FAYETTEVILLE, Ark. — Plant pathologist Clemencia M. Rojas received a $900,000 National Science Foundation CAREER Award that will help support her investigation of the biological warfare waged between plants and pathogenic bacteria.

CAREER is the NSF's Faculty Early Career Development Program, one of the Foundation's most prestigious awards, according to information from the NSF. It supports early-career faculty who serve as role models in research and education to advance both their research and educational goals.

"The research that will be pursued in Dr. Rojas' CAREER Award is a great example of the important and innovative research our faculty are conducting across the university," said Jim Coleman, provost and executive vice chancellor for academic affairs.

"Additionally, receiving such a competitive award reflects the high level of respect her peers have for the impact of her previous work and the potential importance and the quality of the proposed research project," Coleman said. 

Rojas, assistant professor of plant pathology for the University of Arkansas System Division of Agriculture and the U of A's Dale Bumpers College of Agricultural, Food and Life Sciences, studies the molecular and cellular interactions between bacterial pathogens and plants to dissect how bacterial pathogens cause disease and how plants fight those pathogens.

Rojas plans to integrate her research program with her teaching by recruiting undergraduate students to help her probe how the myriad proteins activated in both plants and bacteria contribute to either infection or defense.

Researching Defenses

Rojas said plants can detect when a pathogen is trying to infect them and they respond by activating multiple defenses to restrict pathogen proliferation and prevent tissue damage. Among those defenses are the fortification of the cell walls against the intrusion of the pathogen and release of antimicrobials to fight back.

"This is very clever," Rojas said, "because the cell wall is the first point of contact by the pathogen."

Bacterial pathogens, in turn, detect the plant's defenses and begin injecting proteins into the plant that interfere with the plant's defense responses.

The goals are simple — the pathogen needs to get into the plant in order to reproduce and the plant needs to keep it out to remain healthy.

"It's like they know what they're doing," Rojas said.

The pawns in this biological game of chess are the proteins that take offensive or defensive actions. There are perhaps hundreds of specialized proteins that throw themselves against the cellular bulwarks.

"It's a scaffolding of proteins that build up in combinations to do a job on both sides," Rojas said.

Investigation Inside the Cells

In her research for the Arkansas Agricultural Experiment Station and the University of Arkansas, Rojas uses the model plant Arabidopsis thaliana, a commonly used plant because its genetics are well defined. She can genetically modify plants to generate new versions of proteins tagged with fluorescent markers to see inside living cells and explore how these proteins respond to pathogens.

Rojas is also using two versions of the bacterial pathogen Pseudomonas syringae— pathovar tomato, which can damage Arabadopsis, and pathovar tabaci, which does not. She uses pathovar tomato to study the actions of the bacteria while it is attacking a host plant. The pathovar tabaci, which does not naturally attack Arabadopsis, helps her understand how the plant fights the pathogen.

Rojas said her work is basic science and, therefore, does not have immediate practical application. However, "poking and probing at this basic level leads to discoveries that provide us a better base of knowledge," Rojas said.

That foundation of knowledge is used by other scientists to develop new technologies to protect America's and the world's food supply. Rojas said. "Truly understanding how cells work is worth the effort."

But it's a massive effort. "We have found a bunch of proteins and we need to figure out what they do," Rojas said. "We need an army of researchers."

Adding Academics

That's where the education side of Rojas' CAREER plan connects.

Rojas said she plans to recruit undergraduate students from her Bumpers College classes into her research army. Mentoring two undergraduate students at a time, Rojas said she would like each to investigate a single protein. "You pick a protein, you pick a protein," she said.

The students would have to read the research literature, develop hypotheses and design experiments to test them.

"I hope to identify talented and motivated students to join in the research and discovery," Rojas said.

Undergraduate students will have the opportunity to contribute to important research that will have an impact on the future of agricultural production of food and fiber, Rojas said. Her hope is that some of them will choose a career in science.

"Through research and teaching, I can pass on a legacy to a future generation of researchers," Rojas said.

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uark.edu. Follow us on Twitter at @ArkAgResearchand Instagram at ArkAgResearch.

For more information about Bumpers College, visit the college website, and follow us on Twitter at @BumpersCollege and Instagram at BumpersCollege.

About the Dale Bumpers College of Agricultural, Food and Life Sciences: Bumpers College provides life-changing opportunities to position and prepare graduates who will be leaders in the businesses associated with foods, family, the environment, agriculture, sustainability and human quality of life; and who will be first-choice candidates of employers looking for leaders, innovators, policy makers and entrepreneurs. The college is named for Dale Bumpers, former Arkansas governor and longtime U.S. senator who made the state prominent in national and international agriculture.

About the Division of Agriculture: The University of Arkansas System Division of Agriculture's mission is to strengthen agriculture, communities, and families by connecting trusted research to the adoption of best practices. Through the Agricultural Experiment Station and the Cooperative Extension Service, the Division of Agriculture conducts research and extension work within the nation's historic land grant education system.

The Division of Agriculture is one of 20 entities within the University of Arkansas System. It has offices in all 75 counties in Arkansas and faculty on five system campuses.

The University of Arkansas System Division of Agriculture offers all its Extension and Research programs to all eligible persons without regard to race, color, sex, gender identity, sexual orientation, national origin, religion, age, disability, marital or veteran status, genetic information, or any other legally protected status, and is an Affirmative Action/Equal Opportunity Employer.