Goshen News, Goshen, IN

Community News Network

March 4, 2013

Can eyes see outside of the head?

PITTSBURGH — Recently, we have witnessed remarkable, fictional-sounding advancements in science and medicine. There's a guy who can hear color, another with a bionic eye attached to his brain, and a woman fighting back against the debilitating symptoms of multiple sclerosis by placing electrodes on her tongue. But for our next trick, we're going to need a bucket of tadpoles with eyes on their butts and some good old-fashioned alternating current. In other words, things are about to get all kinds of weird.

There's a great deal of wow to unpack here, so let's take it piece by piece. Using embryos from the African clawed frog (Xenopus), scientists at Tufts' Center for Regenerative and Developmental Biology were able to transplant eye primordia — basically, the little nubs of flesh that will eventually grow into an eye — from one tadpole's head to another's posterior, flank or tail. They don't play around with nerve endings or "wiring" or anything like that. They just cut out the cells from the head, slice open a bit of the tail, and jam them in.

As the eyes grow, they send out snaking tendrils of nerve fiber, or axons. We know this because the "tissue donor" tadpoles — a term that makes it sound like they had a choice — were injected with tdTomato, a fluorescent red protein. This allowed the researchers to watch innervation, or nerve growth, as it happened. Of those eye primordia that sent out feelers, nearly half hardwired directly into the spine, while the other half built connections to the nearby stomach. None of the tadpoles grew tdTomato-marked pathways to the brain.

Before they could test the ectopic eyes however, the native ones had to be severed and removed. Otherwise, how would the scientists know which of the tadpole's three eyes was truly seeing? (Note: Severing optical nerves sounds like nasty business, but even these partially-developed tadpoles received anesthesia via fish sedative. Wounds healed completely within 24 hours.)

Text Only
Community News Network
Parade
Magazine

Click HERE to read all your Parade favorites including Hollywood Wire, Celebrity interviews and photo galleries, Food recipes and cooking tips, Games and lots more.
AP Video
Raw: Gunmen Attack Iraqi Prison Convoy Plane Leaves Ukraine With More Crash Victims The Rock Brings Star Power to Premiere Raw: Families Travel to Taiwan Plane Crash Site Arizona Execution Takes Almost Two Hours Gen. Odierno Discusses Ukraine, NATO at Forum Gaza Fighting Rages Amid Cease-Fire Efforts Mint Gives JFK Coin a Face-lift Creative Makeovers for Ugly Cellphone Towers Ariz. Inmate Dies 2 Hours After Execution Began Crash Kills Teen Pilot Seeking World Record LeBron James Sends Apology Treat to Neighbors Raw: Funeral for Man Who Died in NYPD Custody Migrants Back in Honduras After US Deports Israeli American Reservist Torn Over Return
Poll

Last weekend (July 12) the Goshen Parks Department held its Kid’s Try-athlon to promote childhood fitness and this week (July 18) the new bicycle trail is open to the fairgrounds in Goshen, offering residents a healthy way to get to the annual agriculture exposition. Have you joined the local fitness movement?

Yes, I work at eating healthy and exercising
No, I am happy with my fitness level
Changing my diet and exercise frequency is a work in progress
     View Results