tokens: The major GC-box binding activity A1 was purified and identified as the transcription factor Sp1 .
folded_tokens: the major gc-box binding activity a1 was purified and identified as the transcription factor sp1 .
labels: O O B-DNA_domain_or_region O O B-protein_molecule O O O O O O B-protein_molecule I-protein_molecule B-protein_molecule O