FIGURE 8.

Quantification of GintAMT3 under phosphate stress. Gene expression was measured by quantitative polymerase chain reaction in the ERM and IRM of (A) inoculated P. trichocarpa and S. bicolor and in (B) microdissected arbusculated cells in S. bicolor. (A) The sorghum and poplar plants grew in a tripartite compartment system where only the fungus had access to the high phosphorous source (open bars) or low phosphorous source (closed bars). Differences between ERM and IRM were tested with a one-way ANOVA. Data were calibrated by the expression values obtained for the gene encoding the transcription elongation factor TEF1α. Values are means of nine replicates, error bars represent SD. Difference between treatments were tested with a one-way ANOVA. Lower case letters indicate significant difference (Tukey’s t-test; p < 0.05). (B) Inoculated S. bicolor grew in a two-partite compartment system where only the fungus had access to the high phosphorous (open bars) or low phosphorous (closed bars) source. Arbusculated cells were laser microdissected and transcript abundances of GintAMT3 and GintMST2 (monosaccharide transporter essential for functional symbiosis, Helber et al. (2011)) as a positive control were measured by qPCR. Data were calibrated by the expression values obtained for the gene encoding the transcription elongation factor TEF1α. Values are means of six replicates, error bars represent SD. Difference between treatments was tested with Tukey’s t-test (p < 0.05).