Long-Distance Signals Feedback Regulation of Physiological and Molecular Responses Under Iron Deficiency in Rice (Oryza sativa).

Iron (Fe) is an essential micronutrient for plant growth and its accumulation affects the quality of edible plant organs. To investigate the adaptive mechanism of rice grown under iron deficiency, proteins differentially accumulated in leaves and roots under Fe deficiency growth condition were firstly been profiled. The accumulations of seventy-three proteins were detected to be increased or decreased upon iron deficiency, involved in photosynthesis, carbohydrate metabolism, oxidative stress, Adenosine triphosphate (ATP) synthesis, cell growth or signal transduction. Based on the above discovery, two rice cultivars differing in iron accumulation ability in seeds were used to compare the different performance in the corresponding physiological pathway. We found the differential expression of root uptake and shoot remobilization genes in the two cultivars is correlated to the Fe content in roots, shoots, and seeds. Furthermore, long-distance signals generated in rice shoots were involved in regulating the Fe uptake genes. Our results provide a comprehensive way to understand the adaptive mechanism used by rice shoots and roots under iron deficiency.

Schematic presentation of changes in signal transduction, carbohydrate transport, photooxidative damage and respiration of rice under iron deficiency