Transcriptome-based network analysis of cell cycle-related genes in response to blue and red light in maize.

In maize, blue and red light are key environmental factors regulating cell-cycle progression. We used transcriptomics to investigate and compare differential gene expression under the four light conditions: red light, blue light, red converted to blue and blue converted to red. A total of 23 differentially expressed genes were identified. The gene-gene interaction analysis indicated a significant interaction between four unidentified genes, 100191551 , pco143873 , 100284747 and pco060490 , and cell-cycle-related genes. Using multiple sequence alignment analysis and protein structure comparisons, we show here that these four unidentified genes were characterized as ALP1-like , ALP1 , cyclin P1-1 and AEBP2 , respectively. By constructing a protein-protein interaction network, we inferred that 100191551 and pco143873 are potentially regulated to avoid DNA damage by abiotic stress response factors in the cell cycle. The gene 100284747 regulates the cell cycle in response to phosphate starvation signalling. The gene pco060490 potentially negatively regulates the cell cycle through the mediation of Histone H3 and CYCD6 in response to red light. In conclusion, the cell-cycle-related genes are sensitive to blue and red light, and four novel functional genes may be involved in the cell cycle.