Otherways- Fiction Fanatics

When I was in Biology class umptamillion years ago, we had to define life. To be perfectly honest, I thought it was the stupidest assignment I’d ever been given. Life is obvious, right? A bison is alive, a stone isn’t, and generally we know at first glance whether a thing is alive or not. Defining life turned out to be a bit trickier, and the more we learn, the harder it seems to get.

Living things grow, they replicate, and they take in nourishment. Those are the simplest factors defining life. Obviously this fits the bison, and not so much on our example stone. It is possible, of course, to smash the rock and generate a lot of tiny rocks, but no matter how well you feed them, they will never grow to become larger rocks. According to that old class, single celled organisms were the simplest form of life, and viruses were still being debated. Now we naturally accept that a virus, which is essentially DNA in a protein case, is in fact a living organism, and we aren’t quite sure what to do with prions.

Whether you think so or not, you’ve heard of prions. They’re the jerks responsible for Mad Cow disease, among other things.

Prions first came to light in the study of a disease in New Guinea called Kuru by the locals. The name translates roughly into “trembling in fear”, and was first observed in the ‘50’s by trained medical staff. It’s a neurological disease, where victims gradually lose control over their motor functions, eventually being unable to even swallow, and inevitably die. Though we didn’t realize it then, this is caused by prions in the brain tissue.

To me, prion sounded like a chemical name, not a creature, and strangely that wasn’t far from the case. They are complex proteins with the (we think) unique capability of reproducing themselves. Not all prions are disease causing, as they have two forms. In proper scientific form they’ve given the two forms unpronounceable gibberish names : PrP-sen is the benign form, and PrP- res is the complete jerk.

Dr. Stanley Prusiner coined the name prion in his research into these debilitating diseases. It is short for PROteinaceous INfectious organism. He also demonstrated that the stuff was infectious to humans, and won the Nobel prize in Medecine in 1997. Meanwhile cows in Britain were starting to show signs of Mad Cow disease, another “spongiform” disease like Kuru. They’re called spongiform diseases because of the holes that infected creatures have in their brain tissue. More than 155 people would eventually die in England from ingesting meat tainted with these “new” disease causing organisms.

Kuru, Mad Cow Disease, Chronic Wasting Disease in deer and Elk, and Creutzfeldt-Jakobs disease in humans are all caused by prions. So we have spent a good deal of time and money trying to figure out how to fight or prevent the problems they cause, but we’ve run into a bit of a snag. You see, most of what we fight is alive, and all we have to do is figure out what kills it. Prions, although they do behave rather like living organisms, aren’t, at least not exactly. Which means killing them isn’t easy. They’ve tried radiation, boiling, acid, standard hospital sterilization techniques, and had no success. Even the brains that have been sitting on a shelf somewhere for decades preserved in formaldehyde were still capable of engendering the disease in new subjects.

Life isn’t as simple as I once thought it was. Prions may well be a window into what the very first life on earth was like, self-replicating protein strands. The fact that they now seem to “live” to eat our brains is a bit creepy, but still fascinating.

Cheers,

Michelle