How plants cope with stress and damage?

Washington DC New research has found that plants use chloroplasttonucleus communication to cope with stress or damage caused by different sources Plants regulate the genes expression via this communication that helps them to deal with various damage and stress The study published in the Proceedings of the National Academy of Sciences PNAS could help biologists breed plants that can better withstand environmental stressorsAccording to the research a gene that integrates numerous chloroplasttonucleus retrograde signalling pathways GUN1 also plays an important role in how proteins are made in damaged chloroplasts which provides new insight into how plants respond to stressClimate change holds the potential to affect our food system dramatically When plants are stressed like in a drought they produce lower crop yields If we understand how plants respond to stress then perhaps we can develop a way to increase their resistance and keep food production high said Joanne Chory senior author of the paperIn plant cells structures called chloroplasts convert energy from sunlight into chemical energy photosynthesis Normally the nucleus of the cell transmits information to the chloroplasts to maintain steady energy productionHowever in a stressful environment chloroplasts send an alarm back to the cell nucleus using retrograde signalling creating a chloroplasttonucleus communication feedback loop This SOS prompts a response that helps regulate gene expression in the chloroplasts and the nucleus to optimise energy production from sunlightPreviously the Chory lab identified a group of genes including GUN1 that influence other genes expression in the cell when the plant experiences stress GUN1 accumulates under stressful conditions but the exact molecular function of GUN1 has been difficult to decipher until nowPlants often experience environmental stressors so there must be a chloroplasttonucleus communication pathway that helps the plant know when to conserve energy when an injury occurs GUN1 turns out to play a big role in this said Xiaobo Zhao first author of the studyTo understand how GUN1 regulates chloroplasttonucleus communication the scientists observed plants with functional and nonfunctional GUN1 under pharmacological treatments that could damage chloroplastsIn plants without GUN1 gene expression changed as did RNA editing in chloroplasts RNA editing is a modification of the RNA that changes the identity of nucleotides so that the information in the mature RNA differs from that defined in the genome altering the instructions for making proteins Some areas of RNA had more editing and other locations had less editing suggesting that GUN1 plays a role in regulating chloroplast RNA editingAfter further analysis the team unexpectedly found that GUN1 partners with another protein MORF2 an essential component of the plant RNA editing complex to affect the efficiency of RNA editing during chloroplasttonucleus communication in damaged chloroplastsGreater activity of MORF2 led to widespread editing changes as well as defects in chloroplast and leaf development even under normal growth conditions During periods of stress and injury MORF2 overproduction also led to a disruption of chloroplasttonucleus communicationTaken together these findings suggest a possible link between chloroplasttonucleus communication and chloroplast RNA editing which are important regulatory functions for flowering plants especially during stress said ChoryNext the researchers plan to examine the mechanism of how the RNA editing changes in chloroplasts activate signals that can be relayed to the nucleus and how these modifications alter the ability of the plant to respond to stressCatch up on all the latest Crime National International and Hatke news here Also download the new midday Android and iOS apps to get latest updates