Yorimoto Shunta, Hattori Mitsuru, Kondo Maki, Shigenobu Shuji
Laboratory of Evolutionary Genomics, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan.
Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan.
iScience. 2022 Nov 2;25(12):105478. doi: 10.1016/j.isci.2022.105478. eCollection 2022 Dec 22.
Some hemipteran insects rely on multiple endosymbionts for essential nutrients. However, the evolution of multi-partner symbiotic systems is not well-established. Here, we report a co-obligate symbiosis in the eusocial aphid, . 16S rRNA amplicon sequencing unveiled co-infection with a novel sp. symbiont and , a common obligate endosymbiont in aphids. Both symbionts were housed within distinct bacteriocytes and were maternally transmitted. The and symbionts had streamlined genomes of 432,286 bp and 853,149 bp, respectively, and exhibited metabolic complementarity in riboflavin and peptidoglycan synthesis pathways. These anatomical and genomic properties were similar to those of independently evolved multi-partner symbiotic systems, such as - in Lachninae and aphids, representing remarkable parallelism. Furthermore, symbiont populations and bacteriome morphology differed between reproductive and soldier castes. Our study provides the first example of co-obligate symbiosis in Hormaphidinae and gives insight into the evolutionary genetics of this complex system.
一些半翅目昆虫依靠多种内共生体获取必需营养。然而，多伙伴共生系统的进化尚未明确。在此，我们报道了群居型蚜虫中的一种共同必需共生现象。16S rRNA扩增子测序揭示其与一种新的 属共生体以及蚜虫中常见的必需内共生体 共同感染。两种共生体都存在于不同的含菌细胞中，并通过母体传播。 和 共生体的基因组分别简化为432,286 bp和853,149 bp，并在核黄素和肽聚糖合成途径中表现出代谢互补性。这些解剖学和基因组特性与独立进化的多伙伴共生系统相似，如扁蚜亚科中的 和 蚜虫，呈现出显著的平行性。此外，生殖型和兵蚁型之间的共生体种群和菌胞体形态有所不同。我们的研究提供了扁蚜亚科中共同必需共生的首个例子，并深入了解了这个复杂系统的进化遗传学。
