A group of non-steroidal anti-inflammatory drugs (NSAIDs) may prove valuable for investigating the molecular mechanisms inherent in plant immunity, according to plant scientists at RIKEN. Their results may also help improve genome-editing techniques for crops.
Many NSAIDs, including aspirin, are derived from a plant defense signaling hormone called salicylic acid. In plants, salicylic-acid levels increase in response to pathogenic attacks from viruses, fungi and bacteria. External treatment with salicylic acid can also boost the immune responses of plants. However, the precise mechanisms underlying salicylic-acid signaling pathways are unclear, partly because the compound plays multiple roles and acts differently in different plants.
Ken Shirasu at the RIKEN Center for Sustainable Resource Science has spent many years studying plant immunity. Back in 1997, he demonstrated that salicylic acid induces immune signaling. When they encounter a pathogen, plants trigger salicylic-acid activity to induce local cell death as a key immunity response.
"Chemical genetics has come a long way since then, and so I decided to return to my initial experiment with my team here at RIKEN," says Shirasu. "We re-established the assay using a cell-culture system of the model plant Arabidopsis."