A transposon insertion in the 5′ UTR of OsPT1 reprograms its expression pattern and promotes cadmium accumulation in rice grains. Peng, SS; Wang, D; Liu, JL; Jiang, S; Xu, YC; Deng, YF; Zhou, XL; Hu, FZ; Liu, Z; Peng, Y; Ao, HJ; Xiao, YH; Wang, JR ; Zhao, JL; Liu, B; Yi, KK; Bai, LY; Wang, GL; Kang, HX
Source Plant Communications
Published JAN 12 2026
DOI: 10.1016/j.xplc.2025.101566
IF 11.6
Abstract Cadmium(Cd)accumulationinricegrainspresents a serious risk to human health; however, the mechanisms underlying this process remain incompletely understood. In this study, a genome-wide association analysis identified 29 loci associated with grain Cd content (LAGCCs). Among these, one of the most strongly associated loci, LAGCC4, contains the transporter geneOsPT1, whose haplotypes show a strong correlation with Cd content inricegrains. Atransposon, H-MITE, inserts into the5' untranslated region (UTR) ofOsPT1, altering itsexpressionpatternand leading to increased Cdaccumulation. Furthermore, we identified the transcription factor OsbHLH35, which specifically binds to the OsPT1H-MITE promoter to regulate its transcription in response to Cd stress. Targeted knockout of either OsPT1H-MITE or OsbHLH35 via CRISPR-Cas9 gene editing significantly reduced grain Cd content, with reductions ranging from 61.7% to 80.6%. This study reveals a previously unrecognized mechanism contributing to high Cdaccumulationinriceand identifies genetic targets for breedingricevarieties with reduced Cd content.