Function of in the Release of Acetophenones in White Spruce

Eastern spruce budworm ( Clemens) (ESBW) is a major forest pest which feeds on young shoots of white spruce () and can cause landscape level economic and ecological losses. Release of acetophenone metabolites, piceol and pungenol, from their corresponding glycosides, picein and pungenin, can confer natural resistance of spruce to ESBW. A beta-glucosidase gene, , was recently discovered and the encoded enzyme was characterized to function in the release of the defensive acetophenone aglycons. Here we describe overexpression of in a white spruce genotype whose metabolome contains the glucosylated acetophenones, but no detectable amounts of the aglycons. Transgenic overexpression of resulted in release of the acetophenone aglycons . This work provides evidence for the function of .