Arabidopsis Wdr8 interactors identification

To identify Arabidopsis Wdr8 interactors, immunoprecipitation associated LC-MS/MS analysis was carried out. Crude proteins extracted from Wdr8-GFP expressing transgenic plants was subjected to the immuno-precipitation assay using GFP antibody magnetic beads (µMACS GFP isolation kit, Miltenyi Biotec). Co-purified proteins were separated by 10% SDS-PAGE gel and stained with SYPRO Ruby (BioRad laboratories). The stained protein bands were excised into several fraction pieces according to protein sizes, and in-gel protein digestion by trypsin was carried out. Purified protein peptides were subjected to LC-MS/MS analysis (LTQ-Orbitrap XL-HTC-PAL system). Collected MS/MS peak spectra was analyzed by the MASCOT server to identify peptide sequence.