Figure 9.

Expression of SnRK1-related genes in tomato seedling leaves in response to water stress or ABA. A, Leaves were sampled from well-watered plants and frozen immediately (lane 1) or were excised and placed in plastic bags containing moist filter paper either immediately (lane 2) or after different durations of initial water loss resulting in 90% (lane 3) or 80% (lane 4) relative water content (RWC). RNA was extracted from the leaves 6 h after excision. Excised shoots were placed with their cut ends in water (lane 5) or in 100 μm ABA (lane 6) for 6 h before the leaves were sampled for RNA. Intact seedlings (lane 7 = initial leaf samples) were sprayed once with 100 μm ABA and leaves were sampled at 6 (lane 8), 12 (lane 9), and 24 h (lane 10) after treatment. rRNA, Ethidium bromide-stained gel showing loading of RNA in each lane. Replicate gels were run with identical samples and hybridized with RNA probes for LeSNF4, LeSNF1, or StubGAL83 (to detect LeGAL83 mRNA). B, Relative mRNA abundance was quantified by densitometry from the images in A and normalized for RNA loading in each lane. Within each panel, the normalized signal intensity of control leaves (lane 1) was set equal to 1, and the normalized signal intensities in other lanes are shown relative to it.