NSF grant to fund research on genetics and physiology of corn kernel development

UNIVERSITY PARK, Pa. — A research team in Penn State’s College of Agricultural Sciences has received a grant of nearly $1 million from the U.S. National Science Foundation to fund a novel project investigating the molecular and physiological processes that support corn kernel development.

Corn kernels are a global source of food, animal feed, biofuel, starches/sugars and ingredients in many food products. With the $974,891 grant, the researchers aim to better understand the processes of packaging DNA in the cell nucleus required for the development of endosperm, a part of the seed that stores sugars, starch and proteins. It’s a critical component of a healthy corn kernel and is required for its development, according to team leader Surinder Chopra, professor of maize genetics. He noted that the endosperm of the corn kernel is composed of several functionally unique cell layers that support kernel development.

“This project investigates the metabolic processes of development in one such layer, the basal endosperm transfer layer,” he said, explaining this layer is responsible for moving sugars from the plant to the endosperm.

The project will utilize corn mutants that have basal endosperm transfer layer defects associated with unusual expression of tricarboxylic acid cycle genes and metabolites, which impact plant physiology and stress, Chopra said.

“This proposal will thus characterize metabolic and gene regulatory events that are required to maintain cellular homeostasis — a relatively stable equilibrium — during basal endosperm transfer layer development,” he said.

Cells of the basal endosperm transfer layer are highly specialized and crucial to filling the kernel with nutrients, Debamalya Chatterjee, a postdoctoral scholar who is co-principal investigator on the project, pointed out. He added that the project will investigate the biological processes required for the development of these specialized cells of the basal endosperm transfer layer.

“The knowledge gained from this research could be further applied to understand the development of other layers supporting the embryo and endosperm of the corn kernel, as well as other cereal grains of economic importance,” Chatterjee said.

Chopra suggested that study’s findings may help provide the genetic and epigenetic basis of metabolic processes that are required for the development of a healthy corn kernel, which could inform increased quality and production in the future. Epigenetics refer to when genes’ functions are modified without any change in their DNA sequences, Chopra said, creating silent genes whose traits are not expressed in the organism. A better understanding of what induces gene silencing, and how they impact the organism, could help inform methods to create stress-resilient crops, according to the researchers.

The project will use cutting-edge instruments and expertise available through the Core Facilities of the Penn State Huck Institutes of the Life Sciences, including collaboration with Neela Yennawar, director of the X-Ray Crystallography and Automated Biological Calorimetry facility.

Also, the researchers in Chopra’s lab will work with Natasha Tirko, director of the Master of Biotechnology Degree Program of the Huck Institutes, to organize a program for local high schoolers to gain hands-on laboratory and field exercises to learn about the inheritance of crop traits. The program, called Corn Summer Internships in Gene Silencing, will provide participants the opportunity to use plant phenotypes — observable characteristics resulting from the interaction of plants with their environment — to study what triggers epigenetic gene silencing.

These outreach activities will be in collaboration with Caitlin Teti, director and Carol-Beth Book, education program specialist of the Penn State Office of Science Outreach. This project will also involve Virginia State University faculty members Sarah Witiak and Rafat Siddiqui and their undergraduates, who will participate in research and outreach activities at Penn State.