Model suggests crop yields will decline as the planet warms. Most crops don't tolerate extreme heat and prolonged droughts.
Recently, researchers discovered a gene that helps plants sense heat. Scientists hope their discovery — detailed in a new paper, published Tuesday in the journal Nature Communications — will enable the development of more heat-resistant crop varieties.
"We need plants that can endure warmer temperatures, have a longer time to flower and a longer growth period," co-author Meng Chen said in a news release.
"But, to be able to modify plants' temperature responses, you first have to understand how they work. So, that's why identifying this gene that enables heat response is so important," said Chen, a professor of botany and plant sciences at the University of California, Riverside.
The gene described in the new paper is the second heat-related plant gene discovered by Chen and her research partners. They named the first gene HEMERA.
Plants react quickly to changes in ambient temperature — closing the pores in their leaves to avoid losing too much water, for example.
To find additional heat-related genes, researchers tweaked the genes of a rockcress plant, Arabidopsis, that was bred to be entirely insensitive to temperature.
Based on what scientists learned from finding the HEMERA gene, researchers altered the genome of the rockcress plant until it began reacting to temperature changes. The experiments revealed the new gene, named RCB.
In a followup experiment, scientists silenced HEMERA and RCB expressions and again found themselves with a plant entirely numb to ambient temperature.
"If you knock out either gene, your plant is no longer sensitive to temperature," Chen said.
Both HEMERA and RCB control the expression of an array of gene regulators, all of which are involved in the production and regulation of proteins involved in a plant's response to both temperature and light.
The proteins controlled by HEMERA and RCB are evenly distributed in two different cell components, the nucleus and organelles called chloroplasts.
In future studies, scientists said they plan to investigate the ways these two different parts of the cell coordinate their actions to trigger plant growth, greening and flowering.
The scientists surmise the communication and coordination between a plant cell's nucleus and chloroplasts is mediated by the expression of HEMERA and RCB.
"We were excited to find this second gene," Chen said. "It's a new piece of the puzzle. Once we understand how it all works, we can modify it, and help crops cope better with climate change."
