Figure 5.

AtGH3.15 knockout and overexpression results in hypersensitivity and resistance to IBA in root elongation and lateral root density assays. A, seedlings of wildtype Col-0 (Col), SALK knockout lines (S108265 and S079153), and the 35S:FLAG-AtGH3.15 overexpression lines (1-5, 2-7, and 8-2) were grown under continuous yellow-filtered light for 18 days at 22 °C on medium supplemented with ethanol (mock) or 8 μm IBA. B, comparison of percentage root length change in 8 μm IBA-treated seedlings versus mock-treated seedlings grown for 18 days at 22 °C (see A). Percentage length of treated versus mock-treated was calculated as follows: (average root length IBA-treated seedling)/(average root length mock-treated seedling) × 100. C, effect of IBA treatment on lateral root density. Seedlings were grown under continuous yellow-filtered light for 10 days at 22 °C on medium supplemented with ethanol (mock) or 10 μm IBA. Lateral root density was calculated as number of lateral roots per mm root length. For B and C, error bars represent mean ± S.E. (error bars) (n = 20). *, p < 0.05; **, p < 0.001; and ***, p < 0.0001 versus wildtype.