Professor and Director
Plant Molecular and Cellular Biology
Howard Hughes Medical Institute Investigator
Howard H. and Maryam R. Newman Chair in Plant Biology
Plant science is needed more today than ever before to help meet the demands of a rapidly growing human population and the disruptions of climate change. The global population recently topped 7 billion and is expected to reach 12 billion by the end of the century. More people means greater demand for food, feed, fiber and fuel, placing tremendous strains on ecosystems around the world. This growing demand, combined with extreme drought and temperature fluctuations, has resulted in widespread environmental damage, economic hardship and malnutrition. It is estimated that one in seven people currently do not have enough to eat, and complications from malnutrition are the greatest killer of children under five.
Joanne Chory has spent more than 25 years using Arabidopsis thaliana, a small flowering mustard plant, as a model for plant growth. She has pioneered the use of molecular genetics to study how plants respond to their environment and has made major discoveries surrounding how plants sense light and make growth hormones. The basis of Chory’s approach involves mutating Arabidopsis genes and then observing the effects on a plant—does it grow faster or taller? Does it stop sending new shoots out in the direction of the sun? Does it need less water? In this way, her team has been able to describe the function of multiple pathways that control plant growth.
Chory and her team run a vertically integrated program, using genetics, genomics, cell biology, x-ray crystallography, biochemistry and ecological approaches. This has allowed them to determine one of the most complex signaling networks that control growth and development in response to environmental change.
Chory and her colleagues discovered that plants make and respond to a steroid hormone to control their final size. In a tour de force genetic study, researchers mapped the entire plant hormone signaling system, defining a new paradigm for steroid perception that is distinct from humans.
Her team found that greater than 90 percent of the approximately 30,000 Arabidopsis genes have a peak of expression at a particular time of day, and moreover, the timing changes with the seasons. Farmers, working with scientists, should be able to use this information to predict the consequences of global climate change on agricultural yield.
They determined the mechanism by which a shaded plant can outgrow its neighbor. Since dense planting by farmers leads to a major loss of yield, knowledge of this pathway is already being put to good use.
AB, Biology, Oberlin College, Ohio
PhD, Microbiology, University of Illinois
Postdoctoral Fellow, Harvard Medical School