美国国家公共电台 NPR Scientists Thread A Nano-Needle To Modify The Genes Of Plants

Scientists Thread A Nano-Needle To Modify The Genes² Of Plants

MICHEL MARTIN, HOST:

Researchers may have cracked a problem that has vexed³ scientists for decades - how to easily modify the genetics of plants. Being able to do that efficiently⁴ would make breeding new varieties of crops faster and easier. NPR's Joe Palca has more.

JOE PALCA, BYLINE⁵: To modify the genetics of plants, you need to get DNA⁶ into plant cells. But it's hard. Researchers at the University of California, Berkeley, have invented a way to do it using something called carbon nanotubes - long, stiff tubes of carbon that are really teeny-tiny. Markita Landry is the scientist who came up with the idea. But the curious thing is she's neither a nanotechnology engineer nor a plant biologist.

MARKITA LANDRY: I'm a physicist⁷. And when I started (laughter) my lab at Berkeley two years ago, my lab was focused exclusively on imaging between cells.

PALCA: Landry was planning to use carbon nanotubes as a kind of external scaffolding around the cells to make it easier to study what was between them. That idea was a total flop⁸.

LANDRY: Because instead of staying outside of the plant cells as we had presumed, these nanotubes were going straight into the cells.

PALCA: So, in the spirit of corporate⁹ management gurus, Landry turned a problem into an opportunity.

LANDRY: We flipped¹⁰ it around and made it a DNA delivery platform instead.

PALCA: Getting DNA into cells would allow scientists to manipulate the way plant cells work. And there are some exotic ways of doing that. But plant cells present a unique challenge.

LANDRY: Plants have not just a cell membrane¹¹ but also a cell wall.

PALCA: A strand¹² of DNA is small enough to slip through the plant cell wall. But it's not rigid¹³ enough.

LANDRY: You can kind of think of it like a floppy¹⁴ string. If you try to push a floppy string through a sponge, it's not really going to work. But if you take a solid needle and try to push it through a sponge, that will work much better.

PALCA: Attaching the DNA to the carbon nanotube gives you that nanoneedle. In addition to DNA, Landry says it's also possible to attach a gene¹ editing tool known as CRISPR. Once inside a cell from, let's say, an apple tree, CRISPR could, for example, inactivate¹⁵ a gene that causes browning in apples.

LANDRY: We would end up with a apple tree whose apples don't go brown when you cut into them.

PALCA: Now, Landry's approach is brand new. Laura Bartley is a plant biologist at the University of Oklahoma in Norman.

LAURA BARTLEY: I think they've got a little ways to go to make it really interesting.

PALCA: She says it's important to show that it works in different varieties of plants. But she's impressed that the new approach appears to be able to get DNA into grass plants like wheat.

BARTLEY: That's the technology that I'm, like, oh, that's pretty cool. If it works the way they think it does, I can imagine a lot of people wanting to use that.

PALCA: In fact, Bartley is thinking about trying the new technique for her work on grass plants.

Joe Palca, NPR News.

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

3 vexed   

adj.争论不休的；（指问题等）棘手的；争论不休的问题；烦恼的v.使烦恼( vex的过去式和过去分词 )；使苦恼；使生气；详细讨论

参考例句：

• The conference spent days discussing the vexed question of border controls. 会议花了几天的时间讨论边境关卡这个难题。
• He was vexed at his failure. 他因失败而懊恼。 来自《现代汉英综合大词典》

4 efficiently   

adv.高效率地，有能力地

参考例句：

• The worker oils the machine to operate it more efficiently.工人给机器上油以使机器运转更有效。
• Local authorities have to learn to allocate resources efficiently.地方政府必须学会有效地分配资源。

5 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

6 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

7 physicist   

n.物理学家，研究物理学的人

参考例句：

• He is a physicist of the first rank.他是一流的物理学家。
• The successful physicist never puts on airs.这位卓有成就的物理学家从不摆架子。

8 flop   

n.失败(者)，扑通一声；vi.笨重地行动，沉重地落下

参考例句：

• The fish gave a flop and landed back in the water.鱼扑通一声又跳回水里。
• The marketing campaign was a flop.The product didn't sell.市场宣传彻底失败，产品卖不出去。

9 corporate   

adj.共同的，全体的；公司的，企业的

参考例句：

• This is our corporate responsibility.这是我们共同的责任。
• His corporate's life will be as short as a rabbit's tail.他的公司的寿命是兔子尾巴长不了。

10 flipped   

轻弹( flip的过去式和过去分词 )； 按（开关）； 快速翻转； 急挥

参考例句：

• The plane flipped and crashed. 飞机猛地翻转，撞毁了。
• The carter flipped at the horse with his whip. 赶大车的人扬鞭朝着马轻轻地抽打。

11 membrane   

n.薄膜，膜皮，羊皮纸

参考例句：

• A vibrating membrane in the ear helps to convey sounds to the brain.耳膜的振动帮助声音传送到大脑。
• A plastic membrane serves as selective diffusion barrier.一层塑料薄膜起着选择性渗透屏障的作用。

12 strand   

vt.使（船）搁浅，使（某人）困于（某地）

参考例句：

• She tucked a loose strand of hair behind her ears.她把一缕散发夹到了耳后。
• The climbers had been stranded by a storm.登山者被暴风雨困住了。

13 rigid   

adj.严格的，死板的；刚硬的，僵硬的

参考例句：

• She became as rigid as adamant.她变得如顽石般的固执。
• The examination was so rigid that nearly all aspirants were ruled out.考试很严，几乎所有的考生都被淘汰了。

14 floppy   

adj.松软的，衰弱的

参考例句：

• She was wearing a big floppy hat.她戴了顶松软的大帽子。
• Can you copy those files onto this floppy disk?你能把那些文件复制到这张软盘上吗？

15 inactivate   

v.使…不活跃

参考例句：

• We put bacteria in an environment at low temperature to inactivate them.我们将细菌置於低温的环境中使之失去活性。
• Food processing destroys some nutrients,but can also inactivate toxins and increase the availability of other nutrients.食物加工破坏一些营养物质，但也可以灭活毒素，并增加其他营养物质的可用性。