Figure 5.

SOBIR1 is required for RBPG1-dependent responsiveness. A, Response of Arabidopsis mutants to BcPG3. Leaves were photographed 7 d after infiltration with BcPG3 (1.5 µm). B, Coimmunoprecipitation (Co-IP) of RBPG1 and SOBIR1, SERK2, BAK1, or EFR and of BcPG3 and SOBIR1 is shown. Total proteins expressed in N. benthamiana leaves were subjected to immunoprecipitation (IP) with GFP Trap beads, followed by immunoblot analysis with anti-myc antibodies to detect RBPG1-myc and BcPG3-myc as well as with anti-GFP antibodies to detect SOBIR1-GFP, SERK2-GFP, BAK1-GFP, and EFR-GFP. The black arrow indicates the full-length SOBIR1-GFP protein, and the other bands are unspecific products. C, Lesion diameter caused by B. cinerea at 3 dpi on Arabidopsis leaves. Data represent means ± sd (n ≥ 15). D, Col-0 and sobir1-1 mutant plants were infiltrated with water or BcPG3 and 24 h later inoculated with Hpa isolate Noco2. Conidiophores were counted at 6 dpi. Results are averages ± se (n = 15). *P < 0.01 by Student’s t test. All experiments were repeated at least three times with similar results.