2012年诺贝尔化学奖Robert J. Lefkowitz和Brian K. Kobilka
Robert J. Lefkowitz来自杜克大学，Brian K. Kobilka来自斯坦福大学。因发现G蛋白欧联受体研究而获奖。

你的身体是一个精妙调和的系统，几十亿细胞之间相互作用。每一个细胞都具有微小的受体，使其可以感知周围环境，以适应新情况。罗伯特·莱夫科维茨和布莱恩·克比尔卡被授予2012年诺贝尔化学奖，因为他们的突破性发现揭示了这种受体的一个重要家族：G蛋白偶联受体的内部工作机理。

长期以来，人们并不清楚细胞如何感知周围环境。科学家知道肾上腺素等激素可以发挥强大的作用：提高血压，加快心跳。他们怀疑细胞表面存在某种激素的接收器。但是这些接收器究竟由什么组成、如何工作，在20世纪大部分时间里仍然是一个未解之谜。

Lefkowitz在1968年开始利用放射性方法追踪细胞受体。他将同位素碘连接在多种激素分子上，在辐射的作用下，他得以发现若干种受体，其中包括一种肾上腺素受体：β肾上腺素受体。他的团队从细胞膜中分离出了隐藏其中的受体，并初步得出了它们的工作机制。

团队在1980年代取得了进一步的突破。后来招进的Kobilka接受了从庞大的人类基因组中分离编码β肾上腺素受体基因的挑战。他具有创造性的方法使他达成了目标。当研究者们分析这一基因是，他们发现这一受体与眼中的一个感光受体相似。他们意识到存在一个受体家族，它们彼此结构类似，而且以相同的方式产生功能。

今天这个蛋白家族被称为G蛋白偶联受体，大约1000个基因为这些受体编码；这些受体涵盖了光线、嗅觉、味觉、肾上腺素、组胺、多巴胺还有五羟色胺等多个领域。所有药物里大约一半是通过G蛋白偶联受体发挥作用的。

团队在1980年代取得了进一步的突破。后来招进的Kobilka接受了从庞大的人类基因组中分离编码β肾上腺素受体基因的挑战。他具有创造性的方法使他达成了目标。当研究者们分析这一基因是，他们发现这一受体与眼中的一个感光受体相似。他们意识到存在一个受体家族，它们彼此结构类似，而且以相同的方式产生功能。

Lefkowitz and Kobilka 的研究对于理解G蛋白偶联受体发挥作用的方式至关重要。特别是2011年，Kobilka
又取得了另一项重大突破：他和他的研究组捕捉到了β-肾上腺素受体被激素激活、向细胞发送信号的那一瞬间的景象。这幅图片本身就是分子尺度的大师之作——是数十年研究的结晶。
 

10 October 2012

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2012 to

Robert J. Lefkowitz
Howard Hughes Medical Institute and Duke University Medical Center, Durham, NC, USA

and

Brian K. Kobilka
Stanford University School of Medicine, Stanford, CA, USA

"for studies of G-protein–coupled receptors"

Smart receptors on cell surfaces

Your body is a fine-tuned system of interactions between billions of cells. Each cell has tiny receptors that enable it to sense its environment, so it can adapt to new situtations. Robert Lefkowitz and Brian Kobilka are awarded the 2012 Nobel Prize in Chemistry for groundbreaking discoveries that reveal the inner workings of an important family of such receptors: G-protein–coupled receptors.

For a long time, it remained a mystery how cells could sense their environment. Scientists knew that hormones such as adrenalin had powerful effects: increasing blood pressure and making the heart beat faster. They suspected that cell surfaces contained some kind of recipient for hormones. But what these receptors actually consisted of and how they worked remained obscured for most of the 20th Century.

Lefkowitz started to use radioactivity in 1968 in order to trace cells' receptors. He attached an iodine isotope to various hormones, and thanks to the radiation, he managed to unveil several receptors, among those a receptor for adrenalin: β-adrenergic receptor. His team of researchers extracted the receptor from its hiding place in the cell wall and gained an initial understanding of how it works.

The team achieved its next big step during the 1980s. The newly recruited Kobilka accepted the challenge to isolate the gene that codes for the β-adrenergic receptor from the gigantic human genome. His creative approach allowed him to attain his goal. When the researchers analyzed the gene, they discovered that the receptor was similar to one in the eye that captures light. They realized that there is a whole family of receptors that look alike and function in the same manner.

Today this family is referred to as G-protein–coupled receptors. About a thousand genes code for such receptors, for example, for light, flavour, odour, adrenalin, histamine, dopamine and serotonin. About half of all medications achieve their effect through G-protein–coupled receptors.

The studies by Lefkowitz and Kobilka are crucial for understanding how G-protein–coupled receptors function. Furthermore, in 2011, Kobilka achieved another break-through; he and his research team captured an image of the β-adrenergic receptor at the exact moment that it is activated by a hormone and sends a signal into the cell. This image is a molecular masterpiece – the result of decades of research.