tokens: HIV-1 proviral DNA contains two binding sites for the transcription factor NF-kappa B .
folded_tokens: hiv-1 proviral dna contains two binding sites for the transcription factor nf-kappa b .
labels: B-virus O O O O B-DNA_domain_or_region I-DNA_domain_or_region O O B-protein_family_or_group I-protein_family_or_group B-protein_molecule I-protein_molecule O