Those of you who have taken a biology course are probably familiar with the immune system. Antibodies and white blood cells seek out and destroy pathogens that invade our bodies.
But you might not know that plants protect themselves from disease very differently than we do.
The public should know how IU researchers use this knowledge to fight disease.
While the animal immune system can be likened to a game of cops and robbers, wherein the white bloods cells act like cops looking for the criminal pathogens, the plant immune system is similar to a home security system.
Rather than detecting a burglar directly, a plant’s immune system sounds an alarm when it detects the broken door or window that pathogens used to enter.
A team at IU led by Roger Innes, a professor of biology at IU, has spent years trying to genetically modify plants to be resistant to diseases that don’t trigger the plant’s alarm system.
The team members recently achieved a huge success and published their results in the journal Science.
The team’s research fills a gap in the understanding of the plant immune system and how it can be manipulated to benefit mankind.
When a plant becomes infected with disease, the immune response is not triggered by the pathogen directly, but by the damage the pathogen causes.
Most plant diseases cause damage using proteases, or enzymes that chop up the proteins plant cells need.
In order to detect damage, the plants deploy a decoy — a protein designed by the plant to be chopped up by the pathogen’s proteases. These decoy proteins are highly specific and, in the case of the lab rat of the plant science world Arabidopsis thaliana, they detect only damage by a specific species of pathogenic bacteria.
Innes’ team found they could modify just seven amino acids, the building blocks of proteins, in the plant’s natural alarm system to make the plant resistant to pathogens to which it was previously vulnerable.
The results have huge implications for agriculture.
We can protect crops from disease not only without chemical pesticides — to which pathogens develop resistance — but without foreign genes which produce pathogen-resistant plants.
Since the technique modifies genes already present in the plant rather than adding new ones, it’s different from current regulations surrounding GMO crops. By avoiding the regulatory system surrounding GMOs, Innes hopes this technology can become cheap and more widely available.
These regulations require extensive field and animal testing, which places huge financial demands on companies looking to develop the technology.
It means a few big firms control GMO technology.
If more smaller companies developed resistant crops using Innes’ breakthrough, the resistant crops could be available to developing regions that can’t afford expensive GMOs or chemical pesticides.
This worked in Arabidopsis thaliana, a plant with no agricultural relevance, but the lab is working on applying it to soybean and barley.
Innes devoted his life to science so he could reduce agriculture’s dependence on dangerous chemicals, and now he is one massive step closer to achieving this goal.
jaykgold@indiana.edu
@JayKeche
