However , other transcription factors or coactivators of NF-kappa B are required for tax activation but these remain to be identified .
however , other transcription factors or coactivators of nf-kappa b are required for tax activation but these remain to be identified .
O O O B-protein_family_or_group I-protein_family_or_group O O O B-protein_molecule I-protein_molecule O O O B-protein_molecule O O O O O O O O