Drosophila homologs of the proto-oncogene product PEBP2/CBF beta regulate the DNA-binding properties of Runt.
Drosophila homologs of the proto-oncogene product PEBP2/CBF beta regulate the DNA-binding properties of Runt.
复制标题
原癌基因产物 PEBP2/CBF beta 的果蝇同源物调节 Runt 的 DNA 结合特性。
DOI：
10.1128/mcb.16.3.932
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发表时间：
1996
影响因子：
5.3
通讯作者：
Gergen,JP
中科院分区：
文献类型：
--
作者：
Golling,G;Li,L;Pepling,M;Stebbins,M;Gergen,JP
果蝇runt基因是转录调节因子Runt结构域家族的创始成员。哺乳动物Runt结构域基因编码异聚DNA结合因子PEBP 2/CBF的α亚基。不相关的PEBP 2/CBFβ蛋白与Runt结构域相互作用以增加其对DNA的亲和力。果蝇Runt蛋白对哺乳动物PEBP 2/CBFβ刺激效应的应答能力的保守性表明果蝇可能具有同源的β蛋白。利用酵母双杂交系统分离与Runt相互作用蛋白的cDNA，我们鉴定出两个与PEBP 2/CBFβ具有实质性序列同源性的果蝇基因，称为Brother和Big-brother。酵母双杂交实验以及体外DNA结合研究证实了Brother、Big-brother和PEBP 2/ CBFβ蛋白的功能同源性，并证明了Runt和Brother蛋白的保守区域是其异二聚体相互作用所必需的。还检查了Runt结构域蛋白在存在和不存在其伴侣的情况下的DNA弯曲特性。我们的研究结果表明，Runt结构域蛋白弯曲DNA，这种弯曲的影响，兄弟蛋白家族成员，支持的想法，异源二聚化与构象变化的Runt结构域。对果蝇胚胎中表达模式的分析表明，Brother和Big-brother可能在体内与Runt相互作用，并进一步表明这些蛋白质的活性不仅限于与Runt的相互作用。
TheDrosophila runtgene is the founding member of the Runt domain family of transcriptional regulators. Mammalian Runt domain genes encode the α subunit of the heteromeric DNA-binding factor PEBP2/CBF. The unrelated PEBP2/CBFβ protein interacts with the Runt domain to increase its affinity for DNA. The conserved ability of theDrosophilaRunt protein to respond to the stimulating effect of mammalian PEBP2/CBFβ indicated that flies were likely to have a homologous β protein. Using the yeast two-hybrid system to isolate cDNAs for Runt-interacting proteins, we identified twoDrosophilagenes, referred to as Brother and Big-brother, that have substantial sequence homology with PEBP2/CBFβ. Yeast two-hybrid experiments as well as in vitro DNA-binding studies confirmed the functional homology of the Brother, Big-brother, and PEBP2/ CBFβ proteins and demonstrated that the conserved regions of the Runt and Brother proteins are required for their heterodimeric interaction. The DNA-bending properties of Runt domain proteins in the presence and absence of their partners were also examined. Our results show that Runt domain proteins bend DNA and that this bending is influenced by Brother protein family members, supporting the idea that heterodimerization is associated with a conformational change in the Runt domain. Analysis of expression patterns inDrosophilaembryos revealed thatBrotherandBig-brotherare likely to interact withruntin vivo and further suggested that the activity of these proteins is not restricted to their interaction with Runt.