To elucidate whether the increase in PA14 pathogen resistance described above was due to Se(IV) regulating SKN-1-dependent gene expressions, the mRNA levels of glutathione-S-transferase (GST-4) and gamma-glutamine cysteine synthetase (GCS-1) in response to Se(IV) treatment and PA14 infection were examined. This evidence concerns the gene HPGDS and infection.