Activation of MHC class II promoters requires binding of at least three distinct multi-protein complexes ( RFX , X2BP and NF-Y ) .
activation of mhc class ii promoters requires binding of at least three distinct multi-protein complexes ( rfx , x2bp and nf-y ) .
O O B-cell_type I-cell_type I-cell_type O O O O O O O O B-protein_complex I-protein_complex O B-protein_complex O B-protein_complex O B-protein_complex O O