Control of Zn uptake in Arabidopsis halleri: a balance between Zn and Fe
نویسندگان
چکیده
Zinc (Zn) is an essential plant micronutrient but is toxic in excess. To cope with excess Zn, plant species possess a strict metal homeostasis mechanism. The Zn hyperaccumulator Arabidopsis halleri has developed various adaptive mechanisms involving uptake, chelation, translocation and sequestration of Zn. In this mini review, we broadly discuss the different Zn tolerance mechanisms and then focus on controlled Zn uptake in A. halleri. Members of the ZRT/IRT-like protein (ZIP) family of metal transporters are mainly regulated by Zn and are involved in Zn uptake. A few members of the ZIP family, such as IRT1 and IRT2, are regulated by iron (Fe) and can transport multi-metals, including Zn, Fe, Mn, Cd, and Co. This mini-review also discusses the differential expression of multiple metal ZIP transporters in A. halleri and A. thaliana, a non-hyperaccumulator, with Zn exposure as well as Fe deficiency and their role in controlled Zn uptake and tolerance.
منابع مشابه
Nicotianamine secretion for zinc excess tolerance.
Plants acquire micronutrients such as iron (Fe), zinc (Zn), manganese, or copper from soil. These micronutrients are often not readily available and they need to be mobilized to the proper free ionic form in order to be taken up by plant roots. Perhaps the only exception to this is the uptake of Fe by grasses, which have evolved a so-called strategy II uptake mechanism that involves the secreti...
متن کاملZinc-dependent global transcriptional control, transcriptional deregulation, and higher gene copy number for genes in metal homeostasis of the hyperaccumulator Arabidopsis halleri.
The metal hyperaccumulator Arabidopsis halleri exhibits naturally selected zinc (Zn) and cadmium (Cd) hypertolerance and accumulates extraordinarily high Zn concentrations in its leaves. With these extreme physiological traits, A. halleri phylogenetically belongs to the sister clade of Arabidopsis thaliana. Using a combination of genome-wide cross species microarray analysis and real-time rever...
متن کاملZinc distribution and speciation in Arabidopsis halleri x Arabidopsis lyrata progenies presenting various zinc accumulation capacities.
The purpose of this study was to investigate the relationship between the chemical form and localization of zinc (Zn) in plant leaves and their Zn accumulation capacity. An interspecific cross between Arabidopsis halleri sp. halleri and Arabidopsis lyrata sp. petrea segregating for Zn accumulation was used. Zinc (Zn) speciation and Zn distribution in the leaves of the parent plants and of selec...
متن کاملMetal accumulation in tobacco expressing Arabidopsis halleri metal hyperaccumulation gene depends on external supply
Engineering enhanced transport of zinc to the aerial parts of plants is a major goal in bio-fortification. In Arabidopsis halleri, high constitutive expression of the AhHMA4 gene encoding a metal pump of the P(1B)-ATPase family is necessary for both Zn hyperaccumulation and the full extent of Zn and Cd hypertolerance that are characteristic of this species. In this study, an AhHMA4 cDNA was int...
متن کاملNicotianamine in zinc and iron homeostasis.
Transition metals such as Fe, Zn, and Cu are essential to plants but toxic in excess, and their accumulation is tightly regulated (Palmer and Guerinot, 2009). Offering exciting possibilities for applications such as bioremediation of contaminated sites and biofortification against nutritional deficiencies (e.g., of Zn; Palmgren et al., 2008), the molecular mechanisms of metal homeostasis are be...
متن کامل