Scientists Link Key Gene to Response to Sunlight Exposure in Corn
Jennifer Martin, CSREES Staff (202) 720-8188
By Stacy Kish, CSREES Staff
November 13, 2007
Plants, like humans, suffer from increased exposure to the sun's rays. Scientists have discovered a unique feature of genes in corn that are affected by exposure to ultraviolet (UV) radiation. Understanding how UV radiation affects corn at the genetic level will help scientists develop methods and approaches to help plants protect themselves from the harmful effects of UV-B radiation.
As the ozone layer decreases and the amount of UV-B radiation reaching the Earth's surface increases, the ability to breed UV-B tolerant agricultural plants will lessen the harmful impacts on agricultural plant production and sustainability, which is crucial in this crop of agricultural and bioenergy importance. This new knowledge will improve crop growth, production and yield.
Plants utilize sunlight during photosynthesis and, consequentially, are exposed to UV radiation, the same rays responsible for sunburn in humans. UV radiation varies by altitude and season, and the recent decrease in the ozone layer allows an even greater percentage of the rays (specifically the UV-B rays) to reach the Earth's surface. UV radiation damages plant DNA and reduces physiological processes, such as plant growth, reproduction and photosynthesis. Plants adapt to the presence of UV-B, but very little is known about the mechanisms used to sense and respond to UV-B radiation.
Ann E. Stapleton and colleagues at the University of North Carolina at Wilmington and Stanford University exposed growing corn plants to UV-B radiation for different lengths of time over a single day. The time course study allowed the researchers to identify common controls for sets of genes that were affected when corn leaves were exposed to UV-B radiation. The identified genes were also linked to plant behavior and structure.
The identified plant genes provide key information on plant control of gene expression responses to UV-B radiation.
The research is presented in the November issue of Plant Biotechnology Journal.
The USDA's Cooperative State Research, Education, and Extension Service (CSREES) funded this research project through the National Research Initiative (NRI) Plant Biology program. The NRI is the largest peer reviewed, competitive grants program in CSREES. It supports research, education and extension grants that address key problems of national, regional and multi-state importance in sustaining all components of agriculture.
CSREES advances knowledge for agriculture, the environment, human health and well-being, and communities by supporting research, education and extension programs in the Land-Grant University System and other partner organizations. For more information, visit www.csrees.usda.gov.