A team of researchers has pinpointed some of the mechanisms used by plants to cope with drought conditions. The discovery of the specific genes and proteins involved may help plant breeders develop crops better suited to changing conditions brought on by global warming. The details were just published in the journal Science.
Climate change is leading to global temperature increases and drought conditions in many areas. This growing problem has prompted plant breeders to begin developing new crop varieties that are more tolerant of environmental stress. Although scientists have known the signs of dehydration in plants, the actual molecular mechanisms were unknown. Identifying the genes responsible for responding to water scarcity could lead to the design of water-efficient crop plants.
Previous studies had already showed that when plants are faced with drought conditions, their roots produce a hormone called abscisic acid. Researchers from the Salk Institute for Biological Studies exposed Arabidopsis thaliana (a common model species in scientific research) plants to the hormone in order to track any molecular changes. The team was able to map out the genes that became activated or inactivated in response to abscisic acid.
The researchers were able to identify a number of genes and complex pathways involved in the plants’ response to the stress hormone. The team found 21 transcription factors, proteins that bind to specific DNA sequences in order to help control gene expression. These proteins can turn genes on or off and influence the regulation of pathways involving environmental stress. Mapping out these pathways allows researchers to understand how different genes and proteins interact.
The team’s findings provide new insights into the complex chemical pathways that are triggered in response to abscisic acid, a hormone produced by dehydrated plants. Understanding how regulatory proteins affect gene expression may eventually lead to the development of drought-resistant plants. Studies like this become critical as climate change pushes the stress limits of our current crop species.
Song et al. A transcription factor hierarchy defines an environmental stress response network. Science (2016).