UNL plant researchers publish finding on enzyme, drought connection

A better understanding of how plants tolerate drought could result from research by University of Nebraska-Lincoln scientists.

A paper in this week's Proceedings of the National Academies of Sciences, with biologist Heriberto Cerutti as the senior author, announced the discovery of a new enzyme involved in gene regulation in response to environmental stresses. The enzyme, a kinase, modifies chromatin, a dynamic network of interacting DNA, RNA and proteins in the nuclei of cells, and affects gene expression to enable cells to better tolerate environmental adversity. It is also involved in the inheritance of gene expression states by daughter cells.

Cerutti, an associate professor of biological sciences, said the discovery is significant because the enzyme, identified in an algal model system, is also present in plants and could contribute to improving their drought-tolerance. "It's a new component of the gene regulatory network, but I don't think that the actual significance of the discovery will be known for a few years," he said. "If it does what we think it might, it's going to be important."

Other researchers are J. Armando Casas-Mollano, Byeong-ryool Jeong and Jinping Xu, all associated with the university's Center for Plant Science Innovation, and Hideaki Moriyama, a UNL chemistry professor.

The research is part of a nano-enhanced epigenetics grant the National Science Foundation awarded to the Nebraska Experimental Program to Stimulate Competitive Research. The three-year, $9 million grant received last fall will allow UNL to lead research by UNL, the University of Nebraska Medical Center and Creighton University scientists to better understand gene expression and regulation.

Cerutti said Nebraska's research on chromatin is cutting-edge. Chromatin's role in defining gene expression and the modulation of these processes by environmental factors represent key unknowns that need to be addressed to understand how complex biological systems function.

In December 2006, Cerutti's lab published research from the UNL Center for Plant Science Innovation that expanded understanding of RNA interference -- a process that silences genes and holds promise in combating disease. Cerutti's team reported in the journal Science the identification of a novel gene, in the single-cell alga Chlamydomonas reinhardtii, that is required for RNA interference. The new enzyme discovery also involves Chlamydomonas reinhardtii.