Figure 3.

GAMyb RNAi Specifically Reduces the GA-Mediated Induction of α-Amylase.

(A) Schemes of gene constructs. The sequence of the effector construct is identical to that of a part of the endogenous GAMyb gene. Arrowheads indicate the orientation of every gene or gene fragment. Numbers below the effector construct represent the size (in bp) of every segment (not drawn to scale).

(B) The GA-inducible reporter construct Amy-GUS was cotransformed with the Ubi1-Empty vector (−) or the effector construct Ubi1-GAMyb(RNAi) at a 1:1 ratio. Embryoless half-seeds then were incubated for 24 h with (+) or without (−) 1 μM GA₃.

(C) An ABA-inducible construct, HvA1-GUS (left) or HvA22-GUS (right), was cotransformed with the Ubi1-Empty vector (−) or with Ubi1-GAMyb(RNAi) at a 1:1 ratio. Embryoless half-seeds then were incubated for 24 h with (+) or without (−) 20 μM ABA.

For (B) and (C), bars represent normalized GUS activities ± se (n = 4).