Molecular identification of tobacco NtAMT1.3 that mediated ammonium root-influx with high affinity and improved plant growth on ammonium when overexpressed in Arabidopsis and tobacco
Copyright © 2017 Elsevier B.V. All rights reserved.
| Publié dans: | Plant science : an international journal of experimental plant biology. - 1985. - 264(2017) vom: 15. Nov., Seite 102-111 |
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| Auteur principal: | |
| Autres auteurs: | , , , , , , , , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2017
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| Accès à la collection: | Plant science : an international journal of experimental plant biology |
| Sujets: | Journal Article Active ammonium transporter Ammonium uptake Arabidopsis qko-mutant Nitrogen use Overexpression Tobacco Yeast complementation Ammonium Compounds Cation Transport Proteins plus... |
| Résumé: | Copyright © 2017 Elsevier B.V. All rights reserved. Although biological functions of ammonium (NH4+) transporters (AMTs) have been intensively studied in many plant species, little is known about molecular bases responsible for NH4+ movement in tobacco. Here, we reported the identification and functional characterization of a putative NH4+ transporter NtAMT1.3 from tobacco (Nicotiana tabacum). Analysis in silico showed that NtAMT1.3 encoded an integral membrane protein containing 464 amino acid residues and exhibiting 10 predicted transmembrane α-helices. Heterologous functionality study demonstrated that NtAMT1.3 expression facilitated NH4+ entry across plasma membrane of NH4+-uptake defective yeast and Arabidopsis qko mutant, allowing a restored growth of both yeast and Arabidopsis mutant on low NH4+. qPCR assay revealed that NtAMT1.3 was expressed in both roots and leaves and significantly up-regulated by nitrogen starvation and resupply of its putative substrate NH4+ and even nitrate, suggesting that NtAMT1.3 should represent a nitrogen-responsive gene. Critically, constitutive overexpression of NtAMT1.3 in tobacco per se improved obviously the growth of transgenic plants on NH4+ and enhanced leaf nitrogen (15% more) accumulation, consistent with observation of 35% more NH4+ uptake by the roots of transgenic lines in 20min root-influx test. Together with data showing its plasma membrane localization and saturated transport nature with Km of about 50μM for NH4+, we suggest that NtAMT1.3 acts an active NH4+ transporter that plays a significant role in NH4+ acquisition and utilization in tobacco |
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| Description: | Date Completed 26.03.2018 Date Revised 13.12.2023 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1873-2259 |
| DOI: | 10.1016/j.plantsci.2017.09.001 |