Abstract: In order to study the role of rice auxin response factor OsARF12 in the growth and development of rice, two different exon mutation targets of OsARF12 were designed by CRISPR/Cas9 gene editing technology, respectively. The specific sequences including mutation targets were synthesized and linked with intermediate vector sgRNA, and then recombined with the final vector Cas9 to obtain two independent expression vectors with different mutation targets. The single clone which was sequenced successfully was introduced into japonica rice variety Nipponbare by Agrobacterium tumefaciens mediated method to obtain transgenic plants, and the mutation types of mutant plants were analyzed by sequencing results. There were three homozygous mutations and two biallelic mutations in T₁ mutant KO-ARF12-1, with a total of five mutation types; There were 6 homozygous mutations, 4 biallelic mutations and 1 heterozygous mutation in KO-ARF12-2. The mutant lines with deletion of 1 nt, deletion of 4 nt, deletion of 7 nt and deletion of 2 nt, insertion of 1 nt, deletion of 5 nt were selected as the research objects. The results of fluorescence quantitative PCR showed that the expression of OsARF12 in the mutants was significantly lower than that in the wild type. Compared with the wild type, the plant height of the two mutants with different mutation types decreased significantly, with a decrease range of 13.15%-18.39%; There was no significant difference in the length of the first and second internodes, but the length of the third and fourth internodes decreased significantly by 21.91% and 23.46%. The OsARF 12 mutant created by CRISPR/Cas9 can regulate the internode extension and plant height, which is of great significance to improve the molecular regulation mechanism of auxin response factor in rice.

Key words: Rice, OsARF12, CRISPR/Cas9, Gene editing, Plant height

CLC Number: 

• S511.03

• Q78