Most people try to avoid jellyfish, and their stinging tentacles at all costs. But one lab at Harvard is doing the opposite, they're trying to build jellyfish from scratch. In a paper released on Sunday in Nature Biotechnology, they describe how they successfully reverse engineered a gelatinous jelly in the lab.
Why would someone want to reverse engineer a jellyfish, you might ask. Turns out that nature is way better at building things than we are. By reverse engineering something like a jellyfish, we could improve our own understanding of tissues, and how they work.
So, why jellyfish and not, say, elephants? Or mice? The answer is that way jellies move - using a muscle to pump through the water - is very similar to how the human heart pumps blood. And we would love to be able to build human hearts. Kevin Kit, another author on the study, said the parallel dawned on him several years ago. "I started looking at marine organisms that pump to survive. Then I saw a jellyfish at the New England Aquarium, and I immediately noted both similarities and differences between how the jellyfish pumps and the human heart. The similarities help reveal what you need to do to design a bio-inspired pump."
Fake jellies can also help scientists test drugs, says Kit Parker, the lead researcher on the project. “You’ve got a heart drug?” he asked Nature. “You let me put it on my jellyfish, and I’ll tell you if it can improve the pumping.”
So what does reverse engineering actually entail? Basically, the team wanted to figure out how each component was built, and then how it all fit together. That includes things like how the muscles are arranged, how the body moves, and how the fluid both inside and outside their bodies effects the movements. Then, they build it. This, of course, is not the easy part. In fact, it involves silicone and rat cells.
We found something very interesting right away: the electrical signals that the jellyfish uses to coordinate its pumping are exactly like that of the heart. In the heart, the action potential [electrical signal that travels along nerves – Ed] propagates as a wave through cardiac muscle. That’s how you get this nice, smooth contraction. The activation has to spread like when you drop a pebble in water. The same thing happens in the jellyfish, and I don’t think that’s by accident. My bet is that to get a muscular pump, the electrical activity has got to spread as a wavefront
After we had the map of where every cell was, we took a rat apart and rebuilt it as a jellyfish.
Yep, no big deal, just put the rat back together as a jellyfish. Why not?
The artificial rat turned jelly even swims, when it's subjected to an electric field.