Analysis of Tax mutants showed that two mutants , IEXC29S and IEXL320G , were unable to significantly transactivate the c-sis/PDGF-B promoter .
analysis of tax mutants showed that two mutants , iexc29s and iexl320g , were unable to significantly transactivate the c-sis/pdgf-b promoter .
O O B-protein_molecule O O O O O O B-protein_molecule O B-protein_molecule O O O O O O O B-protein_molecule O O