Stable expression of bacterial transporter ArsB attached to SNARE molecule enhances arsenic accumulation in <i>Arabidopsis</i>

Acute and chronic arsenic (As) toxicity is a global health issue affecting millions of people, which leads to inactivation of over 200 enzymes, particularly those involved in cellular energy pathways and DNA synthesis and repair. The fern <i>Pteris vittata</i> acts as a hyperaccumulator of As and may be useful for phytoremediation to reduce disposal risks by utilizing metal-enriched plant biomass in energy and metal recovery. However, these ferns grow in limited environments and its transplantation and transport can be challenging. Therefore, we generated a transgenic <i>Arabidopsis</i> plant as a seed plant model, capable of accumulating As in their vacuole lumen. This was achieved by transforming the As-resistant bacterial As transporter, ArsB, via fusion with a organelle-targeting signal to the vacuolar membrane, N-ethyl-maleimide-sensitive factor attachment protein receptors (SNAREs) protein, VAMP711. In this study, we developed the iVenus assay as a method for detecting whether the N- or C-terminus of a membrane protein is located on the cytoplasmic or exoplasmic side, and from the result of the iVenus assay, we generated the transgenic plant introduced N-terminal end of ArsB with VAMP711, localized to the central vacuolar membrane to accumulate As in the shoot and differentiation zone of root.