Ectopic expression of the yeast Mn²⁺ transporter SMF2 enhances tolerance and resistance to cadmium and arsenic in transgenic Arabidopsis

Abstract

Vesicular sequestration is a potential strategy for enhancing plant tolerance to cadmium (Cd) and arsenic (As). In this study, the ectopic overexpression of yeast-derived ScSMF2 in Arabidopsis thaliana was found to enhance the accumulation and tolerance of Cd and As in transgenic plants. ScSMF2 was localized on vacuole membranes and formed puncta structures in plant cells when agro-infiltrated for transient expression. Transgenic Arabidopsis showed less retardation on root elongation and shoot weight and more accumulation of Cd, As (III) and As (V) when cultured on medium containing Cd or As. Overexpression of ScSMF2 promoted accumulation of Cd and arsenic in transgenic Arabidopsis, which were over twice higher than in WT plants when cultured in soil. This study provides insights into the mechanisms involved in the vesicular sequestration of heavy metals in plant and presents a potential strategy for enhancing the phytoremediation capacity of plants toward heavy metals.

NOVELTY STATEMENT

Ectopic overexpression of the yeast Mn²⁺ transporter SMF2 in Arabidopsis thaliana substantially boosts the accumulation and tolerance to Cd and As in plants. This augmentation is attributed to the enhanced efficacy of intracellular vesicle sequestration, thereby bolstering the capacity of plants to sequester and detoxify these toxic heavy metals. This investigation introduces a potential approach for cultivating plants with improved phytoremediation capabilities, thereby advancing eco-friendly and sustainable remediation initiatives against heavy metal pollution.

Keywords:

• Arsenic
• cadmium
• metal transporter
• phytoremediation
• SMF2

Acknowledgments

The authors express their gratitude to Professor Mi Ma from the Institute of Botany, The Chinese Academy of Sciences, for her valuable suggestions and guidance throughout the research. In addition, appreciation is extended to the anonymous reviewers for their insightful comments and suggestions on our manuscript. We would also like to thank TopEdit (www.topeditsci.com) for English language editing of this manuscript.

Disclosure statement

No potential conflicts of interest were reported by the authors.

Additional information

Funding

This research was funded by grants from the National Natural Science Foundation of China (Grant No. 32060498), the Inner Mongolia Autonomous Region Natural Science Foundation (Grant No. 2022LHMS03013 and 2022MS03020) and Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region (Grant No. NJYT23139).