Fig. 1. EAR motif is essential for BZR1 function in BR responses.

(a) Glutamine (Q) at position 285 in BZR1 is converted to stop codon in the bzs285 mutant. BIN2-DM: BIN2 docking motif. EAR: EAR motif.

(b) Intragenic mutant (bzs285) suppresses the constitutive activation of BR response of bzr1-1D. Seedlings were grown in the dark on the medium containing 2 µM propiconazole (PPZ). Scale bar: 5 mm.

(c) Both BZR1ΔEAR-OXs and bzr1-1DΔEAR-OXs show severe dwarfism. Plants were grown in the long-day condition (16 hr of light and 8 hr of dark) for 4 weeks. Two independent lines (1 and 2) for the BZR1ΔEAR-OXs and bzr1-1DΔEAR-OXs are shown.

(d) The hypocotyl elongation of bzr1-1DΔEAR-OX is inhibited by PPZ treatment. Seedlings were grown in the dark for 5 days on the medium containing either the mock or 2 µM PPZ. Error bars indicate the s.d. (n=10 plants). Scale bar: 5 mm.

(e) Axillary branches and cauline leaves are not fused in bzr1-1DΔEAR-OX.

(f,g) bzr1-1DΔEAR-OXs are insensitive to BR in the promotion of hypocotyl elongation (f) and the inhibition of primary root growth (g). Seedlings were grown under the white light for 5 days on the medium containing either mock or 1000 nM brassinolide (BL). Scale bar: 5 mm.

(h) BZR1ΔEAR-OXs are insensitive to BR in the promotion of hypocotyl elongation. Seedlings were grown under the white light for 5 days on the medium containing either mock or 1000 nM brassinolide (BL).

Error bars in (f–h) indicate the s.d. (n=10 plants).