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Paralyzing Worms With Light

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Paralyzing Worms With Light

Paralyzing Worms With Light

Paralyzing Worms With Light

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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Feed nematode worms a particular light-sensitive chemical and after the meal, the worms become paralyzed when exposed to UV light. Remarkably, the effects can be reversed under visible light, Neil Branda and colleagues report in the Journal of the American Chemical Society.

JOE PALCA, host:

And that flute music can only mean one thing. It means we've reached that hour, that moment in the hour when we talk to the fabulous Flora Lichtman about the video pick of the week. Flora, what's up?


PALCA: Hi, Flora. What's up?


PALCA: Thank you very much. It's a delight to be here and thank you so much for having me. OK.

LICHTMAN: OK. Down to business.

PALCA: Down to business.

LICHTMAN: This week, we have a story about scientists who have basically made a stun gun for worms.

PALCA: A stun gun for worms. What does that mean?

LICHTMAN: Very important research.

PALCA: Yeah, right. Because a lot of worms. You know, worm attacks are being rampant all over the place.

LICHTMAN: All right.

PALCA: No, it's more important than that.

LICHTMAN: All right, so here's the story. Neil Branda - who's a chemist at Simon Fraser University in Canada - and his colleagues took a nematode worm, also known as C. elegans, this experimental model organism, they fed it a light-sensitive chemical. So that's a chemical that changes when you expose it to different types of light.

PALCA: Mm-hmm.

LICHTMAN: And then they shined the worm with UV light.

PALCA: Ultraviolet light, OK.

LICHTMAN: Ultraviolet light. And something kind of remarkable happened. First, the worm turned blue�

PALCA: Mm-hmm.

LICHTMAN: �which is kind of a side point, and then it became paralyzed.

PALCA: Paralyzed?

LICTHMAN: So here's where the stun comes in.

PALCA: You don't think it's just resting?

(Soundbite of laughter)

LICHTMAN: Apparently, enough worms started resting after the UV light had been�

PALCA: Right. OK. So they decided it was paralyzed. OK.

LICHTMAN: And then the next part - and here's where it's new - when they shined the worms back with visible light�

PALCA: Mm-hmm.

LICTHMAN: �they started moving again.

PALCA: So this was a reversible�

LICHTMAN: Reversible�

PALCA: �stun�

LICHTMAN: �mechanism.

PALCA: �mechanism that's switched on and off by light.



LICHTMAN: And you can see it on our Web site, at

PALCA: I knew that was coming. No, I actually, I have to confess. I took a peek out of it. It's pretty remarkable. You should go have a look. Flora, thank you very much.

LICHTMAN: Joe, thank you.

PALCA: OK. And that's it for today's hour. Flora Lichtman is the digital media producer for SCIENCE FRIDAY, and that was her you were just hearing.

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