Mn-euvering manganese: the role of transporter gene family members in manganese uptake and mobilization in plants

Abstract

Manganese (Mn), an essential trace element, is important for plant health. In plants, Mn serves as a cofactor in essential processes such as photosynthesis, lipid biosynthesis and oxidative stress. Mn deficient plants exhibit decreased growth and yield and are more susceptible to pathogens and damage at freezing temperatures. Mn deficiency is most prominent on alkaline soils with approximately one third of the world's soils being too alkaline for optimal crop production. Despite the importance of Mn in plant development, relatively little is known about how it traffics between plant tissues and into and out of organelles. Several gene transporter families have been implicated in Mn transport in plants. These transporter families include NRAMP (natural resistance associated macrophage protein), YSL (yellow stripe-like), ZIP (zinc regulated transporter/iron-regulated transporter [ZRT/IRT1]-related protein), CAX (cation exchanger), CCX (calcium cation exchangers), CDF/MTP (cation diffusion facilitator/metal tolerance protein), P-type ATPases and VIT (vacuolar iron transporter). A combination of techniques including mutant analysis and Synchrotron X-ray Fluorescence Spectroscopy can assist in identifying essential transporters of Mn. Such knowledge would vastly improve our understanding of plant Mn homeostasis.

Performance of Iron Plaque of Wetland Plants for Regulating Iron, Manganese, and Phosphorus from Agricultural Drainage Water

“…Studies with Lynch and Clair [44], and Socha and Guerinot [45], have shown that Mn deficiency can be caused by multiple factors including high concentrations of other minerals in the soil, such as Fe, Mg, Ca, and P. The results of Ghasemi-Fasaei et al [46] showed that foliar application of Fe on chickpea decreased Mn uptake owing to the antagonistic effect of Fe on translocation of Mn from root to shoot. Similar to Mn, the uptake and translocation of Zn was also inhibited by Fe in the solution [47,48].…”

CAX‐ing a wide net: Cation/H+ transporters in metal remediation and abiotic stress signalling

“…2011a; Socha & Guerinot 2014). Specific CAX1 mutant variants increase metal transport in yeast expression assays while dramatically decreasing Ca 2+ transport (Shigaki et al .…”

The Evolutionarily Conserved Protein PHOTOSYNTHESIS AFFECTED MUTANT71 is Required for Efficient Manganese Uptake at the Thylakoid Membrane in Arabidopsis

“…As outlined above, the physiological impairments in pam71 resulted from depletion of manganese in the thylakoid lumen, and expression of the PAM71 protein in Dpmr1 yeast cells suppressed their Mn 2+ sensitivity (Figure 10). A number of putative Mn 2+ transporters in plants have been described and can be grouped based on the direction of manganese transport either into or out of the cytosol (Socha and Guerinot, 2014). Manganese transport from the cytosol into the vacuole mediated by CATION EXCHANGER2 (CAX2), CAX4, and CAX5 (Hirschi et al, 2000;Cheng et al, 2002;Edmond et al, 2009) or into the prevacuolar and Golgi-like compartment mediated by the Mn 2+ transporter MTP11 (Delhaize et al, 2007;Peiter et al, 2007) presumably also involves a Mn 2+ /H + antiport mechanism in Arabidopsis.…”