纪录片《长生不老》 08长寿基因（在线收听）

For scientists like David,

对像大卫这样的科学家

yeast is the perfect research specimen.

以酵母为研究对象再适合不过了

It's a simple organism with only

它是只有6000个基因的简单组织

6,000 genes, a tenth the amount we have,

是我们拥有的十分之一

so it makes much easier to hunt for particular genes.

所以找特殊基因会更简单

And surprisingly almost all the genes in yeast exist in humans.

惊讶的是人体内几乎有酵母所有的基因

After seven years, he was able to identify a gene for longevity.

7年后 他找到了长寿基因

The yeast cells are microscopic

酵母细胞极小

so we look at them under the microscope

所以我们要在显微镜下看

count how many times they divide,

数数它们分裂几次

and what we're looking for were genes that if you delete them,

我们要确定去掉其中的哪个

or you add an extra copy of them, that they live longer,

或加入哪个复制体 它们会活得更久

and we found a set of genes that do that.

我们找到了这样的一组基因

They're called the sirtuin genes and really what was

它们叫做沉默调节蛋白基因

very exciting was that just adding one extra copy of a gene

让人激动的是仅需加入一个该复制体

called sirtuin could greatly

就能大大延寿

extend the lifespan of those yeast, about 30%.

延长大约30%的寿命

David had a hunch that this longevity

大卫预感这个长寿基因

gene was key to how calorie restriction worked.

是控制卡路里摄入的关键

What he needed to do was to prove the link.

他需要做的是证明这其中的联系