The Burch-Smith lab had a busy week last week, with two papers published. One was led by former postdoc Elena Ganusova and current graduate student Brandon Reagan, and included important contributions from other graduate students and undergraduate researchers in the lab. Dr. Burch-Smith and her graduate student Jessica Fernandez also published in a collaboration with Dr. Pradeep Kachroo’s group from the University of Kentucky, Lexington.
The first paper, “Chloroplast-to-nucleus retrograde signaling controls intercellular trafficking via plasmodesmata formation”, was published in Philosophical Transactions of the Royal Society B as part of a special issue on retrograde signaling from endosymbiotic organelles. It characterizes the role of the chloroplast in the regulation of intercellular trafficking. The work reveals that different changes in chloroplast RNA processing result in distinct changes in intercellular trafficking. Further, these changes in intercellular trafficking are correlated with changes in plasmodesmal density. While intuitive, evidence for this simple correlation between the number of plasmodesmata and the relative amount of trafficking has been difficult to come by. Collectively, these findings indicate that chloroplasts control plasmodesmata formation as a way for the plant to regulate intercellular trafficking of nutrients and other signaling molecules. The paper can be accessed here: https://royalsocietypublishing.org/doi/10.1098/rstb.2019.0408
The second paper, “The plant cuticle regulates apoplastic transport of salicylic acid during systemic acquired resistance”, was published in the most recent issue of Science Advances. The article highlights the important role that the waxy plant cuticle has in the transport of salicylic acid from local to distal tissues during defense responses to pathogens. Salicylic acid is a major plant defense hormone, and is well known as the active ingredient in aspirin. Another major finding is that an increase in water permeability of the cuticle impairs salicylic acid transport. In summary, the paper highlights the role of salicylic acid as an important mobile signal in whole-plant defense responses. This paper can be found here: https://advances.sciencemag.org/content/6/19/eaaz0478/tab-pdf