negative cofactor 2 complex GO:0017054 A heterodimeric protein complex that can stably associate with TATA-binding protein on promoters, thereby preventing the assembly of transcription factors TFIIA and TFIIB and leading to repression of RNA polymerase II transcription. The two subunits, NC2alpha (Drap1) and NC2beta (Dr1), dimerize through histone fold domains of the H2A/H2B type present in the amino termini. cellular_component RNA polymerase II transcription repressor complex