評論
打印
Take a look at this drawing. Can you tell what it is?
請看這幅圖。大家知道這是什么嗎？
I'm a molecular biologist by training, and I've seen a lot of these kinds of drawings.
我是一個接受過訓練的分子生物學家，因此我已經看過了很多這類圖片。
They're usually referred to as a model figure, a drawing that shows how we think a cellular or molecular process occurs.
他們通常被稱作模型圖片，展示我們對細胞或分子過程是如何進行的理解。
This particular drawing is of a process called clathrin-mediated endocytosis.
這幅圖描述的是這樣一個過程，它叫網格蛋白介質的內吞。
It's a process by which a molecule can get from the outside of the cell to the inside
該過程是指一個分子可以從細胞外轉運入細胞內，
by getting captured in a bubble or a vesicle that then gets internalized by the cell.
轉入的方式是通過先被捕捉進小泡或囊中，隨后被細胞內在化。
There's a problem with this drawing, though, and it's mainly in what it doesn't show.
但這幅圖有一個問題，這個問題主要是這幅圖所沒有表現的東西。
From lots of experiments, from lots of different scientists,
從大量的實驗中，從大量不同的科學家身上，
we know a lot about what these molecules look like, how they move around in the cell,
我們對這些分子的樣子，它們是如何在細胞內移動的了解很多，
and that this is all taking place in an incredibly dynamic environment.
這些都發生在一個不可思議的動態的環境中。
So in collaboration with a clathrin expert Tomas Kirchhausen,
因此，在與網格蛋白專家托馬斯·科切豪斯合作中，
we decided to create a new kind of model figure that showed all of that.
我們決定創造一個新的模型圖片，它可以展示所有的細節。
So we start outside of the cell. Now we're looking inside.
于是我們從細胞外開始。現在，我們看到的是內部。
Clathrin are these three-legged molecules that can self-assemble into soccer-ball-like shapes.
網格蛋白就是那些三條腿的分子，它們可以自己組合成足球的形狀。
Through connections with a membrane,
通過膜的相互連接，
clathrin is able to deform the membrane and form this sort of a cup that forms this sort of a bubble, or a vesicle,
網格蛋白可以使膜發生變形，然后形成這種像杯子一樣的形狀，接著形成這種像小泡或小囊樣的形狀，
that's now capturing some of the proteins that were outside of the cell.
現在它正在捕捉一些細胞外的蛋白質。
Proteins are coming in now that basically pinch off this vesicle, making it separate from the rest of the membrane,
蛋白質正在進入，基本上掐斷了小囊，使得它從膜上分離開來，
and now clathrin is basically done with its job, and so proteins are coming in now
現在，網格蛋白基本上已經完成了它的使命，于是，蛋白質就進來了，
we've covered them yellow and orange -- that are responsible for taking apart this clathrin cage.
我們用黃色和橙色來標記它們，它們負責將網格蛋白形成的籠子拆開。
And so all of these proteins can get basically recycled and used all over again.
于是所有這些蛋白質基本上都可以循環，重新加以利用。
