Novel PvACR3;2 and PvACR3;3 genes from arsenic-hyperaccumulator Pteris vittata and their roles in manipulating plant arsenic accumulation

• Published in: Journal of hazardous materials 2021-08, Vol.415, p.125647, Article 125647
• Main Authors: Chen, Jun-Xiu, Cao, Yue, Yan, Xiangjuan, Chen, Yanshan, Ma, Lena Q.
• Format: Article
• Language: English
• Subjects: Arsenic - toxicity; Biodegradation, Environmental; Efflux and translocation; Food safety; Nicotiana - genetics; Phytoremediation; Plant Roots - genetics; Pteris - genetics; sequestration; Soil Pollutants; Tobacco plant; Yeast
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.125647

Arsenite (AsIII) antiporter ACR3 is crucial for arsenic (As) translocation and sequestration in As-hyperaccumulator Pteris vittata, which has potential for phytoremediation of As-contaminated soils. In this study, two new ACR3 genes PvACR3;2 and PvACR3;3 were cloned from P. vittata and studied in model organism yeast (Saccharomyces cerevisiae) and model plant tobacco (Nicotiana tabacum). Both ACR3s mediated AsIII efflux in yeast, decreasing its As accumulation and enhancing its As tolerance. In addition, PvACR3;2 and PvACR3;3 were expressed in tobacco plant. Localized on the plasma membrane, PvACR3;2 mediated both AsIII translocation to the shoots and AsIII efflux from the roots in tobacco, resulting in 203 − 258% increase in shoot As after exposing to 5 μM AsIII under hydroponics. In comparison, localized to the vacuolar membrane, PvACR3;3 sequestrated AsIII in tobacco root vacuoles, leading to 18 − 20% higher As in the roots and 15 − 36% lower As in the shoots. Further, based on qRT-PCR, both genes were mainly expressed in P. vittata fronds, indicating PvACR3;2 and PvACR3;3 may play roles in AsIII translocation and sequestration in the fronds. This study provides not only new insights into the functions of new ACR3 genes in P. vittata, but also important gene resources for manipulating As accumulation in plants for phytoremediation and food safety. [Display omitted] •Two new ACR3 genes (PvACR3;2 and PvACR3;3) were identified from P. vittata.•PvACR3;2 is the most efficient arsenite transporter among four ACR3s in P. vittata.•PvACR3;2 localized on the plasma membrane and mediated As translocation in tobacco.•PvACR3;3 localized on the vacuolar membrane and sequestrated As into vacuoles.•This study provides genes to manipulate plant As for phytoremediation and food safety.