Characterization and Evaluation of OsLCT1 and OsNramp5 Mutants Generated Through CRISPR/Cas9-Mediated Mutagenesis for Breeding Low Cd Rice
Liu Songmei,
Jiang Jie,
Liu Yang,
Meng Jun,
Xu Shouling,
Tan Yuanyuan,
Li Youfa,
Shu Qingyao,
Huang Jianzhong
Affiliations
Liu Songmei
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China; Hubei Collaborative Innovation Center for Grain Industry, Jingzhou 434025, China
Jiang Jie
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China; Hubei Collaborative Innovation Center for Grain Industry, Jingzhou 434025, China
Liu Yang
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China; Hubei Collaborative Innovation Center for Grain Industry, Jingzhou 434025, China
Meng Jun
Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment/College of Environmental and Natural Resource Sciences, Zhejiang University, Hangzhou 310058, China
Xu Shouling
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China
Tan Yuanyuan
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China
Li Youfa
Jiaxing Academy of Agricultural Sciences, Jiaxing 314016, China
Shu Qingyao
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China; Hubei Collaborative Innovation Center for Grain Industry, Jingzhou 434025, China
Huang Jianzhong
National Key Laboratory of Rice Biology/Institute of Nuclear Agricultural Sciences, Zhejiang University, Hangzhou 310058, China; Corresponding author.
To explore how rice (Oryza sativa L.) can be safely produced in Cd-polluted soil, OsLCT1 and OsNramp5 mutant lines were generated by CRISPR/Cas9-mediated mutagenesis. One of OsLCT1 mutant (lct1×1) and two of OsNramp5 mutants (nramp5×7 and nramp5×9) were evaluated for grain Cd accumulation and agronomic performances. In paddy field soil containing approximately 0.9 mg/kg Cd, lct1×1 grains contained approximately 40% (0.17 mg/kg) of the Cd concentration of the wild type parental line, less than the China National Food Safety Standard (0.20 mg/kg). Both OsNramp5 mutants showed low grain Cd accumulation (< 0.06 mg/kg) in the paddy (approximately 0.9 mg/kg Cd) or in pots in soil spiked with 2 mg/kg Cd. However, only nramp5×7 showed normal growth and yield, whereas the growth of nramp5×9 was severely impaired. The study showed that lct1×1 could be used to produce rice grains safe for human consumption in lightly contaminated paddy soils and nramp5×7 used in soils contaminated by much higher levels of Cd. Keywords: cadmium, rice, OsNramp5, OsLCT1, genome-editing, heavy metal contamination, CRISPR, Cas9
