Induction of atTOC132 , atTOC120 and atTOC90 expression by endogenous intron. The GUS expression of cotyledons, root tips, leaves and mature flowers was demonstrated by histochemical staining. Cotyledon and root tip were collected from 5-day-old etiolated seedlings transferred to continuous light treatment for 4 hours. Rosette leaf was harvested from 2-week-old plate-grown plants. Mature flower was collected from soil-grown plants. These tissues were incubated in GUS buffer for 1.5 hours (cotyledon and root tip), 3 hours (leaf) and 24 hours (flower) at 37°C. The tissues were observed and photographed by confocal microscope with visible light source (Leica TCS SP2) and EOS 600D software (Canon) (cotyledon and root tip), digital camera (Ricoh CX3, rosette leaf), stereo microscope (Leica M3Z) and digital camera (Nikon Coolpix P5100) (flower). 132PUI, 132P, 120PUI, 120P, 90PUI and 90P plants shown here were their homogenous T3 transgenic lines, 132PUI-7, 132P-13, 120PUI-3, 120P-28, 90PUI-3 and 90P-9, respectively. Arrows indicate the anthers.