Figure 5.

Expression of NopM and C338A in L. japonicus roots. Agrobacterium rhizogenes-mediated transformation was used to obtain transgenic roots expressing NopM or the enzymatically inactive variant C338A. Plants transformed with the empty vector (ev) containing an RFP expression cassette were used as a negative control. A, proteins from transgenic roots were isolated 30 days after transformation, and 5 μl of extracts were used for Western blot (WB) analysis with anti-NopM and anti-RFP antibodies. B, examples of pink nodules formed on the transformed L. japonicus roots 25 days after inoculation with M. loti MAFF303099 (GFP). Transgenic roots show RFP expression (red fluorescence). Green fluorescence indicates the presence of bacteria within nodules. Bars, 500 μm. C, quantification of nodule biomass (dry weight (DW)) and number of formed nodules per plant. Data indicate mean ± S.E. (n = 10). NopM-expressing roots formed significantly fewer nodules (different letters indicate differences; Kruskal-Wallis test, p < 0.05).