Over-expression of transcription associated factor genes co-expressed with genes of the mevalonate pathway, upstream of isoprenoid biosynthesis, in Arabidopsis cultured cells

From a list of 3087 Arabidopsis putative transcription associated factor (TAF) genes including those possibly involved in transcription processes via their protein interaction, five TAF genes were related to genes upstream of isopentenyl diphosphate biosynthesis, i.e., the mevalonate pathway, by analyzing their network relationships with gene-to-gene Pearson's correlation coefficients calculated from 1388 DNA microarray results. We up-regulated the five candidate genes under the control of a cauliflower mosaic virus 35S promoter in Arabidopsis suspension-cultured T87 cells, and evaluated gene expression in the transgenic cells by DNA microarray analysis. All five of the genes were substantially up-regulated in each transgenic cell line, whereas none of the enzyme genes for the mevalonate pathway exhibited ally considerable up-regulation. The inconsistency between the co-expression relationship and lack of consequent Up-regulation suggests that it is difficult to find genes controlling isoprenoid upstream metabolites through co-expression analysis. Nevertheless, the results of this study are a basis for further study of isoprenoid synthesis.