A biotin-labeled MET-G4-forming sequence was used as bait to capture proteins binding to MET-G4. In contrast, a biotin-labeled MET-G4-MUT sequence served as a control bait to exclude non-specific DNA-binding proteins. After incubation with cell lysate from HepG2 cells, the biotin-labeled sequences were immobilized on avidin agarose beads for protein enrichment. Subsequently, the enriched proteins were separated by SDS-PAGE gel electrophoresis and then subjected to LC-MS/MS analysis.