Plant Peptide Plays a Role in Salt Stress Tolerance

Scientists at the RIKEN Center for Sustainable Resource Science reported their discovery of a hormone-like small protein that helps plants increase their tolerance to excessive salt. The report is published in the Proceedings of the National Academy of Sciences of the USA (PNAS).

They started the study by looking for small proteins linked to salinity tolerance through microarray analysis. Each of the genes that were expressed more under high salinity conditions was overexpressed in transgenic plants and then the transgenic plants were exposed to salinity stress test. Four of the transgenic plants showed better tolerance to salinity compared to the control plants. Then they focused their investigation on AT13, which induced the greatest tolerance to saline conditions.

Further tests showed that levels of the AT13 peptide naturally increased when plants were exposed to salt stress. Thus, the team searched the most important part of the peptide by making pieces of the AtPep3 peptide synthetically. They later found that treating plants with one section of the peptide (AT13-5) was as effective as boosting tolerance through transgenic overexpression of the gene.

"Peptides are natural compounds that are safer than genetically modified plants," said Kentaro Nakaminami, lead researcher of the study. "Additionally, potential supplements made from synthetic peptide fragments will be easy to apply to different species of plants," he added.

Read more from PNAS and SeedQuest.