Michael Levin: The electrical blueprints that orchestrate life | TED

507,144 views ・ 2021-03-31

TED


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翻译人员: Hancheng Li 校对人员: Helen Chang
00:12
Chris Anderson: Mike, welcome.
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克里斯·安德森:迈克,欢迎你。
00:14
It's good to see you. I'm excited for this conversation.
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很高兴见到你。 我很期待接下来的讨论。
00:16
Michael Levin: Thank you so much. I'm so happy to be here.
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迈克尔·列文:非常感谢。 我也很高兴来到这里。
安德森:大多数人脑海里 对生物学有这样的概念模型,
00:19
CA: So, most of us have this mental model in biology
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00:22
that DNA is a property of every living thing,
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就是DNA是所有生物的一种属性,
00:27
that it is kind of the software that builds the hardware of our body.
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它好像电脑软件一样, 指引我们搭建出身体这个硬件。
00:32
That's how a lot of us think about this.
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很多人都是这样想的。
00:34
That model leaves too many deep mysteries.
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这种模型引出了很多很深的谜团。
00:37
Can you share with us some of those mysteries
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你可以向我们分享这些谜团吗?
00:40
and also what tadpoles have to do with it?
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顺便提一提它们与小蝌蚪之间的关系。
00:44
ML: Sure. Yeah.
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列文:当然,没问题。
00:45
I'd like to give you another perspective on this problem.
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我想分享的是这个问题的另一个角度。
00:48
One of the things that DNA does is specify the hardware of each cell.
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DNA的一个功能是 指定每个细胞所含的硬件。
00:52
So the DNA tells every cell what proteins it's supposed to have.
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所以DNA告诉每个细胞, 它们应该含有哪些蛋白质。
00:57
And so when you have tadpoles, for example,
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比如我们研究蝌蚪,
01:00
you see the kind of thing
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你会发现这种现象,
01:02
that most people think is sort of a progressive unrolling of the genome.
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大多数人会觉得是 基因组的“阶段性展开”。
01:07
Specific genes turn on and off,
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特定的基因会激活或者休眠,
01:09
and a tadpole, as it becomes a frog,
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当蝌蚪发育成青蛙时,
01:11
has to rearrange its face.
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它会重新组合脸部器官。
01:12
So the eyes, the nostrils, the jaws -- everything has to move.
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比如眼睛、鼻孔、下巴, 各种东西都移动了。
01:15
And one way to think about it used to be that, well,
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过去解读这种现象的一种方式是
01:18
you have a sort of hardwired set of movements
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你有一系列固定的移动路线,
01:20
where all of these things move around and then you get your frog.
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这些器官按照给定路线移动, 于是就形成了青蛙。
01:24
But actually, a few years ago, we found a pretty amazing phenomenon,
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但事实上,就几年前, 我们发现了一个很了不起的现象,
01:27
which is that if you make so-called "Picasso frogs" --
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就是当我们研究所谓的 “毕加索青蛙”——
01:30
these are tadpoles where the jaws might be off to the side,
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这指的是一些蝌蚪比如说下巴长歪了,
01:33
the eyes are up here, the nostrils are moved,
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眼睛跑到顶上,鼻孔也长偏了,
01:35
so everything is shifted --
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总之各种东西位置不对——
01:37
these tadpoles make largely normal frog faces.
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这些蝌蚪依然能发育出 大致正常的蛙脸。
01:40
Now, this is amazing,
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那么这就很厉害了,
因为所有器官的起始位置都不正常,
01:42
because all of the organs start off in abnormal positions,
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01:45
and yet they still end up making a pretty good frog face.
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然而最后还能长成比较正常的蛙脸。
01:48
And so what it turns out is that this system,
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所以我们发觉这样一个系统,
01:50
like many living systems,
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很像其他的生物系统,
01:52
is not a hardwired set of movements,
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它不是一系列固定的路线,
01:54
but actually works to reduce the error between what's going on now
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而是可以努力降低从当前状态
01:58
and what it knows is a correct frog face configuration.
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发展到它所知的正确蛙脸状态的误差。
02:02
This kind of decision-making
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这种决策能力
02:03
that involves flexible responses to new circumstances,
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涉及到如何灵活应对各种新情况,
02:07
in other contexts, we would call this intelligence.
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放在其他领域, 我们会称之为智能、智慧。
02:10
And so what we need to understand now is not only the mechanisms
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那么我们需要理解的就不只是
这些细胞移动的机制,
02:14
by which these cells execute their movements
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02:16
and gene expression and so on,
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或者基因表达之类的,
02:18
but we really have to understand the information flow:
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我们更要理解信息在其中的流向:
02:21
How do these cells cooperate with each other
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这些细胞如何互相沟通
02:23
to build something large and to stop building
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以构建大规模机体,
并且在构建完成时 知道应该停止构建。
02:26
when that specific structure is created?
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02:29
And these kinds of computations, not just the mechanisms,
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这种运算过程,不仅是机制,
02:32
but the computations of anatomical control,
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而是解剖学控制的精密计算,
02:35
are the future of biology.
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是生物学未来的研究方向。
02:37
CA: And so I guess the traditional model
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安德森:那么我感觉传统的模型是说
02:39
is that somehow cells are sending biochemical signals to each other
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细胞之间会互相传递生物化学信号
02:43
that allow that development to happen the smart way.
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使得生物体发育能够 灵活、有智能地进行。
02:48
But you think there is something else at work.
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不过你认为还有其它的机制在起作用。
02:50
What is that?
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那是什么呢?
02:51
ML: Well, cells certainly do communicate biochemically and via physical forces,
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列文:细胞肯定会通过生物化学信号 以及物理力的作用进行沟通,
但还有另外一个机制是非常有趣的,
02:55
but there's something else going on that's extremely interesting,
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它叫做生物电,
02:58
and it's basically called bioelectricity,
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03:02
non-neural bioelectricity.
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而且是非神经传导的生物电。
03:04
So it turns out that all cells --
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其实所有的细胞——
03:05
not just nerves, but all cells in your body --
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不只是神经细胞,而是全身所有的细胞——
03:07
communicate with each other using electrical signals.
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都用电信号来进行相互交流。
03:10
And what you're seeing here is a time-lapse video.
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这里看到的是一段延时摄影片段。
03:12
For the first time,
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历史上第一次,
03:14
we are now able to eavesdrop on all of the electrical conversations
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我们能够窃听细胞与细胞之间
03:17
that the cells are having with each other.
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用电信号进行的所有对话。
03:19
So think about this.
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所以想想看。
03:20
We're now watching --
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我们现在看到的——
03:22
This is an early frog embryo.
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这是青蛙的一个早期胚胎。
03:23
This is about eight hours to 10 hours of development.
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这大概是发育的前 8 到 10 小时。
03:26
And the colors are showing you actual electrical states
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这里的颜色代表着实际的电位,
03:30
that allow you to see all of the electrical software
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这让我们看到所有的电流“软件”,
03:33
that's running on the genome-defined cellular hardware.
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在由基因组所定义的细胞“硬件”上 执行的样子。
03:36
And so these cells are basically communicating with each other
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简单来说,这些细胞就在互相沟通:
03:40
who is going to be head, who is going to be tail,
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哪些应该形成头部, 哪些应该形成尾部,
03:43
who is going to be left and right and make eyes and brain and so on.
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哪些去左边、去右边, 哪些应该形成眼睛、大脑等等。
03:46
And so it is this software
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其实是这种软件
03:47
that allows these living systems to achieve specific goals,
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使得生物体去实现特定的目标,
03:51
goals such as building an embryo
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比如搭建一个胚胎,
03:53
or regenerating a limb for animals that do this,
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或者是有再生能力的动物 修复损伤的肢体,
03:56
and the ability to see these electrical conversations
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我们有能力观察到这些电信号对话,
04:02
gives us some really remarkable opportunities
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这给了我们一些重大机会,
04:05
to target or to rewrite the goals towards which
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让我们引导甚至是重写生物体
04:08
these living systems are operating.
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想要达到的各种目标。
04:10
CA: OK, so this is pretty radical.
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安德森:好的,听起来太厉害了。
04:12
Let me see if I understand this.
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你看看我理解的对不对。
04:14
What you're saying is that when an organism starts to develop,
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你说的是,当有机体开始发育的时候,
04:18
as soon as a cell divides,
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每当一个细胞分裂时,
04:19
electrical signals are shared between them.
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电信号都在细胞之间传递。
04:23
But as you get to, what, a hundred, a few hundred cells,
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但当你发展到一百个、 几百个细胞级别时,
04:27
that somehow these signals end up forming essentially like a computer program,
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这些信号就不知怎么 变成像电脑程序一样,
这个程序就包含了 有机体所需的所有信息,
04:34
a program that somehow includes all the information needed
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04:39
to tell that organism
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告诉这个有机体
04:41
what its destiny is?
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发展的结局是什么?
04:43
Is that the right way to think about it?
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你觉得我理解的对吗?
04:45
ML: Yes, quite.
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列文:对的,差不多。
04:46
Basically, what happens is that these cells,
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简单解释就是这些细胞
04:48
by forming electrical networks much like networks in the brain,
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通过组成电信号网络, 很像大脑里的神经,
04:52
they form electrical networks,
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它们组成这种网络,
04:54
and these networks process information including pattern memories.
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然后这些网络可以处理信息 并记忆一些模板。
04:58
They include representation of large-scale anatomical structures
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这些模板包含了 大规模解剖学结构的蓝图,
05:03
where various organs will go,
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比如各种器官该长在哪里,
05:05
what the different axes of the animal -- front and back, head and tail --
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各种动物的方向性—— 哪里是前是后,哪里是头是尾——
05:08
are going to be,
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应该怎么安排,
05:10
and these are literally held in the electrical circuits
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这些信息就储存在电路中,
05:12
across large tissues
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横跨大块的组织,
05:14
in the same way that brains hold other kinds of memories and learning.
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与大脑储存各种信息、 学习知识的方式一样。
05:20
CA: So is this the right way to think about it?
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安德森:所以这种理解是对的吗?
05:22
Because this seems to be such a big shift.
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因为我感觉这种转变很大。
05:24
I mean, when I first got a computer,
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我指的是,当我有了 自己的第一台电脑时,
05:27
I was in awe of the people who could do so-called "machine code,"
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我特别佩服一些程序员 可以写所谓“机器语言”,
05:32
like the direct programming of individual bits in the computer.
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就是直接去操纵电脑的每一个字节。
05:36
That was impossible for most mortals.
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大多数人是不可能做到的。
05:38
To have a chance of controlling that computer,
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如果想要操控那台电脑,
你必须要会这种编程语言,
05:40
you'd have to program in a language,
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05:42
which was a vastly simpler way of making big-picture things happen.
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用最底层、最简洁的方式 去实现大规模的复杂功能。
05:49
And if I understand you right,
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如果我理解得对,
05:51
what you're saying is that most of biology today has sort of taken place
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你所描述的就是现阶段的生物学
05:54
trying to do the equivalent of machine code programming,
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就在努力实现用类似 “机器代码”的方式编程,
05:57
of understanding the biochemical signals between individual cells,
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尝试理解各个细胞之间的 生物化学信号,
06:00
when, wait a sec, holy crap, there's this language going on,
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但突然,我的天啊, 出现了这么个新语言,
06:03
this electrical language, which, if you could understand that,
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这个生物电的语言, 如果你们能研究明白的话,
06:08
that would give us a completely different set of insights
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会让我们站在完全不一样的视角,
06:11
into how organisms are developing.
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去理解生物体的发育发展。
06:13
Is that metaphor basically right?
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这个类比你觉得对吗?
06:15
ML: Yeah, this is exactly right.
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列文:对的,完全正确。
06:17
So if you think about the way programming was done in the '40s,
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回想1940年代,大家是怎么编程的,
06:20
in order to get your computer to do something different,
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如果你想让电脑实现不同功能,
那就得手动插拔各种电线。
06:23
you would physically have to shift the wires around.
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你得钻进机箱里去 重接电脑硬件的连线。
06:25
So you'd have to go in there and rewire the hardware.
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你要这样直接操纵硬件,
06:28
You'd have to interact with the hardware directly,
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06:30
and all of your strategies for manipulating that machine
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而且所有控制电脑的方式
06:33
would be at the level of the hardware.
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都是在硬件级别的。
06:35
And the reason we have this now amazing technology revolution,
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我们现在有如此惊人的技术革新,
06:38
information sciences and so on,
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尤其信息科学相关领域,
06:40
is because computer science moved from a focus on the hardware
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就是因为计算机科学不只是关注硬件,
06:43
on to understanding that if your hardware is good enough --
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而是在硬件足够好的条件下, 转为关注——
06:46
and I'm going to tell you that biological hardware is absolutely good enough --
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这里插一句话, 生物体的硬件绝对是足够好的——
06:50
then you can interact with your system not by tweaking or rewiring the hardware,
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你与系统的互动方式, 不通过调整或重新布线硬件,
06:56
but actually, you can take a step back and give it stimuli or inputs
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而是可以退一步, 给系统加入某种刺激或输入,
06:59
the way that you would give to a reprogrammable computer
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就好像你给可编程的电脑 输入信息一样,
07:02
and cause the cellular network to do something completely different
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这样使得整个细胞网络去实现
没有外界刺激情况下不会去做的任务。
07:07
than it would otherwise have done.
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07:09
So the ability to see these bioelectrical signals
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因此我们能够观察到生物电信号
07:12
is giving us an entry point directly into the software
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给我们一个入口,
给我们一个直接进入 指导大规模解剖的软件的入口,
07:15
that guides large-scale anatomy,
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07:17
which is a very different approach to medicine
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是很不一样趋近医学的方式,
07:21
than to rewiring specific pathways inside of every cell.
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与重新连接每个细胞的方式大不相同。
07:25
CA: And so in many ways, this is the amazingness of your work
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安德森:所以说从各个角度看, 这就是你们科研成果很了不起之处,
07:27
is that you're starting to crack the code of these electrical signals,
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是你们开始破译这种电信号的密码,
07:31
and you've got an amazing demonstration of this
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你有一个很神奇的例子
07:33
in these flatworms.
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是关于扁虫的。
07:35
Tell us what's going on here.
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请给我们解释一下。
07:37
ML: So this is a creature known as a planarian.
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列文:这种生物名叫涡虫。
07:40
They're flatworms.
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它属于扁形动物门。
07:41
They're actually quite a complex creature.
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它们其实结构很复杂。
07:43
They have a true brain, lots of different organs and so on.
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它们有完整的大脑, 有各种不同的器官。
07:46
And the amazing thing about these planaria
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这些涡虫厉害的地方在于
07:48
is that they are highly, highly regenerative.
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它们的再生能力极强。
07:50
So if you cut it into pieces -- in fact, over 200 pieces --
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所以如果你把它切成小段—— 事实上,超过200个小段——
07:54
every piece will rebuild exactly what's needed
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每一段都可以再生出 其所需的一切部件,
07:58
to make a perfect little worm.
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恢复成完整的小虫。
08:00
So think about that.
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大家揣摩揣摩。
08:01
This is a system where every single piece
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这个系统里的每一小块,
08:03
knows exactly what a correct planarian looks like
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都清楚地知道 一只正常的涡虫长什么样,
08:06
and builds the right organs in the right places and then stops.
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把所有需要的器官 长在正确的位置,然后停止生长。
08:09
And that's one of the most amazing things about regeneration.
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这是生物再生最了不起的事情之一。
08:12
So what we discovered is that if you cut it into three pieces
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我们发现一个现象, 就是如果你把它切成三段,
08:15
and amputate the head and the tail and you just take this middle fragment,
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就是把头部和尾部切除, 只留下中间那段,
08:19
which is what you see here,
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就是画面中看到的,
08:20
amazingly, there is an electrical gradient, head to tail, that's generated
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神奇的现象是,虫的头部到尾部 展现出生物电位的梯度,
08:24
that tells the piece where the heads and the tails go
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告诉这一小段身体头部和尾部 应该长在哪里,
08:27
and in fact, how many heads or tails you're supposed to have.
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其实还表示了应该长出 几个头和几条尾巴。
08:30
So what we learned to do is to manipulate this electrical gradient,
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所以我们就想到去改变这个电位梯度,
08:34
and the important thing is that we don't apply electricity.
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然而重要的是我们并不直接输入电流。
08:37
What we do instead was we turned on and off the little transistors --
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我们做的实际是把细胞上的 小电容器打开或关闭——
08:41
they're actual ion channel proteins --
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其实是用作离子通道的蛋白质——
08:44
that every cell natively uses to set up this electrical state.
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细胞原本就利用这些蛋白质 来调控电位状态。
08:47
So now we have ways to turn them on and off,
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于是我们就有办法开关这些电容器,
08:49
and when you do this, one of the things you can do
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如此调整的话,可以做的事情是
08:52
is you can shift that circuit to a state that says no, build two heads,
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你把细胞电路调到一个状态, 让他发育出两个头来,
08:56
or in fact, build no heads.
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或者是一个头也不发育。
画面看到的就是真实的涡虫, 有两个头的,也有无头的,
08:58
And what you're seeing here are real worms that have either two or no heads
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09:02
that result from this,
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就是这么调整得来的,
09:03
because that electrical map is what the cells are using
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因为细胞就是用那个电位图来
09:06
to decide what to do.
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决定怎么生长的。
09:08
And so what you're seeing here are live two-headed worms.
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这里所看到的就是活的双头涡虫。
09:11
And, having generated these, we did a completely crazy experiment.
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发育了这些涡虫之后, 我们又做了另一个疯狂的实验。
09:15
You take one of these two-headed worms, and you chop off both heads,
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就是你切除一只双头涡虫的两个头,
09:19
and you leave just the normal middle fragment.
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只留下中间的那一段。
09:21
Now keep in mind, these animals have not been genomically edited.
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提醒一下,我们从未编辑过 这些动物的基因。
09:24
There's absolutely nothing different about their genomes.
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它们的基因组与自然的涡虫没有差别。
09:27
Their genome sequence is completely wild type.
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它们的基因组序列就是野生型的。
09:30
So you amputate the heads, you've got a nice normal fragment,
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所以如果你切除两个头, 获得了一段正常的中间段,
09:34
and then you ask: In plain water, what is it going to do?
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然后你就想问: 在清水里它会怎样再生?
09:37
And, of course, the standard paradigm would say,
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如果按照传统惯例,你肯定会说
09:39
well, if you've gotten rid of this ectopic extra tissue,
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既然我们移除了这段异位的组织,
09:42
the genome is not edited so it should make a perfectly normal worm.
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然后基因组也没改变, 它应该会长成完全正常的涡虫。
09:46
And the amazing thing is that it is not what happens.
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然而了不起的是,结果并不是这样的。
09:49
These worms, when cut again and again, in the future, in plain water,
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这些虫子不论切多少次, 之后在清水里
09:55
they continue to regenerate as two-headed.
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它们依然会再生成双头的涡虫。
09:57
Think about this.
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大家想想看。
09:58
The pattern memory to which these animals will regenerate after damage
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这些动物受到损伤后再生的模板
10:04
has been permanently rewritten.
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已经被永久改写了。
10:06
And in fact, we can now write it back and send them back to being one-headed
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事实上,我们也可以把它改写回原状, 让它们变回一个头,
10:09
without any genomic editing.
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这都无需经过基因剪辑。
10:11
So this right here is telling you that the information structure
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通过这个现象,大家就知道
涡虫应该长出多少个头的信息架构
10:14
that tells these worms how many heads they're supposed to have
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10:17
is not directly in the genome.
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并不直接储存在基因组里。
10:19
It is in this additional bioelectric layer.
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它其实储存在这个额外的生物电层。
10:21
Probably many other things are as well.
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可能很多其他信息也是这样。
10:23
And we now have the ability to rewrite it.
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而且我们现在有能力改写它了。
10:25
And that, of course, is the key definition of memory.
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而这其实就是“记忆”的关键标准。
10:29
It has to be stable, long-term stable, and it has to be rewritable.
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它必须是稳定的,长久稳定的, 而且可被覆写的。
10:33
And we are now beginning to crack this morphogenetic code
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我们逐渐学会破解 这种生物发育的密码,
10:36
to ask how is it that these tissues store a map of what to do
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慢慢理解这些组织 如何储存发育指令的信息,
10:41
and how we can go in and rewrite that map to new outcomes.
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以及我们如何能够改写这些信息, 引导出全新的结果。
10:46
CA: I mean, that seems incredibly compelling evidence
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安德森:我觉得 这是非常有信服力的证据,
10:50
that DNA is just not controlling the actual final shape
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说明DNA并不是真正控制这些生物体
10:57
of these organisms,
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最终形态的,
10:59
that there's this whole other thing going on,
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实际上还有这个完全独立的作用,
11:02
and, boy, if you could crack that code,
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天啊,如果你们可以破解的话
11:04
what else could that lead to.
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想想可以实现什么。
11:06
By the way, just looking at these ones.
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哦对了,我看这些虫子。
11:08
What is life like for a two-headed flatworm?
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这种双头的涡虫是怎样生活的呢?
11:11
I mean, it seems like it's kind of a trade-off.
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我感觉看起来像是有利有弊。
11:13
The good news is you have this amazing three-dimensional view of the world,
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好的一面是能用三维的方式观察世界,
11:17
but the bad news is you have to poop through both of your mouths?
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坏的一面大概是 要从两个头的嘴里排泄?
11:22
ML: So, the worms have these little tubes called pharynxes,
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列文:这些虫子长有这些小管子 叫做咽管,
11:26
and the tubes are sort of in the middle of the body,
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这些管子长在身体中间,
11:29
and they excrete through that.
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它们会从咽管排遗。
11:30
These animals are perfectly viable.
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这些动物完全可以生存。
11:32
They're completely happy, I think.
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我觉得它们也挺开心吧。
11:35
The problem, however,
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但有个问题是
11:36
is that the two heads don't cooperate all that well,
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它们的两个头配合得不是很好,
11:39
and so they don't really eat very well.
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所以它们吃东西有一定困难。
11:41
But if you manage to feed them by hand,
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如果你自己动手去喂它们的话,
11:43
they will go on forever,
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它们就可以一直活下去,
11:44
and in fact, you should know these worms are basically immortal.
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其实你可能想象到, 这些虫子基本上是永生的。
11:47
So these worms, because they are so highly regenerative,
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这些虫子因为具有极强的再生能力,
11:50
they have no age limit,
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它们就没有年龄限制,
11:52
and they're telling us that if we crack this secret of regeneration,
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然后它们告诉我们, 如果能破解再生的秘密,
11:55
which is not only growing new cells but knowing when to stop --
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这指的不仅是长出新细胞, 而且也指知道如何停止——
11:58
you see, this is absolutely crucial --
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这一点其实非常重要——
12:00
if you can continue to exert this really profound control
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如果可以不断通过细胞
对生物的三维结构加以精密的控制,
12:04
over the three-dimensional structures that the cells are working towards,
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12:08
you could defeat aging as well as traumatic injury
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你就可以击败衰老或是严重的创伤,
12:11
and things like this.
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以及类似的损伤。
12:12
So one thing to keep in mind is that this ability to rewrite
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我们要记住的一点是,
这种改写身体大规模解剖结构的能力
12:15
the large-scale anatomical structure of the body
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12:18
is not just a weird planarian trick.
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并不只是涡虫身上的小把戏。
12:20
It's not just something that works in flatworms.
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不是说只能在扁虫上才起作用。
12:23
What you're seeing here is a tadpole with an eye and a gut,
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这里所看到的蝌蚪肠子上长了一个眼睛,
12:26
and what we've done is turned on a very specific ion channel.
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我们所做的就是 打开了一个特定的离子通道。
12:31
So we basically just manipulated these little electrical transistors
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简单来说,我们就是调整了细胞里的
12:34
that are inside of cells,
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那些小电容器,
12:36
and we've imposed a state on some of these gut cells
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我们把肠子上的某些细胞 调整为特定的电位,
12:39
that's normally associated with building an eye.
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而这种电位一般和眼睛的生长有关。
12:42
And as a result, what the cells do is they build an eye.
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于是细胞所做的就是搭建了一个眼睛。
12:45
These eyes are complete.
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这些眼睛都结构完整。
12:46
They have optic nerve, lens, retina,
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它们有视神经、晶状体、角膜,
12:50
all the same stuff that an eye is supposed to have.
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正常眼球所有的一切它都有。
12:52
They can see, by the way, out of these eyes.
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而且这些眼睛都是有视觉的。
12:54
And what you're seeing here
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你在这里看到的
12:55
is that by triggering eye-building subroutines
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就是我们通过调整蝌蚪的生理软件,
12:58
in the physiological software of the body,
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触发了搭建眼睛的“子程序”,
13:01
you can very easily tell it to build a complex organ.
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你可以很容易的让生物 搭建出复杂的器官。
13:04
And this is important for our biomedicine,
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这对生物医学是非常关键的,
13:06
because we don't know how to micromanage the construction of an eye.
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因为我们还不知道 如何一步搭建出一个眼睛。
13:10
I think it's going to be a really long time
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我觉得我们需要很长时间
13:12
before we can really bottom-up build things like eyes or hands and so on.
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才能搞清楚如何从无到有 组建出眼睛、手之类的器官。
13:17
But we don't need to, because the body already knows how to do it,
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但我们并不需要知道, 因为我们的身体自然就知道如何搭建,
13:20
and there are these subroutines that can be triggered
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而且也有这些可以手动激活的子程序,
13:23
by specific electrical patterns that we can find.
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通过我们观察到的电位图来激活。
13:26
And this is what we call "cracking the bioelectric code."
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这就是我们所说的“破解生物电的密码”。
13:29
We can make eyes. We can make extra limbs.
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我们可以造出眼睛,造出肢体。
13:31
Here's one of our five-legged tadpoles.
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这是我们培养出的五条腿的蝌蚪。
13:33
We can make extra hearts.
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我们可以造出好几个心脏。
13:35
We're starting to crack the code to understand where are the subroutines
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我们开始破解密码,逐渐理解
这个软件里的子程序都在哪里,
13:39
in this software
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13:40
that we can trigger and build these complex organs
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可以让我们触发并组建出复杂器官,
13:43
long before we actually know how to micromanage the process
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远早于我们真正学会一步步
从细胞级别开始组建。
13:46
at the cellular level.
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13:47
CA: So as you've started to get to learn this electrical layer
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安德森:那么你们开始 了解这个生物电层,
13:52
and what it can do,
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以及它的功能,
13:53
you've been able to create --
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你们就可以创造——
13:56
is it fair to say it's almost like a new, a novel life-form,
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一种全新的生物形态,可以这么说吗?
14:00
called a xenobot?
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叫做“活体机器人”?
14:01
Talk to me about xenobots.
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请给我介绍一下活体机器人。
14:03
ML: Right.
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列文:好的。
14:04
So if you think about this, this leads to a really strange prediction.
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你想想看,这引出了一种 非常奇怪的预测。
14:08
If the cells are really willing to build towards a specific map,
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如果细胞倾向于往某种蓝图去搭建,
14:12
we could take genetically unaltered cells,
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我们就可以分离出 未经过基因编辑的细胞,
14:16
and what you're seeing here is cells taken out of a frog body.
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这里看到的就是从青蛙体内取出的细胞。
14:19
They've coalesced in a way that asks them to re-envision their multicellularity.
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它们聚集在一起的样子 似乎像是在预想出多细胞的状态。
14:24
And what you see here
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画面中所看到的
14:25
is that when liberated from the rest of the body of the animal,
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就是当细胞从动物体分离出来之后,
14:28
they make these tiny little novel bodies that are, in terms of behavior,
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它们聚集成这些微小的新结构体, 从它们的行为来说,
14:32
you can see they can move, they can run a maze.
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这里看到它们会移动、会走迷宫。
14:35
They are completely different from frogs or tadpoles.
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这些结构体与青蛙或蝌蚪完全不一样。
14:38
Frog cells, when asked to re-envision what kind of body they want to make,
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当我们让青蛙细胞 这样预想出身体构建的蓝图,
14:44
do something incredibly interesting.
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它们就会做神奇的事情。
14:46
They use the hardware that their genetics gives them,
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它们用基因所赋予的硬件,
14:51
for example, these little hairs, these little cilia
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比如这些细小的毛发,
14:54
that are normally used to redistribute mucus on the outside of a frog,
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原本是拿来分配青蛙表皮的粘液的,
14:58
those are genetically specified.
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这些是基因所定义好的。
14:59
But what these creatures did,
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这些小生物所做的,
15:02
because the cells are able to form novel kinds of bodies,
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因为这些细胞可以聚集形成新的机体,
15:06
they have figured out how to use these little cilia
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它们就发觉如何利用这些小毛发
15:09
to instead row against the water, and now have locomotion.
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在水里划动,于是就有了运动能力。
15:13
So not only can they move around, but they can, and here what you're seeing,
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所以它们不仅能到处移动, 还可以像图中看到的,
15:18
is that these cells are coalescing together.
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它们会自动聚集在一起。
15:21
Now they're starting to have conversations about what they are going to do.
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它们现在在互相交流, 讨论接下来要做什么。
15:24
You can see here the flashes are these exchanges of information.
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你们可以看到这些小闪光 就是信息的交换。
15:28
Keep in mind, this is just skin.
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提醒一下,这只是皮肤细胞而已。
15:30
There is no nervous system. There is no brain. This is just skin.
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没有神经系统,没有大脑。 只是皮肤细胞。
15:34
This is skin that has learned to make a new body
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光皮肤细胞就知道 如何聚集形成新机体,
15:37
and to explore its environment and move around.
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并且如何移动、探索周围的环境。
15:40
And they have spontaneous behaviors.
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它们也展现出一些自发行为。
15:42
You can see here where it's swimming down this maze.
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比如这里可以看到它们在迷宫里游动。
15:45
At this point, it decides to turn around and go back where it came from.
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走到这里,它又决定调头往反方向走。
15:48
So it has its own behavior, and this is a remarkable model system
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它们有自己的行为, 而这就是一个非常厉害的模型系统,
15:52
for several reasons.
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原因有以下几个。
15:53
First of all, it shows us the amazing plasticity of cells
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首先,它告诉我们野生型的细胞
15:57
that are genetically wild type.
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也有很了不起的可塑性。
15:58
There is no genetic editing here.
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我们没有编辑过基因。
16:00
These are cells that are really prone to making some sort of functional body.
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这些细胞能很容易组建出 具有特定功能的结构体。
16:05
The second thing,
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第二点是,
16:06
and this was done in collaboration with Josh Bongard's lab at UVM,
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这是我们和佛蒙特大学 约什·邦嘉德教授实验室合作的成果,
16:10
they modeled the structure of these things and evolved it in a virtual world.
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他们把这些生物的结构建模, 放在虚拟环境里使其演化。
16:16
So this is literally -- on a computer, they modeled it on a computer.
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这个就确实是——在电脑里了, 是他们做的计算机模拟。
16:19
So this is literally the only organism that I know of on the face of this planet
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这确实是我所知的, 地球上唯一的有机体,
16:23
whose evolution took place not in the biosphere of the earth
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它的进化不是在地球生物圈中进行的,
16:27
but inside a computer.
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而是在电脑程序里进行的。
16:29
So the individual cells have an evolutionary history,
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这里每一个细胞都有自己的进化史,
16:31
but this organism has never existed before.
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但是这个有机体从未真实存在过。
16:34
It was evolved in this virtual world,
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它是在虚拟世界里演化的,
16:36
and then we went ahead and made it in the lab,
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然后我们再在实验室里把它们造出来,
16:39
and you can see this amazing plasticity.
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你也可以观察到很强的可塑性。
16:41
This is not only for making useful machines.
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这不只是说生产出有用的活体机械。
16:45
You can imagine now programming these to go out into the environment
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你可以想象,如果我们把这些细胞 编程并放到环境里,
16:49
and collect toxins and cleanup,
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它们可以收集毒素、做清扫,
16:50
or you could imagine ones made out of human cells
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或者也可以想象人体细胞造出的机械
16:53
that would go through your body and collect cancer cells
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会在身体里游走并清理癌细胞,
16:56
or reshape arthritic joints,
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或是重组关节炎患者的关节,
16:58
deliver pro-regenerative compounds,
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传递促进再生的化合物,
17:01
all kinds of things.
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各种各样的事情。
17:02
But not only these useful applications -- this is an amazing sandbox
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但它不止有这些应用—— 它还是一个很了不起的试验场,
17:05
for learning to communicate morphogenetic signals to cell collectives.
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让我们学习用生物发育的信号 与细胞组织对话。
17:10
So once we crack this, once we understand how these cells decide what to do,
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一旦我们破解了,一旦我们理解 这些细胞如何决定做什么事,
17:15
and then we're going to, of course, learn to rewrite that information,
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之后我们肯定就会学着 去改写这些信息,
17:18
the next steps are great improvements in regenerative medicine,
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那么下一步就是再生医学的突破,
17:23
because we will then be able to tell cells to build healthy organs.
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因为我们可以让细胞 直接造出健康的器官。
17:27
And so this is now a really critical opportunity
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这是目前一个非常重要的机遇,
17:30
to learn to communicate with cell groups,
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去学习与细胞组织交流,
17:32
not to micromanage them, not to force the hardware,
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不是对他们微管理, 也不是强行改变硬件,
17:35
to communicate and rewrite the goals that these cells are trying to accomplish.
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而是交流、改写细胞所想实现的目标。
17:40
CA: Well, it's mind-boggling stuff.
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安德森:好的,听起来太惊人了。
17:42
Finally, Mike, give us just one other story
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最后,迈克,请你分享最后一个故事,
17:45
about medicine that might be to come
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是关于未来可能出现的医药,
17:48
as you develop this understanding
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随着你们逐渐增进
17:51
of how this bioelectric layer works.
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对这个生物电层的理解。
17:54
ML: Yeah, this is incredibly exciting because, if you think about it,
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列文:好的,这其实非常激动人心, 如果你想想看,
17:58
most of the problems of biomedicine --
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生物医学现在的诸多问题——
18:00
birth defects, degenerative disease, aging, traumatic injury, even cancer --
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比如先天缺陷、退化性疾病、衰老、 重大创伤,乃至癌症——
18:06
all boil down to one thing:
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它们说白了都是一件事:
18:07
cells are not building what you would like them to build.
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细胞没按照你想要的的方式 去组建东西。
18:10
And so if we understood how to communicate with these collectives
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那么如果我们理解 如何与细胞聚集体沟通,
18:14
and really rewrite their target morphologies,
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然后重写它们的发育目标,
18:18
we would be able to normalize tumors,
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我们就可以化解肿瘤,
18:21
we would be able to repair birth defects,
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我们可以修复先天缺陷,
18:23
induce regeneration of limbs and other organs,
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可以促成肢体或其它器官的再生,
18:25
and these are things we have already done in frog models.
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而这些事情都在青蛙模型上实现了。
18:29
And so now the next really exciting step
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那么接下来激动人心的一步
18:31
is to take this into mammalian cells
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就是把这些引入到哺乳动物细胞中,
18:35
and to really turn this into the next generation of regenerative medicine
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真正把它转化为 新一代的再生医学成果,
18:39
where we learn to address all of these biomedical needs
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我们从此学会应对 生物医学的各种需求,
18:43
by communicating with the cell collectives
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通过与细胞团体进行沟通,
18:45
and rewriting their bioelectric pattern memories.
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并重写它们的生物电所记忆的模板。
18:49
And the final thing I'd like to say is that the importance of this field
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最后我想提的一点是这个领域的重要性
18:52
is not only for biomedicine.
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不只停留在生物医学。
18:54
You see, this, as I started out by saying,
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回想我一开始就说到,
18:56
this ability of cells in novel environments
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细胞在各种新环境里
18:59
to build all kinds of things besides what their genome tells them
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除了基因组的指令之外, 还能搭建新东西的能力,
19:03
is an example of intelligence,
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是智能、智慧的体现,
19:05
and biology has been intelligently solving problems
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而且生物学早就开始 很有智慧地解决问题,
19:07
long before brains came on the scene.
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远早于动物大脑的发育、形成。
19:09
And so this is also the beginnings of a new inspiration for machine learning
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这些也可以给机器学习领域 带来全新的启发,
19:14
that mimics the artificial intelligence of body cells, not just brains,
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让算法去模仿这些身体细胞, 而不仅是大脑,
19:19
for applications in computer intelligence.
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开拓计算机智能的全新应用。
19:24
CA: Mike Levin, thank you for your extraordinary work
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安德森:迈克·列文, 感谢你们做出的卓越贡献,
19:27
and for sharing it so compellingly with us.
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也感谢你如此热情洋溢地与我们分享。
19:30
Thank you.
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谢谢你。
19:31
ML: Thank you so much. Thank you, Chris.
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列文:非常感谢。谢谢你,克里斯。
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