On November 21st, The Plant Cell published a research paper entitled “Phosphatidic acid directly regulates PINOID-dependent phosphorylation and activation of the PIN-FORMED 2 auxin efflux transporter in response to salt stress” completed by Professor Wenhua Zhang’s team of NAU’s College of Life Science. This study revealed the molecular mechanism of plant cell membrane lipids in response to salt stress via regulating auxin signaling.
Soil salinity is becoming more and more serious worldwide, which threatens crops growth and development, yield, and quality.Improving crop salt tolerance is one of the essential strategy to improve global food production.Systematic and in-depth analysis of plant molecular networks responding to salt stress is vital for the improvement of crop salt tolerance. Professor Wenhua Zhang’s team found that,Phospholipase D (PLD)and its product phosphatidic acid (PA) are important regulators in plant resistance against external stresses.In this study, they found that, under salt stress, PLDα1 and PLDδ were activated, and hydrolyzed substrate PC/PE (phosphatidylcholine/phosphatidylethamolamine) to produce signal molecule PA which bound to and activated PID (PINOID,AGCVIII protein family) phosphorylation of PIN2 (auxin efflux transport protein), resulting in improvement of the auxin transport activity of PIN2, which promoted the redistribution of auxin in root tips and maintained plant growth under salt stress.Previous studies from the team showed that PA regulated a number of important proteins, such as NADPH oxidase RbohD, MAPK6 kinase, and microtubule-binding protein MAP65-1, suggesting that PA widely functions in plan’s response to stresses (Zhang et al., Plant Cell 2009; Yu et al., New Phytology 2010；Zhang et al., Plant Cell 2012).
Working model for PA regulation of auxin signaling and plant’s response to salt stress
The first author of the paper is Peipei Wang, a doctoral student from College of Life Science; the corresponding author is Qun Zhang, an associate professor from College of Life Science. Prof.Wenhua Zhang, associate Prof. Wen Jing, Dr. Like Shen, Dr. Yana Qu, and Prof. Xuanwei from College of Resource and Environmental Sciences also participated in this research.The research is funded by the National Natural Science Foundation of China, the Fundamental Research Funds for the Central Universities, the Natural Science Foundation of Jiangsu Province and the Advantages of disciplines in colleges and universities in Jiangsu Province.