Chromosomal localization of the transcription factor YY1 in the mouse and human

2Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 48109-0618, USA Received: 29 September 1993 / Accepted: 29 November 1993 YY1 is a ubiquitously distributed transcription factor be- longing to the GLI-Kr/ippel class of zinc finger proteins. The YY1 cDNA was independently cloned in four differ- ent laboratories from human (Shi et al. 1991; Park and Atchison 1991) and mouse (Hariharan et al. 1991; Flana- gan et al. 1992) tissues. Analysis of these cDNAs revealed that YY1 is highly conserved, showing 98.6% identity be- tween the human and the mouse (Hariharan et al. 1991). Functionally, YY1 is an extremely versatile factor. It has been shown to be a negative regulator in some systems (Shi et al. 1991; Park and Atchison 1991; Lee et al. 1992; Bauknecht et al. 1992; Gumucio et al. 1992; Gualberto et al. 1992), and a positive regulator in others (Riggs et al. 1991; Hariharan et al. 1991). In some systems, the func- tion of YYI as an activator or a repressor is specified by the presence of other proteins (Shi et al. 1991). Finally, YY1 also binds to initiator elements and directs accurate basal transcription