Zhang Jiaojiao, Zhang Xiaofeng, Chen Rongrong, Yang Li, Fan Kaijian, Liu Yan, Wang Guoying, Ren Zhenjing, Liu Yunjun
Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
Front Plant Sci. 2020 Jul 9;11:1048. doi: 10.3389/fpls.2020.01048. eCollection 2020.
The "green revolution" gene gibberellin oxidase contributes to the semidwarf phenotype, improving product and lodging resistance. Dissecting the function of GA biosynthetic genes would be helpful for dwarf maize breeding. In this study, we edited the maize gene and generated semidwarf maize plants using CRISPR/Cas9 technology. Application of exogenous gibberellin can recover the dwarf phenotype, indicating that the mutants are gibberellin deficient. The contents of GA and GA were elevated in the mutants due to the disruption of GA20 oxidase, whereas the contents of other GA precursors (GA, GA, GA, GA, and GA) were decreased in the mutants, and the accumulation of bioactive GA and GA was also decreased, contributing to the semidwarf phenotype. Transgene-free dwarf maize was selected from T-generation plants and might be useful for maize breeding in the future.
“绿色革命”基因赤霉素氧化酶促成了半矮化表型，提高了产量和抗倒伏性。剖析赤霉素生物合成基因的功能将有助于矮化玉米育种。在本研究中，我们利用CRISPR/Cas9技术对玉米基因进行编辑，培育出了半矮化玉米植株。施加外源赤霉素可恢复矮化表型，表明这些突变体赤霉素缺乏。由于GA20氧化酶的破坏，突变体中GA1和GA4的含量升高，而其他赤霉素前体（GA12、GA53、GA19、GA20和GA29）的含量在突变体中降低，生物活性GA1和GA4的积累也减少，导致了半矮化表型。从T代植株中筛选出了无转基因的矮化玉米，这可能对未来的玉米育种有用。
