Researchers examining how the hormone jasmonate works to protect plants and promote their growth have revealed how a transcriptional repressor of the jasmonate signaling pathway makes its way into the nucleus of the plant cell.
They hope the recently published discovery will eventually help farmers experience better crop yields with less use of potentially harmful chemicals.
“This is a small piece of a bigger picture, but it is a very important piece,” said Maeli Melotto, a University of Texas at Arlington assistant professor of biology.
Melotto recently co-authored a paper that advances current understanding of plant defense mechanisms with her collaborator Sheng Yang He and his team at Michigan State University’s Department of Energy Plant Research Laboratory (DOE-PRL). He is a Howard Hughes Medical Institute-Gordon and Betty Moore Foundation investigator. A paper on the collaboration was published online Nov. 19 in the Proceedings of the National Academy of Sciences under the title, “Transcription factor-dependent nuclear import of transcriptional repressor in jasmonate hormone signaling.”
Jasmonate signaling has been a target of intense research because of its important role in maintaining the balance between plant growth and defense. In healthy plants, jasmonates play a role in reproductive development and growth responses. But, when stressors such as herbivorous insects, pathogen attack, or drought, jasmonate signaling shifts to defense-related cellular processes.
The team from UT Arlington and Michigan State focused on the role of jasmonate signaling repressors referred to as JAZ. Specifically, they looked at how JAZ interacts with a major transcription factor called MYC2 and a protein called COI1, which is a receptor necessary for jasmonate signaling.
The researchers discovered that a physical interaction between the repressors and the MYC2 persisted inside the plant cell nucleus, preventing jasmonate-associated gene transcription.
“This tight repression of transcription factors may be important because activation of jasmonate signaling, although important for plant defense against pathogens and insects, is energy-consuming and could lead to growth inhibition – a widely known phenomenon called growth-defense tradeoff,” said He, the Michigan State plant biologist. “In other words, plants have developed a mechanism to tightly repress presumably energy-consuming, jasmonate-mediated defense responses until it becomes necessary, such as upon pathogen and insect attacks.”
The National Institutes of Health, the U.S. Department of Energy, Howard Hughes Medical Institute and the Gordon and Betty Moore Foundation funded the work featured in the recent paper.
Melotto said understanding jasmonate signaling at the molecular level is also vital because some plant pathogens, such as Pseudomonas syringae, have developed ways to mimic the hormone’s action in the cell. This gives them the ability to aggressively colonize plants without activating natural defense mechanisms, she said.
Melotto, who is currently receiving National Institutes of Health funding to examine plant defenses, said the next step in her jasmonate research is to determine which domain of the JAZ protein is responsible for plant innate immunity.
“This is one way to have sustainable agriculture,” Melotto said of the research. “By increasing genetic resistance we could reduce the use of pesticides, decrease crop production costs and promote environmentally friendly farming practices.”
Melotto’s work with Michigan State University is an example of the collaborative research going on at UT Arlington, a comprehensive research institution of more than 33,200 students and more than 2,200 faculty members in the heart of North Texas. Visit www.uta.edu to learn more.
Do you need to use a graphite or talc, with a high rate poncho, if use vacuum seed meter?
Yep, some manufacturers recommend pure talc for their vacuum seed meters and some recommend a blend of talc and graphite. Many with the central fill distribution system are suggesting that they need more lubricant to keep the seed flowing to the row units. The rate of seed treatment applied, the quality of the polymer seed coating, and the size of the seed all seem to have some impact on seed flow and plantability.
==========Not sure that corrupt IL is the place to put grant money but here's the story FWIW......
University to improve crop yield through photosynthesis
University of Illinois | December 12, 2012
The University of Illinois has received a 5-year, $25 million grant from the Bill & Melinda Gates Foundation to improve the photosynthetic properties of key food crops, including rice and cassava.
The project, titled “RIPE – Realizing Increased Photosynthetic Efficiency,” has the potential to benefit farmers around the world by increasing productivity of staple food crops. Illinois research will take place at the Institute for Genomic Biology (IGB), a state-of-the-art facility whose large shared laboratories accommodate multiple groups and encourage cross-discipline interaction.
“This grant will be game changing,” said Stephen Long, project director and Gutgsell Endowed Professor of Crop Sciences and Plant Biology at Illinois. “This project represents a huge effort to determine and apply the mechanisms of photosynthesis that can contribute to meeting the challenge of this century: food security for all.”
Increasing photosynthetic efficiency has not yet been addressed by conventional breeding methods, though it has the potential to increase yields and reduce the use of water and nitrogen. Team members will apply recent advances in photosynthesis research and crop bioengineering to the RIPE project. In addition, computer simulation models of the highly complex photosynthetic system combined with practical engineering will identify the best targets for improving photosynthesis efficiency.
“The U.N. Food and Agricultural Organization predicts that the world will need to increase staple crop yields 70 percent by 2050,” said Long. “The rapid increases that were achieved during the Green Revolution have slowed and will not meet this target. Photosynthesis promises a new area, ripe for exploitation, that will provide part of the yield jump the world needs to maintain food security.”
The U of I, a pioneer in the impact of global change factors on crop plants, will lead the study. The university is home to SoyFACE (Soybean Free Air Concentration Enrichment), an outdoor facility for growing crops under a variety of atmospheric climatic conditions. Research at SoyFACE has offered strong evidence linking increased photosynthesis to consistently higher crop yields over the 10 years of its operation. Illinois is also home to the American Recovery and Reinvestment Act PETROSS program, which is engineering improved photosynthesis into two key U.S. bioenergy crops, sugarcane and sorghum.
Don Ort, associate director of the project and Robert Emerson Professor of Plant Biology at Illinois and USDA–Agricultural Research Service research leader, states “Business-as-usual crop development in the face of accelerating agricultural demand and the challenges of rapid global change will not get the job done. This award invests in unique strengths at Illinois as well as at our collaborating institutions and holds exceptional promise for broad-impact outcomes.” Ort leads the IGB research theme Genomic Ecology of Global Change.
“This grant reflects the historic excellence of photosynthesis research on this campus, and the cutting-edge approaches that have been developed for plant science at the IGB over the past few years by the members of the Genomic Ecology of Global Change and Energy Biosciences research themes,” said IGB Director Gene Robinson.
Illinois will conduct the study through an international collaboration with other leading research institutions as sub-contractors of Illinois, which will initially include the Australian National University, Rothamsted Research (UK), University of Essex (UK), and USDA/ARS.