Wang Zhengyan, Yong Hanzi, Zhang Shan, Liu Zhiyuan, Zhao Yaru
School of Food and Strategic Reserves, Henan University of Technology, Zhengzhou 450001, China.
School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China.
Insects. 2023 Jun 30;14(7):594. doi: 10.3390/insects14070594.
The symbiotic microbiome is critical in promoting insect resistance against colonization by exogenous microorganisms. The mechanisms by which symbionts contribute to the host's immune capacity is referred to as colonization resistance. Symbionts can protect insects from exogenous pathogens through a variety of mechanisms, including upregulating the expression of host immune-related genes, producing antimicrobial substances, and competitively excluding pathogens. Concordantly, insects have evolved fine-tuned regulatory mechanisms to avoid overactive immune responses against symbionts or specialized cells to harbor symbionts. Alternatively, some symbionts have evolved special adaptations, such as the formation of biofilms to increase their tolerance to host immune responses. Here, we provide a review of the mechanisms about colonization resistance of symbionts in their insect hosts. Adaptations of symbionts and their insect hosts that may maintain such symbiotic relationships, and the significance of such relationships in the coevolution of symbiotic systems are also discussed to provide insights into the in-depth study of the contribution of symbionts to host physiology and behavior.
共生微生物群落在促进昆虫抵抗外源微生物定殖方面至关重要。共生体促进宿主免疫能力的机制被称为定殖抗性。共生体可以通过多种机制保护昆虫免受外源病原体侵害，包括上调宿主免疫相关基因的表达、产生抗菌物质以及竞争性排斥病原体。相应地，昆虫已经进化出精细调节的机制，以避免对共生体产生过度活跃的免疫反应，或者进化出专门的细胞来容纳共生体。或者，一些共生体已经进化出特殊的适应性，比如形成生物膜以提高它们对宿主免疫反应的耐受性。在这里，我们综述了共生体在其昆虫宿主中的定殖抗性机制。还讨论了共生体及其昆虫宿主可能维持这种共生关系的适应性，以及这种关系在共生系统共同进化中的意义，以便为深入研究共生体对宿主生理和行为的贡献提供见解。
