Scientists believe this work could guide corn research for “the next decade.”
Plant stem cells are vital to the world’s food supply, animal feed, and fuel production. They form the foundation for how plants grow, yet much about these building blocks remains unknown. Past studies have struggled to identify many of the genes that control how stem cells function.
Researchers at Cold Spring Harbor Laboratory (CSHL) have now mapped two known stem cell regulators across thousands of maize and Arabidopsis thaliana shoot cells. They also discovered new stem cell regulators in both species and connected some to size variations in maize. The method they used to recover rare stem cells could work across the plant kingdom.
“Ideally, we would like to know how to make a stem cell,” CSHL professor David Jackson said in a recent news release. “It would enable us to regenerate plants better. It would allow us to understand plant diversity. One thing people are very excited about is breeding new crops that are more resilient or more productive. We don’t yet have a full list of regulators—the genes we need to do that.”
Jackson and his colleagues began with two well-known stem cell regulators, CLAVATA3 and WUSCHEL. Xiaosa Xu, a former postdoc in Jackson’s lab, dissected a small piece of maize and Arabidopsis shoots containing stem cells. The team used a microfluidics machine to separate each cell, convert its RNA into DNA, and label it with a tag showing which cell it came from.
This process, called single-cell RNA sequencing, shows how genes are expressed in thousands of cells at once.
“The great thing is that you have this atlas of gene expression,” Jackson said. “When we publish that, the whole community can use it. Other people interested in maize or Arabidopsis stem cells don’t have to repeat the experiment. They will be able to use our data.”
Using single-cell RNA sequencing, the team recovered about 5,000 CLAVATA3 and 1,000 WUSCHEL-expressing cells. They identified hundreds of genes that were expressed in both maize and Arabidopsis stem cells, suggesting these genes may be evolutionarily important across plant species. They also linked certain stem cell regulators to productivity in maize — connections that could someday help breeders select specific strains for food, animal feed, or fuel production.
“It’s foundational knowledge that could guide research for the next decade,” Jackson said. “It can be used not only by developmental biologists, but physiologists, who think about how corn ears grow and how to improve productivity, and then breeders.”