REGULATION OF TRANSCRIPTION BY DIMERIZATION OF ERYTHROID FACTOR NF-E2 P45 WITH SMALL MAF PROTEINS
REGULATION OF TRANSCRIPTION BY DIMERIZATION OF ERYTHROID FACTOR NF-E2 P45 WITH SMALL MAF PROTEINS
复制标题
DOI：
10.1038/367568a0
复制
发表时间：
1994-02-10
期刊：
影响因子：
64.8
通讯作者：
YAMAMOTO, M
中科院分区：
文献类型：
--
作者：
IGARASHI, K;KATAOKA, K;YAMAMOTO, M
转录因子NF-E2在调节红细胞特异性基因表达中起关键作用。NF-E2 p45蛋白的克隆表明，它含有一个基本区域-亮氨酸拉链（b-zip）结构域，该结构域与另一个未知蛋白（相对分子质量为18,000）结合形成功能性NF-E2（参考文献2）。我们在这里表明，maf原癌基因家族3-5的产物，MafF， MafG和MafK （maf小蛋白）具有b-zip dna结合结构域，但缺乏典型的转激活结构域3，通过与p45的异二聚体结合直接控制p45的dna结合特性。小Maf蛋白的同型二聚体作为负调节因子，而由Maf和p45组成的异源二聚体在体内支持主动转录。这些结果表明，一个（或全部）小Maf蛋白是NF-E2活性所需的第二个组成链，并且根据红细胞内p45和Maf蛋白的平衡浓度，NF-E2位点可以实现负调控和正调控。
TRANSCRIPTION factor NF-E2 is crucial for regulating erythroid-specific gene expression1. Cloning of the NF-E2 p45 protein has revealed that it contains a basic region-leucine zipper (b-zip) domain which associates with another unidentified protein (of relative molecular mass 18,000) to form functional NF-E2 (ref. 2). We show here that products of the maf proto-oncogene family3-5, MafF, MafG and MafK (the small Maf proteins) which possess a b-zip DNA-binding domain but lack a canonical transactivation domain3, directly control the DNA-binding properties of p45 by heterodimeric association with p45. Whereas homodimers of the small Maf proteins act as negative regulators, heterodimers composed of Maf and p45 support active transcription in vivo. These results indicate that one (or all) of the small Maf proteins is the second constituent chain required for NF-E2 activity, and that negative as well as positive regulation can be achieved through an NF-E2 site, depending on the equilibrium concentrations of p45 and the Maf proteins inside erythroid cells.