Transcriptome profiling of the basal region of poplar stems during the early gravitropic response

Young poplar stems show a preponderantly primary growth in the top internodes and differential cambium activity in the basal internodes after inclination with some tension wood formed after 45 min. This study was conducted in order to characterize the early changes in gene expression during early stages of the gravitropic response in the poplar. Hybridizations were performed to compare gravistimulated poplar stems (basal region) after 45 min of inclination and untreated control stems. Two biological replicates were done. Two hybridizations with a dye swap for each tree pair were done, making a total of four hybridizations.