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Journal of Integrative Agriculture  2026, Vol. 25 Issue (1): 390-393    DOI: 10.1016/j.jia.2025.08.011
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Overexpression of OsCAX2 in indica rice reduces cadmium accumulation in grains without yield loss

Zhi Hu1, Wenli Zou2, 3, 4, Huijing Ye1, Jie Ma1, Lijun Meng3, 5#, Jingguang Chen1#, Guoyou Ye2, 3, 6

1 School of Agriculture and Biotechnology, Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China

2 CAAS-IRRI Joint Laboratory for Genomics-Assisted Germplasm Enhancement/Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences (CAAS), Shenzhen 518120, China

3 Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture/Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs/Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China

4 School of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang 330038, China

5 Kunpeng Institute of Modern Agriculture at Foshan, Foshan 528225, China

6 Rice Breeding Innovations Platform, International Rice Research Institute (IRRI), Metro Manila 1301, Philippines

 Highlights 
OsCAX2 is localized to tonoplast, and cadmium induces its expression.
OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.
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摘要  

镉(Cd)作为类致癌物,米是亚洲人群Cd摄入的主要途径,尤其在中国南方稻田Cd污染高风险区。研究发现,水稻钙/氢离子交换蛋白基因OsCAX2在根中的表达受Cd胁迫诱导上调。亚细胞定位证实OsCAX2蛋白定位于液泡膜。水培实验表明,OsCAX2过表达株系根系Cd积累显著增加,而地上部Cd积累显著减少,根向地上部的Cd转运率降低43.7%,且植株生长未受影响;在Cd污染土壤(1 mg kg⁻¹ Cd)下种植发现,过表达株系糙米和剑叶中Cd含量分别较野生型显著降低49.1%39.7%关键农艺性状及产量无显著变化。这些结果表明,过表达OsCAX2可能通过增强根细胞液泡对Cd的区隔化存储,有效阻遏Cd向地上部及籽粒转运,为培育适用于中国南方Cd污染区的低Cd积累高产籼稻品种提供了重要的理论基础和基因资源。



Received: 20 June 2025   Accepted: 25 July 2025 Online: 05 August 2025  
Fund: 

This work was financially supported by the National Key R&D Program of China (2024YFD1200800) and the Guangdong Basic and Applied Basic Research Foundation, China (2024A1515030094).

About author:  #Correspondence Lijun Meng, E-mail: menglijun@caas.cn; Jingguang Chen, E-mail: chenjg28@mail.sysu.edu.cn

Cite this article: 

Zhi Hu, Wenli Zou, Huijing Ye, Jie Ma, Lijun Meng, Jingguang Chen, Guoyou Ye. 2026. Overexpression of OsCAX2 in indica rice reduces cadmium accumulation in grains without yield loss. Journal of Integrative Agriculture, 25(1): 390-393.

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