Phosphate (Pi) is a major macronutriment for plants which have developed different strategies to cope with its relative scarcity. It is also an important key factor controlling the availability of many cations in the soil. We will here try to highlight some of the physiological consequences for plant adaptation to Pi deficiency, with a focus on Pi import and root morphology. Pi uptake relies on the presence of multiple high affinity transporters (PHT1 family) located in the plasma membranes (Nussaume et al., 2011). Multiple steps of transcriptional and post-transcriptional regulations (phosphorylation, degradation) of these transporters were identified illustrating the capacity for plants to tightly control their expression levels in the cells (Misson et al., 2004; Misson et al., 2005; Thibaud et al., 2010; Bayle et al., 2011; Chen et al., 2015). Combining several genetic approaches we have investigated the physiological role of these proteins (Ayadi et al., 2015) and the contribution of specific cell layers to Pi uptake (Kanno et al., 2016). Concerning the root morphology, the Desnos group identified by genetic approches complex signal transduction pathways which modulate the response of the primary roots to Pi/metal balance (Reymond et al., 2006; Svistoonoff et al., 2007; Peret et al., 2014; Balzergue et al., 2017).
References:
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