SAG and infection: Similar to the SAG pool, an increase in the transcript amounts of AtPR1 and AtPR3 was detected in the Mock-infiltrated transgenic plants, while infection with Pst DC3000 caused only a slight further increase in mRNA levels of AtPR1 and AtPR3 and their absolute levels were significantly lower than in Pst DC3000-infected wild type plants (Fig 5B).