Methyl jasmonate-induced enhancement of expression activity of Am-FaPS-1, a putative farnesyl diphosphate synthase gene from Aquilaria microcarpa

A cDNA clone, designated Am-FaPS-1 (1310 bp), was isolated from callus culture derived from the leaf tissues of Aquilaria microcarpa. This gene contains an open reading frame encoding the protein of 342 amino acid residues with high homology to farnesyl diphosphate synthase from various plant sources. An appreciable increase in the transcriptional level of Am-FaPS-1 was reproducibly observed by the exposure of the cell culture to methyl jasmonate. The expression activity of the gene was also elevated when the cells were treated with yeast extract and Ca²⁺-ionophore A23187. These results suggest that Am-FaPS-1 and its translate play roles in methyl jasmonate- and yeast extract-induced responses of A. microcarpa, and Ca²⁺ functions as an important messenger molecule in these processes. This set of the results would support our hypothesis that the activation of Ca²⁺-cascade evoked by the elevation of cytoplasmic Ca²⁺ concentration is an essential early event in methyl jasmonate-induced responses of higher plant cells.