Gene Expression Data Displaying Up-Regulation and Down-Regulation of Amino Acid Nutritional Metabolic Modules

Raw gene expression data and amino acid metabolic pathway of Saccharomyces cerevisiae were excavated by SMD (Stanford Microarray Database) and KEGG (Kyoto Encyclopedia of Genes and Genomes), respectively. The methionine and cysteine nutritional metabolic modules were selected and analyzed, expecting to establish the relationship between the modules, and find out the important genes, which made predominant contribution for the up-regulation and down-regulation of modules, to identify the differences and synergies in expression levels. The results show that four common genes exist between these two modules, comprising YAL012W (4.4.1.1), YFR055W (4.4.1.8), YJR130C (2.5.1.48) and YLR303W (2.5.1.49). For methionine modules, the five important genes were YAL012W (4.4.1.1), YDR502C (2.5.1.6), YER043C (3.3.1.1), YGR155W (4.2.1.22) and YLR303W (2.5.1.49), playing a decisive role in the gross of gene expression, while for cysteine modules, those are YAL012W (4.4.1.1), YLR303W (2.5.1.49), YNL247W (6.1.1.16) and YCL064C (4.3.1.17). Maybe the cooperative up-regulation relations exist between these two modules, while because of different gene numbers in modules, the synergies between gene expression gross values were not distinct. But certain crucial metabolite can be accumulated by controlling the important genes in the metabolic process.