Figure 1. Transformation assays on RAR1 gene silenced plants of N. benthamiana and induction of RAR1 in response to Agrobacterium infection. (A) Transient transformation assay. Leaf disks of the gene silenced plants and control plants were inoculated with non-tumorigenic strain A. tumefaciens GV2260 carrying pBISN1 (At804; has the uidA-intron gene within the T-DNA). Leaf disks were collected periodically and were used for measuring the fluorescence of 4-methylumbelliferone (4-MU). (B) Leaf disk stable transformation assay. Leaf disks of silenced and control plants were inoculated with a non-tumorigenic strain, A. tumefaciens GV2260, harboring the binary vector pCAS1 (contains a bar gene within the T-DNA) and were incubated on callus inducing medium (CIM) with glufosinate ammonium (GF). Data represent the mean of 3 experiments with a minimum of 150 leaf disks each per treatment with their SE values shown as error bars. (C) Differential gene expression of RAR1 upon Agrobacterium infection. Individual leaves of a minimum of 3 N. benthamiana plants were syringe (needleless) infiltrated with either: buffer (10 mM MES, dotted bars); an avirulent strain A. tumefaciens A136 (lacks Ti plasmid – cannot transfer T-DNA, line bars); or a T-DNA transfer-competent strain, A. tumefaciens At804 (checkered bars). Asterisks denote significant difference compared with controls using Fisher's least significant difference test at P = 0.05.