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Magnetoreception in Plants

FIGURE 5.8 Te GMF infuences the photoreceptor activation and signaling in Arabidopsis. Under blue light, the

GMF regulation of gene expression is mainly dependent on cryptochromes, whose activation is enhanced in terms

of increased cry1 phosphorylation and cry2 degradation. By contrast, phot1 phosphorylation is not afected by the

GMF. Under red light, cry1 and phot1 in their inactive form contribute to the GMF-dependent increase in phyB

activation and the GMF-dependent decrease in phyA: phyB degradation is indeed enhanced by the GMF, whereas

that of phyA is enhanced under NNMF conditions. (From Agliassa et al. (2018b).)

is not afected. Accordingly, Fe uptake genes were induced in the roots of NNMF-exposed plants and

the root Fe reductase activity was afected by transferring GMF-exposed plant to NNMF condition.

Under Fe defciency, NNMF-exposed plants displayed a limitation in the activation of Fe-defciency

induced genes. Such an efect was associated with the strong accumulation of Zn and Cu observed under

NNMF conditions (Islam et al., 2020a). Overall, these results provide evidence on the important role

of the GMF on the iron uptake efciency of plants and the importance of such fndings is also associ­

ated to the variability of the GMF with latitude as well as global GMF inversions during life evolution

(Mafei, 2014). Te importance of the GMF on metals (e.g., Fe) uptake might be also linked to the evolu­

tion of Strategy I (Fe reductive-mechanism) and II (non-reductive mechanism) mechanisms in plants.

Considering the importance of MF variations in diferent environments and in future space exploration

where plants might experience MF conditions diferent from the GMF, our results stress the importance

to deepen the investigation on the efect of MF on plant nutrients homeostasis in order to understand

how magnetoreception occurs in plants and in turn how nutrients availability changes depend on GMF

fuctuating values.

In the presence of light, the lipid content (fatty acids and surface alkanes, SA) and mineral nutri­

ents of Arabidopsis were also afected by changes in MF. A progressive increase of SA with carbon

numbers between 21 and 28 was found in plants exposed to NNMF from bolting to fowering devel­

opmental stages, whereas the content of some fatty acids signifcantly increased in rosette, bolting,