FBN6 and PSY can be immunoprecipitated together. N. benthamiana leaves were co-agroinfiltrated with the indicated combinations of proteins with C-terminal myc or GFP tags. Four days later, agroinfiltrated leaves were collected and used for protein extraction and analysis. Part of the protein extracts was used to test protein production (input) by immunoblot analyses with antibodies against myc (αmyc) or GFP (αGFP; asterisk marks the position of unspecific bands). The remaining protein extracts were used for co-immunoprecipitation (Co-IP) experiments using αmyc followed by immunoblot analyses with immunoblot analyses with αmyc (to confirm successful IP) and αGFP (to detect the presence of co-immunoprecipitated PSY-GFP protein). A) Experiment using the Calvin cycle enzyme PRK fused to the myc tag as a negative control. B) Experiment using the PG-associated FBN4 protein fused to the myc tag to test for the specificity of the FBN6-PSY interaction.