YY1: Proteins and Enzymes

Yin-Yang 1 is a ubiquitous zinc-finger transcription factor that belongs to the Polycomb group of proteins. In addition to its ability to initiate transcription, YY1 contains one N-terminal transcription activation motif and one C-terminal transcription repression domain. Its dual nature is context specific, and this gives rise to its Yin (shady)-Yang (sunny) complementary opposites designation. It is involved in cell proliferation, differentiation and tumorigenesis.