You Call It Corn Stem Cells, We Call It An A-Maize-Ing Hope to Feed the World

figure_6A

David Jackson and his team at Cold Spring Harbor Laboratory identify a unique genetic pathway that regulated stem cell growth. Certain mutations in the pathway lead to increased plant yields (two plants on the right). Image: Cold Spring Harbor Laboratory

Here at the Stem Cellar, we’re laser-beam focused on the exciting progress being made to bring stem cell-based treatments to patients with unmet medical needs. But what good will those life-saving treatments be if the patients end up starving from hunger? It’s a serious question to ask considering the world’s diminishing farmlands and yet another record-breaking month for global warming in the books.

Based on a study published yesterday by Cold Spring Harbor Laboratory researchers, our friend the stem cell emerges again as a source of hope. Reporting in Nature Genetics, the team uncovered an important genetic switch in the stem cells of corn that when manipulated can lead to a 50% increase in the size of the corn.

Plants have stem cells too
Plants do indeed have stem cells that reside in an area called the meristem and function similarly to their animal counterparts. The root apical meristem is responsible for providing cells for root growth while the shoot apical meristem gives rise to plant organs like leaves and flowers. Previous research had shown that a signal system within the meristem communicates whether or not to turn on stem cell growth. The current study identified protein signals involved in a similar regulatory circuit but with an intriguing difference which David Jackson, the lead author on the study, explained in a Cold Spring Harbor video (see below):

“In this new study we found that actually the leaves, the developing leaves, send a signal back to the stem cells to control their growth which is really a new finding.”

FCP-1/FEA3: A Leaf to Stem Cell Braking System
The proteins involved in this signal include a receptor protein on the stem cells called FEA3 and a protein from the leaves called FCP-1. When it travels from the leaves to the stem cells, FCP-1 binds to FEA3 causing an inhibition of stem cell growth. So you’d think that disrupting this pathway would release the “brake” on stem cell growth and lead to tractor-sized corn. But when the team tested that idea by growing plants with a fea3 mutation, the resulting crop was short and stubby. The explanation is that too many stem cells is not a good thing and the available water, sunlight, and soil is not enough to support increased growth.

Easing off the brakes is better for crop yields
So as a result of uncontrolled stem cell growth, the corn becomes deformed and leads to a poorer yield. But next, the team analyzed plants with weaker versions, or alleles, of the fea3 mutations. Basically, these mutations still lead to a release of the “brake” on stem cell growth but not as quite as much as the initial fea3 mutation. Under this genetic scenario, the plants grew extra rows of kernels with up to 50% increase in yield.

Because the FCP-1/FEA3 pathway is found throughout the plant kingdom, this result has the tantalizing potential to help increase yields of all sorts of food crops.  As Jackson mentions in an interview with Gizmodo, this future will depend on these laboratory experiments working in a real world setting:

“If the yield increases we have seen in our lab strains hold out when used in agricultural maize strains this would lead to a significant boost in yields, potentially improving agricultural sustainability by requiring less land be devoted to agriculture. The same approaches could also benefit farmers in developing countries growing a wide range of crops.”

Certainly this future crop would be considered a genetically modified organism (GMO) which may concern some. But just today the National Academies of Sciences, Engineering, and Medicine posted evidence on their website that points to GMO foods as being safe and good for the environment.

Leave a comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.