Expression data from PSARK::IPT Nicotiana and wildtype plants

Stress-induced leaf senescence could be delayed in transgenic plants expressing isopentenyltransferase (IPT), an enzyme that catalyzes the rate-limiting step in CK synthesis under the control of SARK, a maturation- and stress-inducible promoter (Rivero et al., 2007). Increased CK production resulted in enhanced drought tolerance of the transgenic PSARK::IPT plants, with minimal yield loss (Rivero et al., 2007). We have used a large-scale expression profiling approach to investigate the effects of PSARK::IPT on gene expression to elucidate the molecular events associated with the CK-induced drought tolerance displayed by the PSARK::IPT plants. We used tomato genechips to capture the differential transcriptional responses of WT and PSARK::IPT plants under control and water stress conditions Leaf samples from well watered (1000 mL per day) and water stressed (300 mL per day) plants were collected for RNA extraction and hybridization on Affymetrix microarrays after 45 days of stress.