Fig. 3.

Transcription factors known to be involved in stomatal and non-stomatal limitations to CO₂ photosynthetic assimilation. Line arrows represent a positive effect while lines ending with a bar indicate a negative effect. Block arrows show the direction of the stomatal movement mediated by the transcription factor. Dashed lines represent possible interactions. Additional transcription factors as well as the existence of other links cannot be ruled out. Transcription factors are in red. ABA, abscisic acid; PSI, photosystem I; PSII, photosystem II; ABI3, ABA-insensitive 3; SNAC1, stress-responsive NAC 1; SPCH, Speechless; FLP, Four Lips; ICE1, Inducer of CBF Expression 1; SCRM2, SCREAM2; MYB, myeloblastosis oncogene; Ppcl, CAM-specific isozyme of phosphoenolpyruvate carboxylase; GapI, NAD-dependent glyceraldehyde-3-phosphate dehydrogenase.