CRISPR/Cas9-mediated targeted mutagenesis of GmSPL9 genes alters plant architecture in soybean

BMC Plant Biology

Lam-Son Phan Tran¹  Shuilian Chen²  Xiaojuan Zhang²  Dezhen Qiu²  Dong Cao²  Aili Bao²  Haifeng Chen²  Limiao Chen²  Songli Yuan²  Qingnan Hao²  Wei Guo²  Zhonglu Yang²  Zhihui Shan²  Xinan Zhou²  Chanjuan Zhang²  Xia Li³  Baohui Liu⁴  Fanjiang Kong⁴ 

[1] Institute of Research and Development, Duy Tan University;Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences;State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University;The Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences;

关键词: CRISPR/Cas9;    Plastochron length;    Plant architecture;    Soybean;    SPL;   

DOI  :  10.1186/s12870-019-1746-6

来源: DOAJ

【 摘 要 】

Abstract Background The plant architecture has significant effects on grain yield of various crops, including soybean (Glycine max), but the knowledge on optimization of plant architecture in order to increase yield potential is still limited. Recently, CRISPR/Cas9 system has revolutionized genome editing, and has been widely utilized to edit the genomes of a diverse range of crop plants. Results In the present study, we employed the CRISPR/Cas9 system to mutate four genes encoding SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors of the SPL9 family in soybean. These four GmSPL9 genes are negatively regulated by GmmiR156b, a target for the improvement of soybean plant architecture and yields. The soybean Williams 82 was transformed with the binary CRISPR/Cas9 plasmid, assembled with four sgRNA expression cassettes driven by the Arabidopsis thaliana U3 or U6 promoter, targeting different sites of these four SPL9 genes via Agrobacterium tumefaciens-mediated transformation. A 1-bp deletion was detected in one target site of the GmSPL9a and one target site of the GmSPL9b, respectively, by DNA sequencing analysis of two T0-generation plants. T2-generation spl9a and spl9b homozygous single mutants exhibited no obvious phenotype changes; but the T2 double homozygous mutant spl9a/spl9b possessed shorter plastochron length. In T4 generation, higher-order mutant plants carrying various combinations of mutations showed increased node number on the main stem and branch number, consequently increased total node number per plants at different levels. In addition, the expression levels of the examined GmSPL9 genes were higher in the spl9b-1 single mutant than wild-type plants, which might suggest a feedback regulation on the expression of the investigated GmSPL9 genes in soybean. Conclusions Our results showed that CRISPR/Cas9-mediated targeted mutagenesis of four GmSPL9 genes in different combinations altered plant architecture in soybean. The findings demonstrated that GmSPL9a, GmSPL9b, GmSPL9c and GmSPL9 function as redundant transcription factors in regulating plant architecture in soybean.

【 授权许可】

Unknown