Periodic Reporting for period 1 - RESILIENCE (RESILIENT2: A novel thermosensory module at the interface of temperature and defense signaling)
Reporting period: 2015-09-01 to 2017-08-31
Our initial characterization of res2 mutants suggest that res2 has defective thermosensory response but enhanced defense responses. Further mapping and molecular functional characterization of RES2 would add additional layer of information through which it controls growth and immunity in context to temperature. Because, res2 is defective in thermosensory growth response, we hypothesized that it could be due to defective PIF4 signaling. In fact, results from our study reveals that thermosensory pathway, which is mediated by Phytochrome interacting factor 4 (PIF4), is directly involved in suppressing defense responses at elevated temperatures. We found that PIF4 is necessary for the suppression of elevated temperature mediated suppression of defense responses. Our work might have a direct implication in designing crop plants with increased disease resistance and yield potential under warmer climatic conditions. Indeed, our results suggest that by modulating PIF4 (possibly other PIFs) we could achieve resilient resistance even at elevated temperatures. Moreover, we found that variation in PIF4 signaling could play a key role in balancing growth-defense trade-off in nature. This would further help in understanding the adaptation of plants to particular natural environments. Our future line of research in understanding how RES2 feeds into PIF4 pathway at the molecular levels would shed light on the exact mechanism through which RES2 functions. These findings provide a mechanistic framework for the coordination of growth and immunity in response to the environment, and opens up avenues for development of technologies for crop improvement towards climate resilience.