Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK.
J Invertebr Pathol. 2012 Feb;109(2):243-7. doi: 10.1016/j.jip.2011.10.003. Epub 2011 Nov 6.
Many insect species carry inherited Spiroplasma bacteria which act as important partners and antagonists. The nature of symbioses between Spiroplasma and insects has been most extensively studied in the interaction between male-killing Spiroplasma infection and Drosophila melanogaster. For historical reasons, these studies have largely focussed on the Spiroplasma strain known as NSRO, derived from Drosophila nebulosa and transinfected into D. melanogaster. More recently, D. melanogaster naturally infected with Spiroplasma were discovered. Whilst the well studied strain NSRO is closely related to that found natively in D. melanogaster, it is unclear whether strains from D. nebulosa reflect a natural interaction when placed in D. melanogaster. In this paper, we determine if NSRO has similar or different properties from strains of Spiroplasma naturally infecting D. melanogaster in terms of transmission efficiency and the strength and timing of male-killing. Native infections were observed to have higher transmission efficiency than introduced NSRO infections during the early phases of host reproduction, but not during late reproduction. The timing and intensity of male-killing did not differ between infection classes. As a precautionary measure, it is proposed that future work seeking to reveal the nature of coevolved Spiroplasma-Drosophila interactions use the native strain.
许多昆虫物种携带遗传性的螺旋体细菌，这些细菌充当着重要的伙伴和拮抗剂。螺旋体与昆虫之间共生关系的本质在雄性致死螺旋体感染和黑腹果蝇之间的相互作用中得到了最广泛的研究。由于历史原因，这些研究主要集中在源自果蝇 nebuloza 并转染到黑腹果蝇中的 NSRO 螺旋体菌株上。最近，发现了自然感染螺旋体的黑腹果蝇。虽然经过充分研究的 NSRO 菌株与在黑腹果蝇中发现的天然菌株密切相关，但尚不清楚来自果蝇 nebuloza 的菌株在放入黑腹果蝇中时是否反映了自然相互作用。在本文中，我们确定 NSRO 在传播效率以及雄性致死的强度和时机方面与自然感染黑腹果蝇的螺旋体菌株是否具有相似或不同的特性。在宿主繁殖的早期阶段，与引入的 NSRO 感染相比，自然感染具有更高的传播效率，但在后期繁殖中则不然。感染类型之间的雄性致死的时机和强度没有差异。作为预防措施，建议未来旨在揭示共同进化的螺旋体-果蝇相互作用本质的工作使用天然菌株。
