Figure 5.

Sequence-replacement assay to determine the cis-elements for CO₂/light response in the core-regulatory region of Pptca2. CCRE1 and CCRE2 sequences and adjacent sequences within the core-regulatory region of Pptca2 were replaced by NotI restriction site (left half), and the GUS reporter assay was done with each transformant (right half). Cells were grown in 5% CO₂ or air in the absence or presence of light. Vertical bar indicates the dataset for each construct. Two independent clones of transformants carrying each manipulated promoter-reporter construct were selected for a set of reporter assays. Value is mean ± sd of three replicates. Statistical significance was determined by t test (*, P < 0.05; **, P < 0.01; ***, P < 0.001).