Figure 5.
Expression of tomato Chi9 and GluB mRNAs in response to different phytohormones or to wounding in imbibed wild-type cv MM or gib-1 tomato seeds or cv MM leaves. Seeds were imbibed for 48 h in water, 1 mm SA, 100 μm MeJA, 100 μm ABA, or 100 μm GA4+7 (GA) at 25°C before total RNA extraction. For ethylene (C2H4) treatment, gib-1 seeds were imbibed in water and were exposed to 10 μL L-1 ethylene for 48 h in a sealed glass chamber at 25°C. Twelve hours after spraying with phytohormone or wounding (W), tomato leaves were harvested from the first and second (above the cotyledon) fully expanded leaves of 3- to 4-week-old cv MM seedlings for total RNA isolation. Ethephon (ETH) aqueous solution (5 mm) was sprayed on the leaves for ethylene treatment. Total RNA (10 μg) was loaded in each well for RNA gel-blot analysis. Chi9 and GluB transcripts were quantified by a Storm PhosphorImager (Molecular Dynamics) and were normalized by the rRNA in each lane. The numbers below each lane in the top two panels give expression levels relative to water-imbibed cv MM seeds (lane 1 = 1 unit). Lane numbers are indicated below the bottom panel.