Biology subjects

Kiyono, M.

Publications and source records attributed to Kiyono, M..

3 recordsLinked to original sources

bioRxiv2025

Feasibility of an eDNA-based educational program for high school students

O_LIEnvironmental education plays a crucial role in raising public awareness of ecosystem conservation. Environmental DNA (eDNA) analysis is a promising environmental education tool because it enables easy and comprehensive biodiversity assessment through simple water sampling. Despite several citizen-based surveys using eDNA analysis, minimal attention has been paid to its educational effectiveness. C_LIO_LIIn this study, we examined the educational feasibility of eDNA analysis by conducting an environmental education program that incorporated eDNA-based local fish surveys in three high schools in Japan. Through detailed questionnaire surveys conducted before and after the program, we verified whether our program increased student interest in biodiversity and ecosystem services. C_LIO_LIIn the program, students proactively identified diverse fish species living in the survey area by simply collecting water. The questionnaire survey results showed that student knowledge of and interest in biodiversity and ecosystem services increased after the program. Students became aware of local fish diversity and expressed their motivation to engage in conservation activities. We confirmed the educational impact of the program not only at the end but also immediately following the water sampling experience. C_LIO_LISynthesis and applications. These results provide the first empirical evidence of the positive effects of eDNA analysis on student environmental awareness and engagement. Our program provides a feasible model for eDNA-based environmental education. Because eDNA analysis can be applied to diverse target taxa that are unique to a given area, similar environmental education programs can be conducted for various citizen groups worldwide. Our research also suggested that eDNA-based environmental education was effective for younger generations with varying levels of interest and experience in nature, showing significant potential for addressing the extinction of natural experiences and motivating citizens to participate in ecosystem conservation activities. C_LI

scientific communication and education↗

bioRxiv2022

Mesophyll specific expression of a bacterial mercury transporter-based vacuolar sequestration machinery sufficiently enhances mercury tolerance of Arabidopsis.

We aimed to efficiently enhance plant Hg(II) tolerance by the transgenic approach utilizing a bacterial mercury transporter MerC, an Arabidopsis mesophyll specific promoter pRBCS1A, and a vacuolar membrane targeting syntaxin AtVAM3/SYP22. We generated two independent homozygous Arabidopsis pRBCS1A-TCV lines expressing mT-Sapphire-MerC-AtVAM3 under the control of pRBCS1A. Quantitative RT-PCR showed that the transgene was expressed specifically in shoots of pRBCS1A-TCV lines. Confocal analyses further demonstrated the leaf mesophyll specific expression of mT-Sapphire-MerC-AtVAM3. Confocal observation of the protoplast derived from the F1 plants of the pRBCS1A-TCV line and the tonoplast marker line p35S-GFP-{delta}TIP showed the tonoplast colocalization of mT-Sapphire-MerC-AtVAM3 and GFP-{delta}TIP. These results clearly demonstrated that mT-Sapphire-MerC-AtVAM3 expression in Arabidopsis is spatially regulated as designed at the transcript and the membrane trafficking levels. We then examined the Hg(II) tolerance of the pRBCS1A-TCV lines as well as the p35S-driven MerC-AtVAM3 expressing line p35S-CV under the various Hg(II) stress conditions. Short-term (12 d) Hg(II) treatment indicated the enhanced Hg(II) tolerance of both pRBCS1A-TCV and p35S-CV lines. The longer (3 weeks) Hg(II) treatment highlighted the better shoot growth of the transgenic plants compared to the wild-type Col-0 and the pRBCS1A-TCV lines were more tolerant to Hg(II) stress than the p35S-CV line. These results suggest that mesophyll-specific expression of MerC-AtVAM3 is sufficient or even better to enhance the Arabidopsis Hg(II) tolerance. The Hg accumulation in roots and shoots did not differ between the wild-type Col-0 and the MerC-AtVAM3 expressing plants, suggesting that the boosted Hg(II) tolerance of the transgenic lines would be attributed to vacuolar Hg-sequestration by the tonoplast-localized MerC. Further perspectives of the MerC-based plant engineering are also discussed.

plant biology↗

bioRxiv2021

Development of affinity beads-based in vitro metal-ligand binding assay reveals dominant cadmium affinity of thiol-rich small peptides phytochelatins beyond glutathione

For a better understanding of metal-ligand interaction and its function in cells, we developed an easy, sensitive, and high-throughput method to quantify ligand-metal(loid) binding affinity under physiological conditions by combining ligand-attached affinity beads and inductively coupled plasma-optical emission spectrometry (ICP-OES). Glutathione (GSH) and two phytochelatins (PC2 and PC3, small peptides with different numbers of free thiols) were employed as model ligands and attached to hydrophilic beads. The principle of the assay resembles that of affinity purification of proteins in biochemistry: metals binding to the ligand on the beads and the rest in the buffer are separated by a spin-column and quantified by ICP-OES. The binding assay using the GSH-attached beads and various metal(loid)s suggested the different affinity of the metal-GSH interactions, in accordance with the order of the Irving-Williams series and the reported stability constants. The binding assay using PC2 or PC3-attached beads suggested positive binding between PCs and Ni(II), Cu(II), Zn(II), Cd(II), and As(III) in accordance with the number of thiols in PC2 and PC3. We then conducted the competition assay using Cd(II), Mn(II), Fe(II), Cu(II), and Zn(II) and the results suggested a better binding affinity of PC2 with Cd(II) than with the essential metals. Another competition assay using PC2 and GSH suggested a robust binding affinity between PCs and Cd(II) compared to GSH and Cd(II). These results suggested the dominance of PC-Cd complex formation in vitro, supporting the physiological importance of PCs for the detoxification of cadmium in vivo. We also discuss the potential application of the assay.

biochemistry↗