Plasmid construction and genetic transformation
The ORF of SmGRAS5 was amplified and cloned into the Noc I and Spe I restriction sites of the pCAMBIA1304 in sense and antisense orientations with the CaMV35S promoter. PCR and restriction enzyme digestion were used to confirm the positive clones. And then the plasmids were transformed into ATCC15834 . The combination of cefotaxime (Sigma, USA) and hygromycin B (MP Bio, USA) was used to screen the transformants. PCR identification and the positive transgenic lines screening use four primer pairs, rolB , rolC , hptII , 35S forward primer (35S-F) and GRAS5 reverse primer (GRAS5-R). All the expression vector construction and the PCR identification primers are listed in Supplementary Table S2.