The C Ppc promoters of many C grass species share a common regulatory mechanism for gene expression in the mesophyll cell.

C photosynthetic plants have evolved from C ancestors and are characterized by differential expression of several hundred genes. Strict compartmentalization of key C enzymes either to mesophyll (M) or bundle sheath cells is considered a crucial step towards the evolution of C photosynthesis. In this study, we demonstrate that the 5'-flanking sequences of the C type phosphoenolpyruvate carboxylase (Ppc) gene from three C grass species could drive M-cell-specific expression of a reporter gene in rice.