Get a spine!

This may not be news to the rest of the world…but it’s news to me and might be news to you.

I learned this morning from Pro­fessor Gün­ther Zupanc that a teleost fish can grow a new back­bone if you cut it in half. I used to do this to earth worms in my sandbox as a child (does that make me a can­di­date for the cer­ti­fi­able cat­e­gory?), and marvel at the fact that it didn’t kill them. But earth­worms don’t have backbones…or any bones for that matter. It’s not a real bio­log­ical feat to grow new skin cells –  we do it all the time.

No, this spe­cial skill of the teleost fish is a tes­ta­ment to its evo­lu­tionary savvy. Fish in gen­eral can regen­erate neu­rons very well, said Zupanc. But this species is par­tic­u­larly good at it because of an ancient preda­tory rela­tion­ship, which Zupanc explained to me:

It’s very inter­esting from a bio­log­ical point of view. They live in South America and these crea­tures, unfor­tu­nately, they have preda­tors that spe­cialize on eating their tails and in the tail is part of the spinal cord. So basi­cally they lose part of the spinal cord all the time and in order to sur­vive they have to be able to regen­erate. So they regrow their spinal cord and these other beasts — they eat part of the spinal cord all the time.

Mam­mals have a much harder time growing new neu­rons in gen­eral, and growing new neu­rons in the spinal cord is espe­cially dif­fi­cult. If humans were able to regen­erate spinal cord cells like teleost fish, it would mean healing from a broken neck in about eight weeks. Zupanc’s mis­sion is to better under­stand neu­ronal sys­tems that are good at gen­er­ating new cells in order to under­stand those that are not so good at it — like ours.

Here’s a video Zupanc’s lab put together to illus­trate the regrowth process. For more info, visit his web­site here.