Cadmium uptake and membrane transport in roots of hyperaccumulator Amaranthus hypochondriacus L

Mengxuan Han; Habib Ullah; Huan Yang; Guo Yu; Shaohong You; Jie Liu; Baoliang Chen; Asfandyar Shahab; Vasileios Antoniadis; Sabry M Shaheen; Jörg Rinklebe

doi:10.1016/j.envpol.2023.121846

Cadmium uptake and membrane transport in roots of hyperaccumulator Amaranthus hypochondriacus L

Environ Pollut. 2023 Aug 15;331(Pt 1):121846. doi: 10.1016/j.envpol.2023.121846. Epub 2023 May 19.

Authors

Mengxuan Han¹, Habib Ullah², Huan Yang³, Guo Yu⁴, Shaohong You⁵, Jie Liu⁶, Baoliang Chen⁷, Asfandyar Shahab⁸, Vasileios Antoniadis⁹, Sabry M Shaheen¹⁰, Jörg Rinklebe¹¹

Affiliations

¹ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China. Electronic address: 244633656@qq.com.
² Innovation Center of Yangtze River Delta, Zhejiang University, Hangzhou, Zhejiang, China. Electronic address: habib901@zju.edu.cn.
³ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China. Electronic address: 945183472@qq.com.
⁴ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China. Electronic address: yuguo@glut.edu.cn.
⁵ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China. Electronic address: youshaohong@glut.edu.cn.
⁶ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China. Electronic address: liujie@glut.edu.cn.
⁷ Innovation Center of Yangtze River Delta, Zhejiang University, Hangzhou, Zhejiang, China.
⁸ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China. Electronic address: 2017022@glut.edu.cn.
⁹ Department of Agriculture Crop Production and Rural Environment, University of Thessaly, Greece. Electronic address: antoniadis@uth.gr.
¹⁰ University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, Wuppertal, Germany; King Abdulaziz University, Faculty of Meteorology, Environment, and Arid Land Agriculture, Department of Arid Land Agriculture, 21589 Jeddah, Saudi Arabia; University of Kafrelsheikh, Faculty of Agriculture, Department of Soil and Water Sciences, 33516, Kafr El-Sheikh, Egypt. Electronic address: shaheen@uni-wuppertal.de.
¹¹ University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, Wuppertal, Germany. Electronic address: rinklebe@uni-wuppertal.de.

PMID: 37211225
DOI: 10.1016/j.envpol.2023.121846

Abstract

Hyperaccumulator Amaranthus hypochondriacus L. has huge potential in the remediation of cadmium (Cd)-contaminated soils and is necessary to understand the mechanism of Cd uptake by the roots. In this study, the mechanism of Cd uptake into the root of A. hypochondriacus was investigated using the non-invasive micro-test technology (NMT) by analyzing the rate of Cd²⁺ fluxes at different regions of the root tip; also we assessed the impact of different channel blockers and inhibitors on the Cd accumulation in the roots, the real-time Cd²⁺ fluxes, and the distribution of Cd along the roots. The results showed that the Cd²⁺ influx was greater near the root tip (within 100 μm of the tip). All the inhibitors, ion-channel blockers, and metal cations had different degrees of inhibition on the absorption of Cd in the roots of A. hypochondriacus. The net Cd²⁺ flux in the roots was significantly decreased by the Ca²⁺ channel blockers lanthanum chloride (LaCl₃) by up to 96% and verapamil by up to 93%; as for the K⁺ channel blocker tetraethylammonium (TEA), it also caused a 68%-reduction on the net Cd²⁺ flux in the roots. Therefore, we infer that the uptake by A. hypochondriacus roots is mainly through the Ca²⁺ channels. The Cd absorption mechanism appears to be related to the synthesis of plasma membrane P-type ATPase and phytochelatin (PC), which is reflected by the inhibition of Ca²⁺ upon addition of inorganic metal cations. In conclusion, access of Cd ions into the roots of A. hypochondriacus is achieved through various ion channels, with the most important being the Ca²⁺ channel. This study will further enhance the literature regarding Cd uptake and pathways of membrane transport in roots of Cd hyperaccumulators.

Keywords: Amaranthus hypochondriacus L.; Cd uptake; Cd(2+) channel; Hyperaccumulator; Non-invasive micro-test technology; Uptake mechanisms.

MeSH terms

Amaranthus* / metabolism
Biodegradation, Environmental
Cadmium / analysis
Metals / metabolism
Plant Roots / metabolism
Soil Pollutants* / analysis

Substances

Cadmium
Soil Pollutants
Metals