OsWNK9 regulates cadmium concentration in brown rice by restraining cadmium transport from straw to brown rice

作者：Zhipeng Guo, Jingyi Guo, Haiying Yu, Huagang Huang, Daihua Ye, Tao Liu, Xizhou Zhang, Lu Zhang, Zicheng Zheng, Yongdong Wang, Tingxuan Li · 发表于：Ecotoxicology and Environmental Safety · 年份：2024 · DOI：10.1016/j.ecoenv.2024.116810 · 被引用次数：6 · 研究领域：Plant Stress Responses and Tolerance、GABA and Rice Research、Medicinal Plants and Neuroprotection

Selecting and breeding rice cultivars that enable strong cadmium (Cd) accumulation in rice straw but low accumulation in brown rice is a promising way to achieve Cd phytoremediation as well as to ensure the food safety of rice. Herein, we isolated a gene OsWNK9 from the quantitative trait locus associated with reducing Cd translocation from rice straw to brown rice and decreasing the Cd concentration in brown rice (BRCdC). Continuous strong expression of OsWNK9 was observed in nodes and internode and was induced after Cd supply. OsWNK9 was localized in the rice cell nucleus and participated in the regulation of Cd transport in yeast. Two independent oswnk9 rice mutants were generated via CRISPR/Cas9 gene-editing and showed significantly higher BRCdC than that of the wild type (WT). The BRCdC of knockout oswnk9 mutants was 0.227 mg kg −1 and 0.238 mg kg −1 , increased by 14 % and 19 % compared with that of the WT due to the lower Cd allocation in the basal stem, internode, and node III, which was unrelated to Cd uptake. Interestingly, OsWNK9 could promote iron (Fe) accumulation in rice under Cd-contaminated conditions, suggesting that OsWNK9 is an ideal gene for Cd phytoremediation and Fe biofortification in rice to support safe food production. • OsWNK9 was a protein kinase-coding gene for regulating Cd content in brown rice. • OsWNK9 was localized in cell nucleus of rice mesophyll protoplast. • OsWNK9 was highly expressed in the nodes and restrained Cd translocation. • OsWNK...