Genetics, Plant Biology
University of California, Davis
Dr. Dubcovsky is a Howard Hughes Medical Institute–Gordon and Betty Moore Foundation investigator. He is also a distinguished professor of plant sciences at the University of California, Davis.
Development of Genomic Tools to Dissect Regulatory Gene Networks in Wheat
Studying wheat at the micro level has enabled Jorge Dubcovsky to have a macro level impact on the world's food supply. By identifying and then reinserting a gene that the plant lost over centuries of cultivation, he boosted the grain's protein, zinc, and iron content to make it more nutritious. Following those successes in the laboratory, he has helped distribute the improved seeds to countries around the world.
Dubcovsky grew up in Argentina in the 1960s and '70s, and the era had a lasting impact on him. "I came into science with the ideals from the '70s, with strong social consciousness and the will to do something useful," he says. "I'm concerned about poverty—I saw it many, many times in my country, and it bugs me not to do anything for that." He found a way to make a difference through wheat genetics. "Twenty percent of what every person around the world eats, every day, is wheat. Anything you do that would make that crop better has a huge impact," he says.
He didn't start out studying genetics. Thirty years ago, Dubcovsky was making a difference in another realm, teaching middle school math and science classes and taking university-level science classes so he could better understand his subjects. During those classes, he fell in love with research, so after earning an undergraduate degree he decided to pursue a Ph.D. in the genetics and evolution of Patagonian grasses. "Those grasses live in pretty hostile environments, with cold, strong winds blowing all the time," he says. "I was looking at the plants in their real environment, looking at their evolution and how they've changed. That's an important perspective when you go into breeding and you're trying to improve plants' abilities to survive."
After completing his doctoral research at the University of Buenos Aires, Dubcovsky discovered the power of emerging technologies in molecular biology and took a fellowship at the University of California at Davis. "For the first time, with these new molecular markers, we were able to answer questions in a way that just wasn't possible before. We were able to generate the first molecular genetics maps in wheat."
In 1994, he returned to Argentina; after two years of working as a scientist there, Dubcovsky went back to Davis to direct the wheat-breeding program, where he remains today. His understanding of how grasses adapt and evolve in their native environments, combined with his decades of research in chromosomal inheritance and molecular biology, have allowed him to make significant contributions to the field of wheat genetics.
Dubcovsky has forged new territory in wheat genetics—mapping, isolating, and cloning developmental genes from the plant's huge, unsequenced genome. His discovery of how to boost protein content in cultivated wheat was just the beginning of an in-depth, molecular investigation into the plant's aging process: His group discovered that the gene they reinserted, GPC-B1, is effective because it allows wheat grass to move nitrogen faster and more efficiently from leaf to grain, allowing additional nutrients to be ferried into the seed before the plant dies.
Dubcovsky's lab is investigating critical stages of the wheat plant's developmental cycle, cloning genes involved in flowering initiation, spike development, and senescence. The more researchers understand about how genes modify these processes, the better equipped they are to breed varieties that are matched to the climate—flowering and maturing earlier or later—and even to produce more grains per stalk. He's cloned the main three wheat "vernalization" genes that are vital to the timing of flowering and is now working on others that can increase yield (the number of grains per stalk) and pathogen resistance. Wheat breeders can use this information to engineer precisely the flowering time of their varieties and make them better adapted for particular climates—a growing necessity for farmers confronted with a warming planet. "The impact of our lab has been on cloning genes that were agronomically important: The applied genes for flowering, protein content, disease resistance, and the translation of all those things into real, concrete varieties that people can eat," he says.
Dubcovsky's genetic work has already forged a path through previously unnavigable terrain, and he continues to push forward in multiple areas of wheat genetics. But he anxiously awaits the day when the wheat genome is fully sequenced, a difficult task in a plant with multiple copies of immense chromosomes. "I think it's immoral that we are sequencing hundreds of genomes from the model species but we don't have a sequence for wheat," Dubcovsky says. Every cloning project he has completed involves two to three years of work to construct a physical map of the target region—a length of time that could easily be quartered, he says, if he had a full genome to work from. Until then, he will keep pushing hard to translate his lab research into edible results.