Institute of Molecular Life Sciences, University of Zurich, CH-8057 Zurich, Switzerland.
Genes Dev. 2010 May;24(9):881-6. doi: 10.1101/gad.561310.
Wingless (Wg) signaling regulates expression of its target genes via Pangolin and Armadillo, and their interacting cofactors. In the absence of Wg, Pangolin mediates transcriptional repression. In the presence of Wg, Pangolin, Armadillo, and a cohort of coactivators mediate transcriptional activation. Here we uncover Coop (corepressor of Pan) as a Pangolin-interacting protein. Coop and Pangolin form a complex on DNA containing a Pangolin/TCF-binding motif. Overexpression of Coop specifically represses Wg target genes, while loss of Coop function causes derepression. Finally, we show that Coop antagonizes the binding of Armadillo to Pangolin, providing a mechanism for Coop-mediated repression of Wg target gene transcription.
无翅型（Wg）信号通过穿山甲和装甲蛋白调节其靶基因的表达，以及它们相互作用的协同因子。在没有 Wg 的情况下，穿山甲介导转录抑制。在有 Wg 的情况下，穿山甲、装甲蛋白和一群共激活因子介导转录激活。在这里，我们发现 Coop（穿山甲的共抑制因子）是一种与穿山甲相互作用的蛋白质。Coop 和穿山甲在含有穿山甲/TCF 结合基序的 DNA 上形成复合物。Coop 的过表达特异性抑制 Wg 靶基因，而 Coop 功能丧失导致去抑制。最后，我们表明 Coop 拮抗 Armadillo 与 Pangolin 的结合，为 Coop 介导的 Wg 靶基因转录抑制提供了一种机制。
