Runx gene family transcription factors play important regulatory roles in metazoan development. The Drosophila genome contains four Runx genes, two of which are well studied (runt and lozenge) and two of which have not been explored in depth yet (CG42267 and CG34145). In the absence of paralog-specific orthologs in vertebrates, we investigated the evolutionary conservation of the Drosophila Runx genes in the genomes of mosquito, red flour beetle, honeybee, and distantly related Bilateria. All four Drosophila Runx genes are conserved in other endopterygote insects. Strikingly, their genetic linkage and genomic arrangement is also highly conserved despite past recombination events in the same genomic region. The preservation of Runx gene cluster organization for at least 300 million years resembles that of insect Hox and selected Wnt genes. We propose a model for the conserved cluster organization of developmental gene family paralogs based on differential coduplication of regulatory elements that act over long distances.

中文翻译：

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昆虫 Runx 基因的保守簇组织。

Runx 基因家族转录因子在后生动物发育中起着重要的调控作用。果蝇基因组包含四个 Runx 基因，其中两个已得到充分研究（runt 和 lozenge），其中两个尚未深入探索（CG42267 和 CG34145）。在脊椎动物中没有旁系同源特异性直系同源物的情况下，我们研究了蚊子、红粉甲虫、蜜蜂和远缘双侧叶虫基因组中果蝇 Runx 基因的进化保守性。所有四个果蝇 Runx 基因在其他内翅目昆虫中都是保守的。引人注目的是，尽管过去在同一基因组区域发生过重组事件，但它们的遗传连锁和基因组排列也高度保守。Runx 基因簇组织至少保存了 3 亿年，类似于昆虫 Hox 和选定的 Wnt 基因。