Transcript abundance of genes involved in primary metabolism was also differentially affected; in fact, MJ enhanced expression of genes encoding the large RuBisCo subunit (RbcL) and PSII 32 kDa protein (PsbA). Another evident effect was the transcriptional repression of x-6 desaturase (x-6-DES) and stearoyl-ACP-desaturase (SSI2), both of which are involved in fatty acid desaturation, and of a pyruvate decarboxylase 1 (PDC1).