這些想法製成動畫。

This can be tricky,

有時挺棘手，因為 分子其實會做些蠻瘋狂的事。

because it turns out that molecules can do some pretty crazy things.

But these animations can be incredibly useful for researchers

但這些動畫對研究者表達

to communicate their ideas of how these molecules work.

他們對於分子運作的想法非常有用。

They can also allow us to see the molecular world

這些動畫也讓我們能透過 他們的眼睛來看分子世界。

through their eyes.

I'd like to show you some animations,

讓我給大家看一些動畫，

a brief tour of what I consider to be some of the natural wonders

快速帶大家看一些我心目中的

分子世界自然奇景。

of the molecular world.

First off, this is an immune cell.

首先，這是免疫細胞。

These kinds of cells need to go crawling around in our bodies

這類細胞必須要在 我們體內到處爬來爬去，

in order to find invaders like pathogenic bacteria.

才能找到入侵者，比如病原菌。

This movement is powered by one of my favorite proteins

這種移動的動力來源 是我最愛的蛋白質之一，

called actin,

肌動蛋白，它是所謂 細胞骨架的一部分。

which is part of what's known as the cytoskeleton.

Unlike our skeletons,

和我們的骨骼不同，

actin filaments are constantly being built and taken apart.

肌動蛋白細絲一直不斷地 產製和拆解。

The actin cytoskeleton plays incredibly important roles in our cells.

肌動蛋白細胞骨架在我們的 細胞中扮演極重要的角色。

They allow them to change shape,

它們能讓細胞改變形狀，

to move around, to adhere to surfaces

四處移動、附著在表面上

and also to gobble up bacteria.

以及吃掉細菌。

Actin is also involved in a different kind of movement.

肌動蛋白也參與另一種不同的動作。

In our muscle cells, actin structures form these regular filaments

在肌肉細胞中，肌動蛋白結構 會形成這些細絲，

that look kind of like fabric.

看起來就像織物。

When our muscles contract, these filaments are pulled together

當我們的肌肉收縮， 這些細絲會被拉近，

and they go back to their original position

當肌肉放鬆時， 又回到原來的位置。

when our muscles relax.

Other parts of the cytoskeleton, in this case microtubules,

細胞骨架的其他部分， 比如這裡的微管，

are responsible for long-range transportation.

負責長程的運輸。

They can be thought of as basically cellular highways

可以把它視為細胞的高速公路，

that are used to move things from one side of the cell to the other.

把東西從細胞的此端運送到彼端。

Unlike our roads, microtubules grow and shrink,

和我們的道路不同， 微管會長大和縮小，

appearing when they're needed

需要它們時就會出現， 工作完成後就會消失。

and disappearing when their job is done.

The molecular version of semitrucks

分子版的半掛式卡車

are proteins aptly named motor proteins,

是被貼切稱為馬達蛋白的蛋白質，

that can walk along microtubules,

它能延著微管爬行，

dragging sometimes huge cargoes,

有時身後還可以拖著大型貨物，

like organelles, behind them.

比如胞器。

This particular motor protein is known as dynein,

這種馬達蛋白就是 一般所稱的動力蛋白，

and its known to be able to work together in groups

它們以團隊合作著稱，

that almost look, at least to me, like a chariot of horses.

至少我個人看起來覺得就像馬戰車。

As you see, the cell is this incredibly changing, dynamic place,

各位可以看到，細胞是個 不斷改變、保持動態的地方，

where things are constantly being built and disassembled.

東西經常在這裡被建造和拆除。

But some of these structures

不過，有些結構會比 其他結構更難拆除。

are harder to take apart than others, though.

需要再帶入特殊的力量，

And special forces need to be brought in

才能確保這些結構能及時被拆除。

in order to make sure that structures are taken apart in a timely manner.

That job is done in part by proteins like these.

這份工作有部分是由 像這樣的蛋白質來完成。

These donut-shaped proteins,

在細胞有中很多種 像這樣的甜甜圈型的蛋白質，

of which there are many types in the cell,

all seem to act to rip apart structures

它們似乎都會將個別蛋白質

by basically pulling individual proteins through a central hole.

拉進中間的洞孔藉撕扯來拆除結構。

When these kinds of proteins don't work properly,

如果這些蛋白質沒有 把它們的工作做好，

the types of proteins that are supposed to get taken apart

應該要被拆解的那些蛋白質

can sometimes stick together and aggregate

有時有可能會黏聚在一起，

and that can give rise to terrible diseases, such as Alzheimer's.

那就會造成很糟糕的疾病， 如阿茲海默症。

And now let's take a look at the nucleus,

現在，來看看細胞核，

which houses our genome in the form of DNA.

細胞核以 DNA 的形式 來儲藏基因組。

In all of our cells,

在我們所有的細胞中，

our DNA is cared for and maintained by a diverse set of proteins.

DNA 由多種不同的蛋白質 來照料和維護。

DNA is wound around proteins called histones,

DNA 被組織蛋白所纏繞，

which enable cells to pack large amounts of DNA into our nucleus.

組織蛋白讓細胞能夠把 大量 DNA 裝入我們的細胞核中。

These machines are called chromatin remodelers,

這些機械叫做染色質重塑蛋白，

and the way they work is that they basically scoot the DNA

基本上，它們做的是快速將 DNA 送到這些組織蛋白周圍，

around these histones

and they allow new pieces of DNA to become exposed.

且它們會讓 DNA 的 新片段暴露出來。

This DNA can then be recognized by other machinery.

接著，此 DNA 就會 被其他機器辨認出來。

In this case, this large molecular machine

在這個例子中，此大型分子機械

is looking for a segment of DNA

在尋找基因起始的那個 DNA 節段。

that tells it it's at the beginning of a gene.

Once it finds a segment,

一旦它找到了這個節段，

it basically undergoes a series of shape changes

基本上，它就會進行一連串變形，

which enables it to bring in other machinery

讓它能夠帶入其他機器，

that in turn allows a gene to get turned on or transcribed.

而那些機器就會讓 基因被活化或轉錄。

This has to be a very tightly regulated process,

這個過程必須要非常嚴謹地控管，

because turning on the wrong gene at the wrong time

因為若在錯的時間把錯的基因活化，

can have disastrous consequences.

可能會造成災難性的後果。

Scientists are now able to use protein machines

現在，科學家能用 蛋白質機械來編輯基因組。

to edit genomes.

I'm sure all of you have heard of CRISPR.

我相信大家都聽過 CRISPR。

CRISPR takes advantage of a protein known as Cas9,

CRISPR 就利用了 叫做 Cas9 的蛋白質，

which can be engineered to recognize and cut

將它編輯之後就可以辨認和切斷

a very specific sequence of DNA.

非常特定的 DNA 序列。

In this example,

在這個例子中， 用了兩個 Cas9 蛋白質

two Cas9 proteins are being used to excise a problematic piece of DNA.

來切除一段有問題的 DNA。

For example, a part of a gene that may give rise to a disease.

比如，基因的某部分 可能會造成某種疾病。

Cellular machinery is then used

接著，使用細胞機器，

to basically glue two ends of the DNA back together.

將 DNA 的兩端重新黏合起來。

As a molecular animator,

身為分子動畫師， 我最大的挑戰之一是

one of my biggest challenges is visualizing uncertainty.

將不確定性給具象化。

All of the animations I've shown to you represent hypotheses,

我剛才給各位看的 所有動畫都只是假設，

how my collaborators think a process works,

我的合作夥伴根據 他們手中的最佳資訊，

based on the best information that they have.

來判定其運作過程，

But for a lot of molecular processes,

但，對大多數分子的運作過程，

we're still really at the early stages of understanding things,

我們都還在了解的初期， 還有很多要學。

and there's a lot to learn.

The truth is

事實是，這些看不見的 分子世界非常廣大，

that these invisible molecular worlds are vast and largely unexplored.

且我們只探索了冰山的一角。

To me, these molecular landscapes

對我來說，探索這些分子景色

are just as exciting to explore as a natural world

和探索我們身邊看得見的大自然

that's visible all around us.

一樣讓人興奮。

Thank you.

謝謝。

(Applause)

（掌聲）