tokens: The natural dominant negative HLH factor Id3 , which blocks transcriptional activity of a number of known bHLH factors , was expressed in CD34+ progenitor cells by retrovirus-mediated gene transfer .
folded_tokens: the natural dominant negative hlh factor id3 , which blocks transcriptional activity of a number of known bhlh factors , was expressed in cd34+ progenitor cells by retrovirus-mediated gene transfer .
labels: O O B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group B-protein_molecule O O O B-other_name I-other_name O O O O O B-protein_family_or_group I-protein_family_or_group O O O O B-cell_type I-cell_type I-cell_type O O O O O