C4 gene expression

C-4 plants, including maize, Flaveria, amaranth, sorghum, and an amphibious sedge Eleocharis vivipara, have been employed to elucidate the molecular mechanisms and signaling pathways that control C-4 photosynthesis gene expression. Current evidence suggests that pre-existing genes were recruited for the Cs pathway after acquiring potent and surprisingly diverse regulatory elements. This review emphasizes recent advances in our understanding of the creation of C-4 genes, the activities of the C-4 gene promoters consisting of synergistic and combinatorial enhancers and silencers, the use of 5' and 3' untranslated regions for transcriptional and posttranscriptional regulations, and the function of novel transcription factors. The research has also revealed new insights into unique or universal mechanisms underlying cell-type specificity, coordinate nuclear-chloroplast actions, hormonal, metabolic, stress and light responses, and the control of enzymatic activities by phosphorylation and reductive processes.