程序性细胞死亡（细胞凋亡）的主要功能之一是去除发生致癌突变的细胞，从而防止癌变。通过利用我们实验室制造的双头 EP (DEP) 转座子（一种 P 元件衍生物），我们在果蝇中进行了插入诱变筛选，以鉴定当过度表达时抑制 p53 激活的细胞凋亡的基因。 DEP 元件两端都有 Gal4 可激活的外向 UAS 启动子，可在体内单独删除。在 DEP 插入突变体中，我们使用 GMR-Gal4 驱动程序诱导两个 UAS 启动子的转录，并测试了对激活的 UAS-p53 转基因产生的凋亡粗糙眼表型的抑制效果。通过 DEP 插入，鉴定出 7 个基因可抑制 p53 诱导的细胞凋亡。在四种突变体中，抑制效应是由一个 UAS 启动子（Pka-R2、Rga、crol、Spt5）激活的单个基因引起的。在其他三个（Orct2、Polr2M、stg）中，删除任一 UAS 启动子都会消除抑制效果。在qPCR实验中，我们发现DEP插入附近的基因也表现出表达水平升高。这表明附近基因对抑制细胞凋亡有累加作用。在真核基因组中存在共表达的基因簇。其中包括三个 DEP 插入突变体，其中两个位于单独的共表达基因簇附近。这提出了这样的可能性：这些簇中的某些基因的活性可能有助于抑制细胞凋亡。© 作者 2024。由牛津大学出版社代表美国遗传学会出版。

One of a major function of programmed cell death (apoptosis) is the removal of cells which suffered oncogenic mutations, thereby preventing cancerous transformation. By making use of a Double-Headed-EP (DEP) transposon, a P element derivative made in our laboratory, we made an insertional mutagenesis screen in Drosophila melanogaster to identify genes which, when overexpressed, suppress the p53-activated apoptosis. The DEP element has Gal4-activatable, outward-directed UAS-promoters at both ends which can be deleted separately in vivo. In the DEP insertion mutants, we used the GMR-Gal4 driver to induce transcription from both UAS-promoters and tested the suppression effect on the apoptotic rough eye phenotype generated by an activated UAS-p53 transgene. By DEP insertions, seven genes were identified which suppressed the p53-induced apoptosis. In four mutants, the suppression effect resulted from single genes activated by one UAS-promoter (Pka-R2, Rga, crol, Spt5). In the other three (Orct2, Polr2M, stg), deleting either UAS-promoter eliminated the suppression effect. In qPCR experiments we found that the genes in the vicinity of the DEP insertion also showed an elevated expression level. This suggested an additive effect of the nearby genes on suppressing apoptosis. In the eucaryotic genomes there are co-expressed gene clusters. Three of the DEP insertion mutants are included and two are in close vicinity of separate co-expressed gene clusters. This raises the possibility that the activity of some of the genes in these clusters may help the suppression of the apoptotic cell death.© The Author(s) 2024. Published by Oxford University Press on behalf of The Genetics Society of America.