Yang W M, Inouye C, Zeng Y, Bearss D, Seto E
Moffitt Cancer Center and Research Institute, University of South Florida, Tampa 33612, USA.
Proc Natl Acad Sci U S A. 1996 Nov 12;93(23):12845-50. doi: 10.1073/pnas.93.23.12845.
YY1 is a mammalian zinc-finger transcription factor with unusual structural and functional features. It has been implicated as a positive and a negative regulatory factor that binds to the CCATNTT consensus DNA element located in promoters of many cellular and viral genes. A mammalian cDNA that encodes a YY1-binding protein and possesses sequence homology with the yeast transcriptional factor RPD3 has been identified. A Gal4 DNA binding domain-mammalian RPD3 fusion protein strongly represses transcription from a promoter containing Gal4 binding sites. Association between YY1 and mammalian RPD3 requires a glycine-rich region on YY1. Mutations in this region abolish the interaction with mammalian RPD3 and eliminate transcriptional repression by YY1. These data suggest that YY1 negatively regulates transcription by tethering RPD3 to DNA as a cofactor and that this transcriptional mechanism is highly conserved from yeast to human.
YY1是一种具有独特结构和功能特征的哺乳动物锌指转录因子。它被认为是一种正负调节因子，可与位于许多细胞和病毒基因启动子中的CCATNTT共有DNA元件结合。已鉴定出一种编码与YY1结合蛋白且与酵母转录因子RPD3具有序列同源性的哺乳动物cDNA。Gal4 DNA结合结构域-哺乳动物RPD3融合蛋白强烈抑制含有Gal4结合位点的启动子的转录。YY1与哺乳动物RPD3之间的关联需要YY1上的富含甘氨酸区域。该区域的突变消除了与哺乳动物RPD3的相互作用，并消除了YY1的转录抑制作用。这些数据表明，YY1通过将RPD3作为辅助因子与DNA相连来负调节转录，并且这种转录机制从酵母到人类高度保守。
