Fig. 3

Different patterns of expression obtained through real-time PCR for the StAPI5 gene and the virus coat protein gene of potato virus Y (PVY) and potato virus A (PVA) in the transgenic and non-transgenic potato plants. a Relative gene expression of StAPI5 at the same developmental stages and tissues. Blue braces, basal levels of the endogenous transgene StAPI5; green braces, induction of the endogenous transgene StAPI5 under virus stress conditions, and gray brace, the expression of exogenous StAPI5 under the control of the CaMV 35S promoter in the transgenic plants. b Expression of coat protein gene (PVY and PVA) in StAPI5-OE transgenic potato plants compared to the healthy control ones. WT: wild-type, Resistant: resistant, and StAPI5-OE: transgenic potato plants. In each case, Mock: mock-inoculated plants, PVY: plants infected with PVY, and PVA: plants infected with PVA. As a positive control of the experiment, the susceptible cv. Desiree to PVY and PVA and as negative controls, Mock-inoculated plants and resistant cv. Degima were used. All the treatments were performed in three biological and technical replicates, respectively. The averages of the fold changes were plotted (± SE) for the three events in each treatment group. Data were calculated based on the 2^–ΔΔCt method using the 18S rRNA gene as an internal control. Columns sharing same letter are not statistically different at the P < 0.05 according to the Duncan’s Multiple Range test. c Promoter sequences comparison of the endogenous StAPI5 and CaMV 35S to predict the potential transcription factor binding sites using the CiiiDER tool. The transcription factor binding sites are represented by colored boxes and introduced with the same color on the right. The boxes that are above and below the line represent the sites on positive and negative strands, respectively