Quantitative RT-PCR analysis of ABA biosynthesis genes in sis7 and wild-type germinating seeds. Relative expression levels were measured by qRT-PCR in Col, sis7-1 and sis7-3 germinating seeds treated with 300 mM Glc or 300 mM sorbitol. Data were obtained from two biologically independent experiments and relative mRNA levels were determined by using UBQ6 as a reference. The relative mRNA level of each gene in sorbitol-treated Col was set to 100. Bars indicate standard deviations.