Fig. 1.

C₄ promoter-induced expression of NAC052 increases signal intensity of reporter gene expression in the leaf bundle and changes leaf morphology of C₃Arabidopsis thaliana. (A) Leaf morphology of 28-day-old A. thaliana reference line (Col-0 transformed with GFP under control of the Flaveria trinervia-derived GLDPA promoter) and the mutant line (reference line transformed with activation tagging construct with the F. trinervia-derived GLDT promoter). (B) GFP signal overview of first leaf of 14-day-old reference line and mutant line. (C) Quantification of GFP signal of first leaf of 14-day-old reference line and mutant line, n=5. (D) Overview of the genomic landing point of the F. trinervia-derived GLDT promoter in the activation-tagged line. An alternative start codon in-frame with the other two ATGs was discovered 32 bp downstream of the genomic landing point of the GLDT promoter. The grey dotted line represents disfunction of the endogenous NAC052 promoter in the activation-tagged line. (E) Presence/absence (RT–PCR) of the wild-type transcript nr2 and of the alternative 5'truncated transcript. (F) Quantification (qRT–PCR) of the NAC052 transcripts in the reference and mutant line.