Physiological responses and comparative transcriptional profiling of maize roots and leaves under imposition and removal of aluminium toxicity

Abstract

So far, the tolerance mechanisms of plant tolerance to aluminium (Al) toxicity are still controversial. This will require an interdisciplinary approaches integrating genetic, molecular, and physiological investigations. To lay a foundation for studying mechanism of whole maize plant tolerance to Al stress (AS) and growth recovery by removal of Al toxicity (RAT), temporal physiological responses and comparative transcriptional profiling of roots and leaves of maize inbred line YQ7-96 under AS with 0.5 mmol L −1 AlCl 3·6H 2O and RAT were studied. In addition to toxicity towards maize, AS can lead to water deficit effect on whole maize plant. There exists independence of transcriptional response mechanisms between leaves and roots when whole maize plant responds to AS and then undergoes RAT treatment. Amino acid metabolism pathways play a very important role in Al detoxification. There exist some signaling pathways parallel to human's ones, including Wnt, ErbB, TGF-beta and Jak-STAT and the type III secretion system, which probably govern maize response to AS and RAT. The data presented in this study are very helpful to understanding of the Al-tolerant mechanisms of whole maize plant.