Liaoning Key Laboratory of Economic and Applied Entomology, College of Plant Protection, Shenyang Agricultural University, Shenyang 110866, China.
Liaoning Key Laboratory of Economic and Applied Entomology, College of Plant Protection, Shenyang Agricultural University, Shenyang 110866, China.
Cell Rep. 2023 Feb 28;42(2):112102. doi: 10.1016/j.celrep.2023.112102. Epub 2023 Feb 13.
Nutritional symbionts influence host reproduction, but the underlying molecular mechanisms are largely unclear. We previously found that the bacteriocyte symbiont Hamiltonella impacts the sex ratio of the whitefly Bemisia tabaci. Hamiltonella synthesizes folate by cooperation with the whitefly. Folate deficiency by Hamiltonella elimination or whitefly gene silencing distorted whitefly sex ratio, and folate supplementation restored the sex ratio. Hamiltonella deficiency or gene silencing altered histone H3 lysine 9 trimethylation (H3K9me3) level, which was restored by folate supplementation. Genome-wide chromatin immunoprecipitation-seq analysis of H3K9me3 indicated mitochondrial dysfunction in symbiont-deficient whiteflies. Hamiltonella deficiency compromised mitochondrial quality of whitefly ovaries. Repressing ovary mitochondrial function led to distorted whitefly sex ratio. These findings indicate that the symbiont-derived folate regulates host histone methylation modifications, which thereby impacts ovary mitochondrial function, and finally determines host sex ratio. Our study suggests that a nutritional symbiont can regulate animal reproduction in a way that differs from reproductive manipulators.
营养共生体影响宿主繁殖，但潜在的分子机制在很大程度上尚不清楚。我们之前发现，菌胞共生菌 Hamiltonella 会影响粉虱 Bemisia tabaci 的性别比例。Hamiltonella 通过与粉虱合作合成叶酸。Hamiltonella 的消除或粉虱基因沉默会导致叶酸缺乏，从而扭曲粉虱的性别比例，而叶酸补充则会恢复性别比例。Hamiltonella 的缺乏或基因沉默会改变组蛋白 H3 赖氨酸 9 三甲基化（H3K9me3）水平，而叶酸补充则会使其恢复正常。对 H3K9me3 的全基因组染色质免疫沉淀测序分析表明，共生体缺陷的粉虱中线粒体功能障碍。Hamiltonella 的缺乏会损害粉虱卵巢的线粒体质量。抑制卵巢线粒体功能会导致粉虱性别比例扭曲。这些发现表明，共生体衍生的叶酸调节宿主组蛋白甲基化修饰，从而影响卵巢线粒体功能，最终决定宿主的性别比例。我们的研究表明，营养共生体可以以不同于生殖操纵者的方式调节动物繁殖。
