“Weed Eater” Protein May Destroy Viruses Without Damaging Cells
I still remember the first time I used a weed eater as a kid mowing the lawn. It was an amazing experience of power over weeds and, frankly, anything else that got in its way. Now scientists have discovered a weed eater protein that can shred viruses the same way that a weed eater shreds those lawn weeds.
We’re Under Constant Viral Invasion
Viruses invade our bodies every second of the day. We are constantly breathing them in or ingesting them. Bug bites and intimate contact with another person transmits them. We can’t escape them, but as often as we take them in, they rarely lead to an infection. Our immune system does a pretty good job, most of the time, of getting rid of them before they can do much damage.
However, when the virus is particularly aggressive or encounters a sluggish cell or weakened immune system, we may be unable to evade its attack. The list of viral infections is lengthy, but it includes the common cold, chickenpox, influenza, HIV, and even some long-since eradicated viruses (in the U.S.), such as yellow fever and polio.
The problem with a virus is that once it does cause an infection, there’s no good and fast way to knock it out. For a cold, you might be able pop a lozenge to temporarily relieve a sore throat, or with chickenpox, you might be able to douse the blisters in anti-itch cream, but for the most part, the virus simply has to run its course. In addition, many viruses can be quite debilitating and even deadly. So it’s no surprise that science is constantly studying viruses in the hopes for better treatment solutions.
Today’s feature study may put science a step closer, but first let’s look at what happens when a virus successfully attacks.
What Is a Virus, and How Does It Attack?
While a virus does contain genetic material, it contains no cells and is not technically living. It is essentially just a protein shell (called a capsid) that contains either RNA or DNA. Therefore, it needs a host, or a susceptible living cell, in which to do its dirty work. Once inside a cell, the virus releases its genetic code (RNA or DNA), which integrates itself into the host cell’s own DNA and protein-manufacturing process. The cell then replicates the invading virus and makes copy after copy of the virus. The process quickly intensifies, and when the cell has produced more copies of the virus than it can hold or when the virus has depleted the energy of the cell, the copies escape from the cell, usually killing the cell, and seek new host cells to infect.
Unlike bacteria, which are living cells that infect us by invading our bodies, feeding off the environment, and then growing and dividing on their own, viruses must have a living host cell in order to survive and replicate. And they aren’t picky. Human cells aren’t their only target; viruses will attack pretty much anything with a cell: animals, plants, even bacteria. While antibiotics are a common way to eradicate a bacterial infection, they are useless against a virus that has invaded a host cell. So the challenge with a viral infection is in how to destroy the virus without damaging the host cell it has invaded.
Researchers believe they may be getting closer to a solution.
Dicer Protein Weed-Eats Virus, Leaves Cell Intact
Findings from a new study suggest there may be a way to destroy viruses without damaging the host cells they invade. Researchers believe they have found the answer in, of all things, the tiny fruit fly and a protein it naturally produces. Named the Dicer, the protein functions like a virus weed eater, first identifying a virus that’s close by and then grabbing its RNA strand with a death grip and pulling it in while shredding the genetic material into pieces.
How does the Dicer protein tell the difference between the virus’s RNA and the host cell’s RNA? The researchers believe the protein is drawn to a very minute detail in the double-stranded RNA. In the host cell’s RNA, the end of one strand is slightly shorter than the other, while in the virus’s RNA, both strands are equal. So it seems that those equal RNA strands are all it takes to send Dicer into a virus-slashing rage.
Researchers hope the finding in fruit flies will parallel in some way to the functionality of the Dicer protein (being able to distinguish and destroy viruses without damaging the cell) in humans and help them discover new ways to fight viral infections.
The upshot? Maybe our newest anti-viral drug will have more in common with a weed eater? More research will be needed to ensure this approach to killing viruses is safe in humans, but what’s not to like about shredding viruses?