Bushmeyer S, Park K, Atchison M L
Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104, USA.
J Biol Chem. 1995 Dec 15;270(50):30213-20. doi: 10.1074/jbc.270.50.30213.
YY1 is a multifunctional transcription factor capable of either activation or repression of transcription. Using a series of mutant proteins, we have characterized domains responsible for activation or repression. We found that the YY1 transcriptional activation domain lies near the amino terminus and requires amino acids 16-29 and 80-100 for maximal activity. The region between residues 16 and 29 has the potential to form an acidic amphipathic helix, whereas residues between 80 and 100 are rich in proline and glutamine. The YY1 repression domain lies near the carboxyl terminus and is embedded within the YY1 zinc finger region necessary for binding to DNA. Deletion of YY1 amino acids, which include zinc fingers 3 and 4, abolishes repression. However, site-directed mutagenesis, progressive deletion, and internal deletion mutant analyses indicate that the normal structures of zinc fingers 3 and 4 are not required for repression.
YY1是一种多功能转录因子，能够激活或抑制转录。我们利用一系列突变蛋白，对负责激活或抑制的结构域进行了表征。我们发现，YY1转录激活结构域位于氨基末端附近，最大活性需要氨基酸16 - 29和80 - 100。16至29位残基之间的区域有可能形成酸性两亲性螺旋，而80至100位残基富含脯氨酸和谷氨酰胺。YY1抑制结构域位于羧基末端附近，并嵌入到与DNA结合所必需的YY1锌指区域内。删除包括锌指3和4在内的YY1氨基酸会消除抑制作用。然而，定点诱变、逐步缺失和内部缺失突变分析表明，抑制作用并不需要锌指3和4的正常结构。
