The roles of membrane transporters in arsenic uptake, translocation and detoxification in plants

Abstract

Arsenic (As) is one of the most toxic environmental contaminants that is ubiquitously distributed in the environment. Millions of people worldwide suffer from As poisoning due to As exposure from drinking water and dietary intake. Reducing As accumulation in food crops is of great importance for food safety and public health. Limiting As accumulation in food crops or phytoremediation of Ascontaminated soil depend on a detailed understanding of As uptake and transport in plants. Plants take up and transport different As species via various membrane transporters that are localized in different tissues or cell types and with different orientations. Many of these transporters are responsible for the uptake and translocation of essential or beneficial nutrients, but can also transport As species inadvertently due to imperfect selectivity. Herein, we summarize the roles of transporters involved in the uptake, transport, accumulation and detoxification of different As species and the regulation mechanisms of these transporters in plants. Potential uses of these transporters for breeding or genetic engineering crops of low As accumulation or plants for phytoremediation are also discussed.

Molecular Interaction and Evolution of Jasmonate Signaling With Transport and Detoxification of Heavy Metals and Metalloids in Plants

“…Plant mineral transporters are critical for the accumulation and detoxification of heavy metal metals and metalloids through uptake, xylem/phloem loading and unloading, as well as sequestration (Sharma et al, 2020;Zhao and Wang, 2020;Deng et al, 2021). Various toxic metal transporters in distinct families have been identified and characterized during the last few decades (Che et al, 2018;Tang and Zhao, 2021). Recently, it has been revealed that jasmonates coordinate the transport systems of the toxic minerals to restrict accumulation and enhance tolerance (Lei et al, 2020b;Mousavi et al, 2020;Verma et al, 2020).…”

“…Plant response to heavy metals and metalloids should be integrated into breeding programs to optimize their growth, development, and metabolism for survival. Although large number of functional proteins involved in the accumulation and detoxification of toxic elements have been identified (Clemens and Ma, 2016;Lindsay and Maathuis, 2017;Lei et al, 2020a;Sharma et al, 2020;Zhao and Wang, 2020;Tang and Zhao, 2021), the signal transmission from mineral stress sensing to the regulation of downstream genes is less known. Regulatory models at molecular levels in various plant species have been proposed based on the systematic transcriptomic and biochemical FIGURE 3 | Jasmonic acids limit the accumulation and enhance the tolerance to the toxic elements by coordinating the transport system, activity of antioxidant enzymes, and chelating capacity in plants.…”

“…Membrane-localized mineral transporters in the cellular and long-distance allocation of minerals play a significant role in the detoxification and accumulation of toxic heavy metals and metalloids in plants (Tomar et al, 2015;Clemens and Ma, 2016;Lindsay and Maathuis, 2017;Yamaji and Ma, 2017;Deng et al, 2019Deng et al, , 2021Hu et al, 2020;Sharma et al, 2020;Zhao and Wang, 2020;Liu et al, 2021;Tang and Zhao, 2021). For example, Arabidopsis (Arabidopsis thaliana) Iron Regulated Transporter 1 (AtIRT1), a members of the ZIP (zinc-regulated transporter) family, is the primary transporter for Cd uptake (Lux et al, 2011), while the translocation of Cd from roots (R) to shoots (SH) is mediated by two root pericycle-localized Heavy Metal ATPases (HMAs), AtHMA2, and AtHMA4 (Hussain et al, 2004;Mills et al, 2005).…”

Lsi2: A black box in plant silicon transport

“…Once again, we might look to the As(III)-transport literature to shed some light. Indeed, OsLsi2 has been demonstrated to be capable of As(III) transport and a crucial component of the xylem-loading process ), but other transporters have been identified in pericycle and xylem parenchyma cells, including a C-type ATP-binding cassette (ABC) transporter, OsABCC7, which plays a more direct role in xylem loading and root-to-shoot translocation of As(III) (Tang et al 2019;Tang and Zhao 2020). It is still unknown if such mechanisms exist for Si.…”

The Role of Membrane Transporters in Plant Growth and Development, and Abiotic Stress Tolerance

“…Over-expression of TaZnF in A. thaliana significantly increased tolerance to heat and cold stress as well as promotes early flowering [16]. Similarly, there are numerous studied in many plant species evidenced the pivotal role of MTs in uptake, sequestration, translocation and detoxification of toxic HMs including cadmium (Cd) [17], chromium (Cr) [18], lead (Pb) [19], As [20], cobalt (Co) and zinc (Zn) [21], for more detail see section 3.…”