Transcript co-regulation for identifying genes involved in glucosinolates metabolism and regulation in Arabidopsis

Glucosinolates (GS) are a small group of group of secondary metabolites derived from aminoacids and containing N and S. We use transcript co-regulation (from public microarray data) to identify genes involved in the pathway or its regulation. Several genes are co-regulating with the enzymes involved in the three major GS pathways from Arabidopsis (Trp, Phe and Homomet). We can suggest candidates for: i. unidentified enzymatic steps, ii. transporters involved in GS movement, iii. pathway regulators. Candidate genes identified are: A) Several Glutathione S-transferases as donor for the reduced sulfur. B) Two aminotransferases acting on methionine as a first step either prior to or after side chain elongation. C) Three aconitases-like proteins (At3g58990, At4g13430 and At2g43100) involved in the hydroxyl migration during chain elongation in homomethione derived GS. D) PEN3 (At1g59870) as the ABC transporter of Trp-derived GS across the plasma membrane and PEN2 (At2g44490) as the glycosyl hydrolase family 1 protein involved in their transport and hydrolysis at infection sites. E) A transporter acting on methionine-derived GS. F) Several MYB genes as regulators.