Current Research and Cells
Every year around the world, billions of dollars' worth of crops are damaged by tiny little roundworms called nematodes.12 Remember when SpongeBob lost his pineapple home to nematodes? Because the impact of nematodes is so large, governments, universities, and agricultural businesses spend millions of dollars every year trying to understand two things:
- How nematodes harm plants
- How to prevent them from doing so in the future
One of the most interesting things biologists have learned in the course of this research is that many nematodes are capable of hijacking plant cells.13
The process of plant cell hijacking goes something like this:
- A nematode crawling through the soil will encounter a plant root cell. Nematodes are tiny, to be sure.
- Using a special oral spear called a stylet, the nematode will inject a series of enzymes directly into the plant cell cytoplasm.
Here is an example:
These enzymes eventually make their way to the nucleus and reprogram some of the plant cell’s DNA. This is not just a random re-programming, mind you. The hijacking enzymes basically cause the plant cell to start making nutrients for the nematode, instead of for the plant. They also cause the plant cell to grow very large and convince neighboring cells to do the same. Oh noes!
Before long, a huge mass of giant plant cells, called a syncytium, is formed that can feed many, many nematodes for days. Research has shown that nematode hijacking enzymes can cause complex changes in which plant genes are turned on and off.14 For instance, recent studies have shown that nematode enzymes can turn on plant genes that make proteins to break down cell walls.15 This cell wall degradation allows for syncytia to form and for nematode infection to proceed more quickly. This is bad, bad, bad for the plant.
While a few nematodes might not do any noticeable damage to a plant, if too many syncytia are formed, plant growth can suffer dramatically. It’s the accumulated effect of trillions of nematodes hijacking trillions of plant cells that causes such incredible crop loss worldwide—and it all happens at the cellular level!