Omics-based Identification of a Transcription Factor Gene Regulating Glucosinolate Biosynthesis Genes

Abstract

We obtained time-series data of the transcriptome and metabolome of sulfur-starved Arabidopsis. By analyzing the data using batch-learning self-organizing mapping, we found that known glucosinolate (GSL) biosynthesis genes were coexpressed under sulfur deficiency. Based on the assumption that unknown genes coexpressed with known GSL biosynthesis genes are also involved in GSL biosynthesis, we found a candidate gene encoding a transcription factor regulating GSL biosynthesis genes. We also conducted coexpression analysis using publicly available 1388 microarray data of AtGenExpress, and found that this gene is coexpressed with the genes involved in Met-derived GSL (MET-GSL). To confirm the predicted function as a transcription factor regulating MET-GSL biosynthesis genes, we analyzed the transcriptome and GSL profile of a knockout mutant and overexpressing T87 cell culture lines of this gene. The results showed that this gene is actually a positive regulator specific to MET-GSL biosynthesis genes but lesser for Trp-derived GSL biosynthesis genes.