Abstract
Zinc (Zn) is an essential micronutrient for plants and humans. Nearly 50% of the agriculture soils of world are Zn-deficient. The low availability of Zn reduces the yield and quality of the crops. The zinc-regulated, iron-regulated transporter-like proteins (ZIP) family and iron-regulated transporters (IRTs) are involved in cellular uptake of Zn, its intracellular trafficking and detoxification in plants. In addition to Zn, ZIP family transporters also transport other divalent metal cations (such as Cd2+, Fe2+, and Cu2+). ZIP transporters play a crucial role in biofortification of grains with Zn. Only a very limited information is available on structural features and mechanism of Zn transport of plant ZIP family transporters. In this article, we present a detailed account on structure, function, regulations and phylogenetic relationships of plant ZIP transporters. We give an insight to structure of plant ZIPs through homology modeling and multiple sequence alignment with Bordetella bronchiseptica ZIP (BbZIP) protein whose crystal structure has been solved recently. We also provide details on ZIP transporter genes identified and characterized in rice and other plants till date. Functional characterization of plant ZIP transporters will help for the better crop yield and human health in future.
Highlights
In agriculture, the low availability of nutrients has reduced the crop production
The metal binding and transport residues of OsZIP13, OsZIP16, and ZmZIP6 are more conserved with Bordetella bronchiseptica ZIP (BbZIP) compared to other plant ZIPs. These variations indicated that plant ZIP transporters may have partially overlapping but distinct metal transport mechanism compared to BbZIP as some of the residues involved in metal binding and transport are not conserved in plant ZIPs
In order to gain more insights to the structure of plant ZIP transporters, we have modeled some of the plant ZIP transporters by homology modeling using BbZIP (PDB Id: 5TSA) as a template with Zn2+ as a ligand
Summary
The low availability of nutrients has reduced the crop production. The optimal supply of micro-nutrients in soil solutions is vital for normal agriculture production. Expect AtZIP2 (Ala224), AtZIP11 (Ala216), OsZIP1 (Ala243), and OsZIP2 (Ala248), other plants ZIP transporter proteins possess conserved Gly212 of BbZIP Another interesting observation is that metal-binding site residues such as Asn178, Pro180, and Pro210 are conserved only with OsZIP13, FIGURE 1 | Multiple sequence alignment of Bordetella bronchiseptica ZIP (BbZIP), Arabidopsis (AtZIP), rice (OsZIP), and maize (ZmZIP) transporters. This large information is helpful for understanding the expression pattern of Zn transporters, their localization and metal homeostasis in other crops Apart from these reports we need further studies on the biofortification of rice with Zn in order to increase the FIGURE 5 | Expression of ZIP transporter genes in different parts of rice (A), maize (B), and wheat (C).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
