Viral gene expression was assayed by the level of p24 gag protein released from cultures transfected with the proviral constructs .
viral gene expression was assayed by the level of p24 gag protein released from cultures transfected with the proviral constructs .
O O O O O O O O O B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group O O O O O O B-other_artificial_source I-other_artificial_source O