Fig. 7.

Cyclosporin A inhibits auxin-induced expression of Aux/IAA genes. Relative expression of IAA10, IAA11, and the SGN-U346908 control gene determined in stem sections taken from rootstocks of the following scion/rootstock combinations: dgt/dgt (A), VFN8/dgt (B), and VFN8/VFN8 (C). Transcription levels were measured following one of the indicated treatments: incubation in control solution (black bars), in a solution containing 0.1 mM IAA (light grey bars), or in a solution containing 0.1 mM IAA + 10 µM CysA (dark grey bars). Transcription levels were normalized using tubulin as an internal control. To verify that IAA or CysA does not have a general impact on gene expression SGN-U346908, which was characterized as stable housekeeping gene (Expósito-Rodríguez et al., 2008), was selected as an internal control. Data represent means (±SE) (n=5 independent experiments). A Student’s t-test indicated a significant (P<0.05) effect of the chemical treatment on the expression levels within each grafting combination. Identical letters indicate no significant differences between each graft at P<0.05 by Tukey’s HSD-test.