Why love viruses?
Viruses. Frankly, their existence is frustrating. What frustrates me though is not just their efficiency in wreaking havoc in the body, but it’s their simplicity and lack of most things that constitute life – like cellular respiration – and yet they stick around to survive.
Perhaps they were an unavoidable result of evolution, and represent the ‘entities’ that got the best of natural selection (because they don’t need to process any form of energy to operate/eat), or maybe they were an integral part in the evolution of cells and DNA, as 8% of our DNA comes from viral origins.
But we still don’t really know and so our question remains. Viruses are awful, why should we like them?
If you’ve ever had gastro or flu, then you might not even wish such hardship on the antagonist of your worst nightmare.
Lurching out water and bile every few minutes is one thing, but viruses have a lot more to take credit for, from saw throats and nasal congestion to the nasty ones like HIV, Polio and Ebola. These viruses are little more than transcripts or templates for DNA, called RNA wrapped up in a protein coat which is sometimes wrapped in a lipid (unsaturated fat) envelope, yet the damage they can cause to various systems in our bodies is mind numbing.
But after a little research I found that my stigmatisation was perhaps a little out of whack. Various research projects show our history has been intertwined with viruses (forget the ones above) in some interesting ways.
THE FRONT LINE (OUR MECENARY ARMY)
The gut is a hellish battlefield. The dangerous no man’s land where food is processed to move onto the next zone/stage of digestion. The flood of gastric juices with a 1.5 pH acidity, ionises and destroys harmful bacteria and viruses. Enzymes are spitting out molecules at blinding speeds. Stomach wall muscles contract, mixing and churning the melting soup of nutrition. But some persistent bacteria do survive and pose a threat to our well being.
Mucus is a wonderful thing; like the fort wall or barrier protecting the healthy cells of the stomach and lungs from acid and most of dangers that the outside world hands to us on a silver platter. It makes a theatrical appearance when you have the flu, and is great for trapping things in your nostrils. It also houses viruses (phages), but these ones have agreed to help.
Like a strange symbiosis of mutual caring. The viruses destroy the persistent bacteria and protect us from infection, and they benefit from the steady stream of the microbes drifting by, which they can hijack to reproduce and survive.
Yes! DESTROY it my little peasan… oh me? No its nothing just keep on with the good job… Photo credit: Dr Graham Beards at Wikimedia Commons.
THEY SUPPORT A MOTHER’S LOVE.
If it wasn’t for the viruses that infected your ancestors egg and sperm hundreds of millions of years ago, you wouldn’t have been born. It turns out that the protein called Syncytin is required for the formation of Syncytiotrophoblast, a single cellular layer or ‘thin sheet’ on the placenta. This layer is needed for the exchange of nutrients between the foetus and the mother. Yet this syncytin’s resourcefulness doesn’t stop there. Through a ‘cunning viral trick’ this protein tones down the mother’s immune activity to protect the baby from being targeted as a foreign invader.
Syncytin is also found in gorillias and chimpanzees, meaning the virus infected a common ancestor of ours (a long long time ago) Photo credit: BanyanTree on Wikimedia Commons.
A protein made by retroviruses – which elbowed its way into our genome (taking permanent residence in our DNA) – helped humans evolve the placenta. It has also been known for many years that viral ‘colonies’ ‘live’ in our skin, blood, and various organs of our body. Many mysteries are yet to be solved on how these viruses interact with us, and our long incredible history with these strange DNA engineers.
These viruses have been invested in human affairs long before we studied them and waged war against their kin. Long before we even questioned why people got runny noses. It goes to show just how deep our relations with these seemingly foreign invaders really are.
Now it’s time to rethink how we see viruses as a whole, with the good and the bad, because we definitely don’t want to make enemies with the good ones.