Figure 5.

BES1 Expression in Protoplast.

(A) and (B) Confocal images of cowpea protoplasts transiently expressing BES1-GFP (A) and bes1-GFP ([B], green) 3 h after transfection. The nuclear-localized fluorescent protein is indicated by arrowheads.

(C) to (E) Confocal images of Arabidopsis protoplasts derived from different BR biosynthetic mutants, cbb1 (C), det2-1 (D), and dwf4 (E), and transiently expressing BES1-GFP. In all images, the chlorophyll autofluorescence is shown in red.

(F) Immunoblot analysis of the transiently expressed BES1-GFP protein in Arabidopsis protoplasts detected with anti-BES1 antibody. The blot shows that fast migrating band of ∼65 kD representing the unphosphorylated BES1-GFP is present in Arabidopsis protoplasts without and after BL treatment (lanes 1 and 2, respectively). Lane 3 contains protein extract from protoplasts cotransfected with BRI1-CFP and AtSERK3-YFP. An asterisk indicates additional bands that correspond in size to the endogenous BES1 proteins.