Fig. 6

Validation of the tissue specificity of five putative root-preferential promoters in transgenic maize plants. Promoters of five root-preferential genes (GRMZM2G308463, GRMZM2G125023, GRMZM2G036629, GRMZM2G088531 and GRMZM2G091534) were analyzed for tissue specificity in transgenic maize plants. Approximately 2.0 kb upstream of the start codon were cloned as putative promoters and named p8463, p5023, p1534, p8531 and p6629. Root tissues at four developmental stages and six non-root tissues of transgenic and wild-type (control) maize were subjected to GUS staining. For 6 DAS-root, VE-root, and V2-root, bar = 1 cm; for flare stage-LS, bar = 5 mm; for V2-root tip, bar = 0.5 mm; for V2-leaf, flare stage-crown root, flare stage-stem, flare stage-leaf, spikelet, silk, and husk, bar = 1 mm