Figure 7.

OsBSK3 regulates the BR response in rice. A, The lamina joint angle of the second leaves from 2-week-old rice seedlings overexpressing OsBSK3-myc. The 33 and 38 are two independent transgenic lines. B, Overexpression of the kinase domain of OsBSK3 (N390) enhanced the bending of the lamina joint in the transgenic rice seedlings. The upper panel shows the lamina joints of the second leaves from 2-week-old seedlings overexpressing C-terminal myc tag-fused OsBSK3 (BSK3) or kinase domain of OsBSK3 (N390). The lower panel shows the expression levels of OsBSK3-myc and N390-myc in the rice seedlings shown above using anti-myc antibodies. C, Quantitative analysis of BR-stimulated leaf lamina joint bending in OsBSK3- and N390-overexpressing rice seedlings. A total of 10 μL of the indicated concentration of eBL was applied to the lamina joint region of 10-d-old light-grown rice seedlings. The leaf bending angle was measured 3 d after eBL application. D, Quantitative analysis of BR-inhibited root elongation in OsBSK3- and N390-overexpressing rice seedlings. Seedlings were grown in Hoagland medium with or without 1 μm eBL for 1 week. Relative growth was calculated by dividing the root length in eBL by the root length under control conditions. E, Quantitative real-time RT-PCR analysis of DWARF and D2 expression in 2-week-old rice seedlings overexpressing OsBSK3 or N390. F, Left: qRT-PCR analysis of the expression of OsBSKs in 2-week-old wild-type and OsBSK3 CS transgenic rice seedlings. Right: Phenotypes of the seedlings used in the RT-PCR analysis. G, Internode length of fully grown wild-type and CS plants. H, Quantitative real-time RT-PCR analysis of DWARF expression in 2-week-old CS seedlings. I, Seeds from N390-overexpressing and CS transgenic rice plants. J, Weights of the seeds shown in I. A one-way ANOVA was performed in all experiments. Statistically significant differences are indicated by different lowercase letters (P < 0.05).