Oncogenic Hras-dependent epidermal growth is inhibited following RNAi-mediated depletion of Ctnnb1 and Mllt6. Mus musculus

Genome-wide RNAi screens in mice identified Ctnnb1 and Mllt6 as physiological regulators of HrasG12V-dependent epidermal hyperplasia. To probe the consequences of Ctnnb1 and Mllt6 on HrasG12V-dependent oncogenic growth, we examined how their depletion impacts gene expression in the HrasoncoX2 epidermis. We performed RNA-seq analysis of FACS-purified embryonic epidermal cells, followed by network analysis of differentially regulated transcripts. Whether Ctnnb1 or Mllt6, knockdown markedly enhanced activity of genes restricting growth, and decreased expression of genes promoting epidermal proliferation. This contrasted with known transcriptional changes that typically follow epidermal expression of oncogenic Hras. Moreover, there was a significant overlap in genes whose expression was affected by Mllt6 and β-catenin, further implying a level of shared function. Overall design: Transcriptional profiles of epidermal progenitors of embryonic day 18.5 animals of wild-type, HrasG12V, and HrasG12V depleted of Ctnnb1 or Mllt6 backgrounds.

在小鼠中开展的全基因组RNA干扰（RNAi）筛选已将Ctnnb1与Mllt6鉴定为HrasG12V依赖性表皮增生的生理性调控因子。为探究Ctnnb1与Mllt6对HrasG12V依赖性致癌生长的影响，我们考察了二者敲低对HrasoncoX2表皮细胞基因表达的调控效应。我们对经荧光激活细胞分选（FACS）纯化的胚胎表皮细胞进行了RNA测序（RNA-seq）分析，并对差异调控转录本开展了网络分析。实验结果显示，敲低Ctnnb1或Mllt6均可显著增强生长抑制相关基因的活性，同时下调促表皮增殖基因的表达，这与致癌性Hras在表皮中表达后通常引发的转录变化形成鲜明对比。此外，受Mllt6与Ctnnb1编码的β-连环蛋白（β-catenin）表达影响的基因存在显著重叠，进一步提示二者存在功能共通性。总体实验设计：野生型、HrasG12V突变型，以及HrasG12V背景下敲低Ctnnb1或Mllt6的胚胎第18.5天动物的表皮祖细胞转录谱。