The sequence between position -42 and -76 base pairs ( bp ) was required for efficient transcription in cells that express alpha 4 , but it showed no activity in HeLa cells , which do not express alpha 4 .
the sequence between position -42 and -76 base pairs ( bp ) was required for efficient transcription in cells that express alpha 4 , but it showed no activity in hela cells , which do not express alpha 4 .
O O O O B-DNA_domain_or_region I-DNA_domain_or_region I-DNA_domain_or_region I-DNA_domain_or_region I-DNA_domain_or_region O O O O O O O O O O O O B-protein_molecule I-protein_molecule O O O O O O O B-cell_line I-cell_line O O O O O B-protein_molecule I-protein_molecule O