Figure 1.

D6PK Is Required for Phototropic Growth Responses.

(A) Representative photographs of 5-d-old wild-type and mutant seedlings after exposure for 20 h to unilateral white light (100 µmol m⁻² s⁻¹). Please note that variations in the position of the bending zone on the hypocotyl do not reflect variations in the phenotype but are the result of the respective position of the seedling on the plate and its distance to the light source. Col, Columbia. Bar = 10 mm.

(B) and (C) Quantification of hypocotyl bending in 5-d-old etiolated seedlings exposed for 20 h to unilateral white light (WL; 100 µmol m⁻² s⁻¹) (B) or unilateral blue light (BL; 120 µmol m⁻² s⁻¹) (C). The graphs show the average and sd of three representative experiments with at least 12 seedlings. Agravitropically growing seedlings were reoriented toward the gravity vector in safe green light before phototropism response experiments were initiated.

(D) Average and sd of the leaf flattening index determined from leaf number 5 from 25-d-old plants. The leaf flattening index is the ratio of the maximum width before and after manual flattening of the leaf.

(E) Representative photographs of cross-sectioned leaves of the wild type and d6pk012 mutants. Student’s t test, compared with Col: *0.01 < P < 0.05; **0.001 < P < 0.01; ***P < 0.001. Bar = 1 mm.