Expression of TTG1 under the control of its native promoter restores trichome formation in the ttg1Δ15aa mutant. (a) Trichome formation on leaves of 10-day-old seedlings (up panel), 4-week-old plants (middle panel), and stems of 5-week-old plants (lower panel) of the Col wild type, the ttg1Δ15aa mutant, and the TTG1/ttg1Δ15aa transgenic plants. Seeds of Col wild type, the ttg1Δ15aa mutant, and the TTG1/ttg1Δ15aa transgenic plants were germinated and grown in soil pots. Pictures were taken directly or under a Motic K microscope by using an EOS 1100D digital camera at indicated stages. (b) Trichome numbers on the first two, third, fourth, fifth and sixth rosette leaves of the Col wild type, the ttg1Δ15aa mutant, and the TTG1/ttg1Δ15aa transgenic plants. Trichome numbers on the indicated leaves were count under a Motic K microscope. Date represence mean ± SD of 10–14 leaves. *, Significantly different from that in the Col wild type (student’s t test, p < 0.0001).