Long-Distance Signaling of Iron Deficiency in Plants
Iron is an essential nutrient used for many physiological reactions in a whole plant body. A large amount of iron exists in the Earth’s crust, but plants cannot uptake iron from roots efficiently because of the low iron solubility. The uptake and translocation of iron from roots to shoots are strictly controlled in order to maintain homeostasis of cytosol. It has been suggested that long-distance signaling from shoots to roots is involved in the regulation mechanisms of iron uptake. The identification of genes related to iron uptake was made possible because of the rapid development of molecular biology since the 1990s.
In this chapter, we describe the history of the discovery of the iron uptake genes and their regulation factors, and explain the interaction of these factors. Furthermore, we show some models of long-distance signaling which consistently explain the relationship between the phenotype of some mutants and the gene functions involved in iron uptake.
KeywordsIron Nicotianamine Transporter Long-distance signal Iron deficiency
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