Figure 2From: Comprehensive analysis of tobacco pollen transcriptome unveils common pathways in polar cell expansion and underlying heterochronic shift during spermatogenesisQuantitative RT-PCR validation of microarray gene expression. Relative expression levels of selected genes determined at mature pollen (MP) and at four stages of pollen-tube growth (4, 13, 24 and 48 h of cultivation). On the secondary axis, corresponding normalized expression signal at two pollen stages (MP and PT4) derived from microarray chip hybridization. The tobacco 18S RNA gene was used to normalize obtained Ct values to compute relative expression levels at each stage of the pollen gametophyte development.Back to article page