Enables RNA polymerase II-specific DNA-binding transcription factor binding activity. Involved in positive regulation of DNA-binding transcription factor activity and positive regulation of transcription by RNA polymerase II. Part of transcription regulator complex. [provided by Alliance of Genome Resources, Apr 2022] see less Enables RNA polymerase II-specific DNA-binding transcription factor binding activity. Involved in positive regulation of DNA-binding transcription factor activity and positive regulation of transcription by RNA polymerase II. Part of transcription regulator complex. [provided by Alliance of Genome Resources, Apr 2022]