Identification of GmPHD5 interaction proteins. Histone H3 were pulled down by GST-PHD5 in this experiment as determined by western blotting (A). Silver staining gel of GST-PHD5 pulled down proteins. Proteins only present in the GST-PHD5 pulled down samples were picked out for mass spectrometry analysis (B). Proteins with confident identifications were indicated in the gel (band 1 and 2) (B). Protein 1 and 2 were identified as GmGNAT and GmElongin A by mass spectrometry (see Additional File 3 and 4, Figure S3 and Table S1).