来源: The Economist

网址: https://www.economist.com/science-and-technology/two-students-of-the-senses-win-the-nobel-prize-for-medicine/21805250

The 2021 Nobel science prizes Two students of the senses win the Nobel prize for medicine

2021年诺贝尔科学奖 两位感官学学生获诺贝尔医学奖

They found the mechanisms of touch and temperature sensitivity

他们发现了触觉和温度敏感性的机制

THE IDEA that there are five senses goes back at least as far as Aristotle. But it is not quite true. Four of the senses are obvious, not least because each is associated with a particular organ: sight with the eyes, hearing with the ears, taste with the tongue and smell with the nose. But the fifth classical sense, touch, is distributed over the whole surface of the body, albeit that it is particularly concentrated in the fingertips.

有五种感官的想法至少可以追溯到亚里士多德。但事实并非如此。四种感官是显而易见的，尤其是因为每种感官都与一个特定的器官有关：视觉用眼睛，听觉用耳朵，味觉用舌头，嗅觉用鼻子。但是第五种经典感觉，触觉，分布在整个身体表面，尽管它特别集中在指尖。

Touch, moreover, is only one of such distributed senses. Others, perceived consciously, include pain, heat and cold. And modern science has shown there are yet further, unconsciously perceived senses, known collectively as proprioception. These keep track of the position and movement of the body and its parts. This year, the Nobel Assembly of the Karolinska Institute, in Stockholm, which awards the Nobel prize for physiology or medicine, chose to honour the discoverers of the molecular mechanisms of two of these distributed senses—temperature and mechanical stimulation.

此外，触觉只是这种分布式感官中的一种。其他人有意识地感知，包括疼痛、热和冷。现代科学表明，还有更深层次的、无意识感知的感觉，统称为本体感觉。这些跟踪身体及其部位的位置和运动。今年，在斯德哥尔摩举行的诺贝尔生理学或医学奖颁奖典礼上，斯德哥尔摩卡罗林斯卡学院的诺贝尔大会选择表彰这些分布式感觉中两种——温度和机械刺激——的分子机制的发现者。

The winners were David Julius of the University of California, San Francisco and Ardem Patapoutian of Scripps Research, a biomedical institute in San Diego. Dr Julius did the pioneering work on temperature. He and Dr Patapoutian, acting independently, then advanced this work. After that, Dr Patapoutian moved on to look at mechanical stimulation.

获奖者是加州大学旧金山分校的大卫朱利叶斯和圣地亚哥生物医学研究所斯克里普斯研究所的阿登帕塔普蒂安。Julius 博士在温度方面做了开创性的工作。他和 Patapoutian 博士独立行动，然后推进了这项工作。之后，Patapoutian 博士继续研究机械刺激。

Dr Julius’s chosen tool for his investigation, which he began in the late 1990s, was capsaicin. This is the active ingredient of chilli peppers. By a chemical coincidence (as was then assumed and is now known) capsaicin reacts with, and thus stimulates, one of the body’s heat-receptor proteins. Dr Julius set out to discover what this protein was. To do so he made millions of fragments of genetic material for proteins known to be active in heat-receptor cells. He then introduced these fragments into other cells, to encourage them to manufacture the relevant protein fragments. That done, he tested the modified cells for sensitivity to capsaicin.

朱利叶斯博士在 1990 年代后期开始研究时选择的工具是辣椒素。这是辣椒的活性成分。由于化学上的巧合（正如当时假设的和现在已知的那样），辣椒素与人体的一种热受体蛋白发生反应，从而刺激了它。朱利叶斯博士着手发现这种蛋白质是什么。为此，他为已知在热受体细胞中具有活性的蛋白质制作了数百万个遗传物质片段。然后他将这些片段引入其他细胞，以鼓励它们制造相关的蛋白质片段。完成后，他测试了改良细胞对辣椒素的敏感性。

The fragments which induced capsaicin sensitivity turned out to be parts of a protein now called TRPV1. This belongs to a class of proteins called ion channels, which do many jobs in the body. As predicted, TRPV1 turned out to be heat sensitive. When the temperature rises above 43°C, the channel through it opens, permitting ions of calcium and sodium to pass. That chemical signal stimulates a nerve impulse which tells the brain about the temperature change.

结果证明，诱导辣椒素敏感性的片段是现在称为 TRPV1 的蛋白质的一部分。这属于一类叫做离子通道的蛋白质，它在体内做很多工作。正如预测的那样，TRPV1 对热敏感。当温度升至 43°C 以上时，通过它的通道打开，允许钙和钠离子通过。这种化学信号会刺激神经冲动，告诉大脑温度变化。

TRPV1 turned out to be one of several temperature-sensitive ion channels, some of which register heat, and some cold. It was one of the cold-sensitive varieties, TRPM8, which was discovered simultaneously by Dr Julius and Dr Patapoutian.

结果证明，TRPV1 是几个温度敏感离子通道之一，其中一些记录热，一些记录冷。它是冷敏感品种之一，TRPM8，由 Julius 博士和 Patapoutian 博士同时发现。

Dr Patapoutian then went on to look at the sensation of touch. Molecular biology having advanced in the interim, he was able to work with whole proteins—or, rather, the genes for whole proteins. He identified 72 such proteins expressed in a mechanically sensitive cell line that looked like potential touch-sensitive sensitive ion channels. He tested them one at a time, by silencing the genes that encode them and poking the resulting cells. The first 71 silencings had no effect. But the 72nd proved to be of the protein he was looking for. He called that protein PIEZO1.

Patapoutian 博士然后继续观察触觉。在此期间，分子生物学取得了进展，他能够处理完整蛋白质——或者更确切地说，是完整蛋白质的基因。他鉴定了 72 种在机械敏感细胞系中表达的此类蛋白质，这些细胞系看起来像潜在的触敏离子通道。他通过沉默编码它们的基因并戳戳产生的细胞，一次一个地测试它们。前 71 次沉默没有效果。但事实证明，第 72 个是他正在寻找的蛋白质。他称这种蛋白质为 PIEZO1。

In nature, PIEZO1 is found not in sensory neurons, but rather in organs like the bladder where local sensitivity to pressure is important. But Dr Patapoutian soon discovered a second, similar channel, PIEZO2, which is, indeed, found in nerve endings. It is this that is responsible for touch and proprioception.

在自然界中，PIEZO1 并不存在于感觉神经元中，而是存在于膀胱等器官中，其中对压力的局部敏感性很重要。但是 Patapoutian 博士很快发现了第二个类似的通道 PIEZO2，它确实存在于神经末梢中。正是这一点负责触摸和本体感受。

Fascinating work, then. And important. It is through the senses, and the senses alone, that human beings are able to perceive the world. But to some people the award has come as a surprise. In a year of covid, many had been expecting the honours to go elsewhere—perhaps to the inventors of mRNA-vaccine technology. Like God, however, the various Nobel-prize committees work in mysterious ways their wonders to perform.

那么迷人的工作。而且很重要。正是通过感官，而且仅凭感官，人类才能感知世界。但对一些人来说，这个奖项是出乎意料的。在新冠病毒肆虐的一年中，许多人一直期待荣誉会流向其他地方——也许是 mRNA 疫苗技术的发明者。然而，就像上帝一样，各个诺贝尔奖委员会以神秘的方式运作着他们的奇迹。