Department of Biological Sciences, Vanderbilt University, Nashville, United States.
Department of Molecular Biosciences, University of Kansas, Lawrence, United States.
Elife. 2021 Oct 22;10:e67686. doi: 10.7554/eLife.67686.
are the most widespread bacterial endosymbionts in animals. Within arthropods, these maternally transmitted bacteria can selfishly hijack host reproductive processes to increase the relative fitness of their transmitting females. One such form of reproductive parasitism called male killing, or the selective killing of infected males, is recapitulated to degrees by transgenic expression of the prophage () gene. Here, we characterize the genotype-phenotype landscape of induced male killing in using transgenic expression. While phylogenetically distant homologs induce no sex-ratio bias, closely-related homologs exhibit complex phenotypes spanning no death, male death, or death of all hosts. We demonstrate that alternative start codons, synonymous codons, and notably a single synonymous nucleotide in can ablate killing. These findings reveal previously unrecognized features of transgenic -induced killing and establish new hypotheses for the impacts of post-transcriptional processes in male killing variation. We conclude that synonymous sequence changes are not necessarily silent in nested endosymbiotic interactions with life-or-death consequences.
是动物中最广泛分布的细菌内共生体。在节肢动物中，这些通过母系遗传的细菌可以自私地劫持宿主的生殖过程，从而提高其传播雌性的相对适应性。这种形式的生殖寄生称为雄性致死，或感染雄性的选择性致死，通过转基因组表达噬菌体 () 基因在一定程度上被重现。在这里，我们使用转基因表达来描述在诱导雄性致死中的基因型-表型景观。虽然系统发育上遥远的 同源物不会引起性别比例偏差，但密切相关的同源物表现出跨越无死亡、雄性死亡或所有宿主死亡的复杂表型。我们证明了替代起始密码子、同义密码子，特别是 中的单个同义核苷酸可以消除致死性。这些发现揭示了以前未被认识到的转基因为诱导致死的特征，并为雄性致死变异中翻译后过程的影响提出了新的假设。我们的结论是，同义序列变化在与生死攸关的嵌套内共生相互作用中不一定是沉默的。
