OsABCG2 Controls Cadmium Accumulation in Rice Grains

doi:10.1016/j.rsci.2025.06.008

Abstract

Yu Haipeng, Zhong Kaizhen, Zhang Zhen, Chen Mingxue, Zhang Weixing, Li Huijuan, Huang Guanrong, Huang Zengying, Tang Lu, Yang Pengfei, Zhong Zhengzheng, Hu Guocheng, Yu Guoping, Wu Dezhi, Tong Hanhua, Zhang Peng. OsABCG2 Controls Cadmium Accumulation in Rice Grains[J]. Rice Science, 2025, 32(6): 766-771.

Figures/Tables 1

Fig. 1. Genome-wide association analysis of cadmium (Cd) accumulation in Ting’s core collection and functional analysis of OsABCG2. A and B, Manhattan plots for Cd accumulation in 2013 (A) and 2016 (B) using EMMAX. The blue and red fonts represent the cloned genes related to Cd and the novel QTL regions identified in the present study, respectively. Blue, red, and black horizontal dashed lines indicate the significant thresholds of 8.71 [-log10(1.94 × 10-9)], 7.71 [-log10(1.93 × 10-8)], and 5.09 [-log10(8.17 × 10-6)], respectively. C and D, Quantile-Quantile plots for Cd accumulation in 2013 (C) and 2016 (D). Red and blue symbols represent expected -log10(P-value) and observed -log10(P-value), respectively. E, Haplotype analysis of OsABCG2. Blue frame, white frame, and white triangle represent the exon, promoter, and 3′-untranslated region of OsABCG2, respectively. The numbers with minus and plus markers represent the positions to start codon of variations in promoter and coding sequence regions, respectively. F, Cd contents in grains of different haplotypes in Ting’s core collection. G and H, Relative expression of OsABCG2 in Nipponbare’s roots (G) and leaves (H) exposed to CdCl2 (20 μmol/L). I, β-Glucuronidase (GUS) staining in root, stem, leaf at the seedling stage, and grains driven by OsABCG2 promoter. J, Subcellular localization of OsABCG2. OsPM1-mCherry is the plasma membrane (PM)-localization marker. Scale bars, 10 µm. K, Performances of seedlings with (1 μmol/L) or without (CK) CdCl2 among wild type (WT, Nipponbare), OsABCG2 knockout lines (CRISPR-OsABCG2-1 and CRISPR-OsABCG2-2), and overexpression lines (OXOsABCG2-1 and OXOsABCG2-2). Scale bar, 4 cm. L and M, Root length (L) and plant height (M) of seedlings with (1 μmol/L) or without (CK) CdCl2 among WT, OsABCG2 knockout lines (CRISPR-OsABCG2-1 and CRISPR-OsABCG2-2), and overexpression lines (OXOsABCG2-1 and OXOsABCG2-2). Data are mean ± SD (n = 8-10). N, Comparison of Cd accumulation in grains among WT, OsABCG2 knockout lines (CRISPR-OsABCG2-1 and CRISPR-OsABCG2-2), and overexpression lines (OXOsABCG2-1 and OXOsABCG2-2). * and ** represent P < 0.05 and P < 0.01 levels by the Student’s t-test.

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