The VirB2 peptide, S111-T58, induced the expression of defense-related genes in wild-type plants but to a lesser extent in RTNLB4 O/E transgenic plants. Gene expression of FRK1 (A), CYP81F2 (B), At2g17740 (C), WRKY22 (D), WRKY29 (E), MPK3 (F), and MPK6 (G) in seedlings of wild-type and RTNLB4 O/E transgenic plants treated with 10 µM VirB2 peptide for 0, 10, 30, 60, 90, 120, and 360 min measured by qPCR analysis. The UBQ10 (polyubiquitin 10) transcript level was an internal control. Data are mean ± SE from at least three independent biological experiments. Data were analyzed by Duncan tests and means with different letters were significantly different (p < 0.05).