Abstract:
Hairy and Krüppel homolog 1 (Kr-h1) are transcriptional repressors that act synergistically to mediate the gene-repressive action of juvenile hormone (JH). However, whether a regulatory relationship exists between Hairy and Kr-h1 remains unclear. In this study, an inhibitory effect of Hairy on Kr-h1 expression was found. Genetic studies in Drosophila have shown that the simultaneous overexpression of Hairy and Kr-h1 can rescue the defective phenotypes caused by the overexpression of a single factor. Reduced expression of Kr-h1 was observed in Hairy-overexpressing flies and cells, whereas the expression levels of Hairy were unaffected in cells with ectopic expression of Kr-h1. The inhibitory effect of Hairy on Kr-h1 expression was found to occur at the transcriptional level, as Hairy bound directly to the B-box within the Kr-h1 promoter via the bHLH motif and recruited the corepressors C-terminal binding protein (CtBP) and Groucho (Gro) through the PLSLV and WRPW motifs, respectively. Our findings revealed a regulatory relationship between two JH response factors, which advances our understanding of the molecular mechanism of JH signaling.
摘要:
毛状和Krüppel同源物1(Kr-h1)是协同作用以介导幼体激素(JH)的基因抑制作用的转录抑制因子。然而,毛状和Kr-h1之间是否存在调节关系尚不清楚。在这项研究中,发现毛状对Kr-h1表达的抑制作用。果蝇的遗传研究表明,毛状和Kr-h1的同时过表达可以挽救由单因子过表达引起的缺陷表型。在毛状过表达的果蝇和细胞中观察到Kr-h1的表达降低,而Kr-h1异位表达的细胞中毛状表达水平不受影响。毛状对Kr-h1表达的抑制作用发生在转录水平,毛状通过bHLH基序与Kr-h1启动子内的B-box直接结合,并通过PLSLV和WRPW基序招募了C端结合蛋白(CtBP)和Groucho(Gro),分别。我们的发现揭示了两个JH反应因子之间的调节关系,这促进了我们对JH信号的分子机制的理解。