TcJAMYC: A transcription factor that controls paclitaxel biosynthetic gene expression

Following our initial work characterizing the patterns of gene expression following MJ elicitation of Taxus suspension cultures, we hypothesized that the coordinated expression of the known paclitaxel pathway genes suggested control by a single regulatory regime. In model plant systems, particular MYC transcription factors (called JAMYCs) have been shown to modulate jasmonate defense responses. We reasoned that Taxus might have an evolutionarily conserved JAMYC, and sought to clone it. Taxus is a gymnosperm species that is at least 150 million years distant from commonly used model angiosperm species like Arabidopsis and rice. Nevertheless, we were able to identify a Taxus gene (TcJAMYC) that regulates expession from promoters of four of the genes in the paclitaxel biosynthetic pathway.