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More efficient photosynthesis has allowed C-4 plants to adapt to more diverse ecosystems (such as hot and arid conditions) than C-3 plants. To better understand C-4 photosynthesis, we investigated the expression patterns of C-4 genes (C4PPDK and PCK1) and their non-C-4 homologous genes (CyPPDK1, CyPPDK2, and PCK2) in the different organs of maize (Zea mays). Both C-4 genes and non-C-4 genes showed organ-dependent expression patterns. The mRNA levels of C-4 genes were more abundant in leaf organ than in seeds at 25 days after pollination (DAP), while non-C-4 genes were mainly expressed in developing seeds. Further, acetylation of histone H3 lysine 9 (H3K9ac) positively correlates with mRNA levels of C-4 genes (C4PPDK and PCK1) in roots, stems, leaves, and seeds at 25 DAP, acetylation of histone H4 lysine 5 (H4K5ac) in the promoter regions of both C-4 (C4PPDK and PCK1) and non-C-4 genes (CyPPDK1, CyPPDK2, and PCK2) correlated well with their transcripts abundance in stems. In photosynthetic organs (stems and leaves), dimethylation of histone H3 lysine 9 (H3K9me2) negatively correlated with mRNA levels of both C-4 and non-C-4 genes. Taken together, our data suggest that histone modification was involved in the transcription regulation of both C-4 genes and non-C-4 genes, which might provide a clue of the functional evolution of C-4 genes.