A Major Latex Protein-Encoding Gene from () Contributes to Defense Responses to Salt and Cadmium Stress.

Heavy metal pollution and soil salinization harm human health and the environment. Phytoremediation is a widely accepted soil decontamination method, with woody plants being particularly effective due to their large biomass and extensive root systems. In this study, we identified and cloned from and demonstrated its role in mitigating salt and cadmium stress. expression was up-regulated under both stress conditions, and its overexpression in tobacco enhanced resistance to these stresses, albeit through distinct mechanisms. Transgenic plants exhibited increased Cd uptake and a higher biomass, alleviating Cd-induced growth inhibition. Additionally, boosted proline content, chlorophyll levels, and antioxidative enzyme activities (POD, SOD) under Cd stress, likely by protecting cells from oxidative damage. Expression analysis revealed that down-regulated the cadmium transporter while up-regulating (another cadmium transporter) and potassium channels ( and ), suggesting its role in modulating K and Cd homeostasis. These findings indicate that enhances tobacco resistance to salt and cadmium stress, particularly the latter. This study is the first to elucidate the function of poplar family genes under salt and cadmium stress, advancing our understanding of gene roles in heavy metal stress and offering new insights for remediating salinized and heavy metal-contaminated soils.