Deep Evolutionary Comparison of Gene Expression Identifies Parallel Recruitment of Trans-Factors in Two Independent Origins of C4 Photosynthesis
Venation, bundle sheath cell (BS) size, mesophyll (M) cell size and abundance of C4 transcripts and proteins in the base, middle and tip of 3 mm leaves as well as fully mature leaves of C. gynandra. (A) Leaves of 3 mm length possess a gradient in venation density from base to tip, whereas in mature leaves (B) this gradient is no longer visible, insets show representative images of samples used for RNA isolation. (C) Quantification of venation density and complexity. (D) Transverse sections and quantification of BS and M cell size. (E) Quantitative RT-PCR for the CA4, PPC2, NAD-ME2 and PPDK of genes important in the C4 cycle. (F) Abundance of carbonic anhydrase, phosphoenolpyruvate carboxylase, NAD-dependent malic enzyme and pyruvate,orthophosphate dikinase proteins from the base (B), middle (M), tip (T) and mature (Mat) leaves. Scale bars in A and B represent 0.3 mm and 3 mm respectively, while 1 mm gradations are shown within the insets.