SDS-PAGE, protein staining, lectin blotting, and Western blotting

Proteins were separated by 5–20% SDS-PAGE. Silver staining and GelCode Blue staining were performed using Silver Stain II Kit Wako (FUJIFILM) and GelCode Blue Safe Protein Stain (ThermoFisher Scientific), respectively, in accordance with the manufacturers’ protocols. For lectin and Western blotting, proteins separated by SDS-PAGE were transferred to a nitrocellulose membrane, followed by blocking with TBS-T containing 1% BSA (for lectin blotting) or TBS-T containing 5% skim milk (for Western blotting). For lectin blotting, the membranes were incubated with HRP-conjugated lectin that had been diluted with 1% BSA in TBS-T. For Western blotting, the membranes were incubated with primary and HRP-conjugated secondary antibodies that had been diluted with 5% skim milk in TBS-T. Signals were detected with Western Lightning Plus-ECL (PerkinElmer) or SuperSignal West Femto Maximum Sensitivity substrate (Thermo Fisher Scientific) using FUSION-SOLO 7 s EDGE (Vilber-Lourmat).