INRAEAnna Zaidman-Rémy课题组取得一项新突破。他们揭示了细菌管状网络在昆虫共生中引导碳水化合物。这一研究成果发表在2025年10月28日出版的国际学术期刊《细胞》上。
为了研究支持这些交换的机制，研究人员研究了细菌Sodalis pierantonithem与昆虫Sitophilus spp.之间的联系。只吃谷物就能茁壮成长。体积电子显微镜发现，内共生体产生复杂的膜——管状网络（tubenets），连接细菌并大大增加它们与宿主细胞质的交换表面。原位高空间分辨率化学分析表明，管状糖富含碳水化合物，而碳水化合物是细菌为宿主生成营养物质的主要底物。在多细胞生物中描述了有利于营养吸收的多种膜结构。这项工作表明，细菌已经趋同地进化出类似的“生物策略”，通过增加膜界面来增强营养获取。
据了解，共生现象在自然界广泛存在，在生物适应和进化过程中起着重要作用。在营养性内共生中，宿主细胞容纳胞内细菌并充当“代谢工厂”，需要宿主和内共生体之间进行广泛的代谢交换。
附：英文原文
Title: Bacterial tubular networks channel carbohydrates in insect endosymbiosis
Author: Séverine Balmand, Camille Rivard, Sergio Peignier, Rachel Santarella-Mellwig, Meriem Ghanem-Debbache, Justin Maire, Tobias Engl, Mariana Galvo Ferrarini, Elisa Dell’Aglio, Blanca Soriano-Saiz, Charline Dalverny, Veronica La Padula, Petri Turunen, Isabelle Rahioui, Agnès Vallier, Carole Vincent-Monégat, Baptiste Vierne, Nicolas Parisot, Guy Condemine, Pedro Da Silva, Xavier Jaurand, Yannick Schwab, Martin Kaltenpoth, Abdelaziz Heddi, Anna Zaidman-Rémy
Issue&Volume: 2025-10-28
Abstract: Symbiosis is widespread in nature and plays a fundamental role in organism adaptation and evolution. In nutritional endosymbiosis, host cells accommodate intracellular bacteria and act as a “metabolic factory,” requiring extensive metabolic exchanges between host and endosymbiont. To investigate the mechanisms supporting these exchanges, we used the association between the bacterium Sodalis pierantonius and the insect Sitophilus spp. that thrives on an exclusive cereal diet. Volume electron microscopy uncovered that endosymbionts generate complex membranous tubular networks (tubenets) that connect bacteria and drastically increase their exchange surface with the host cytosol. In situ high spatial resolution chemical analysis indicated that tubenets are enriched in carbohydrates, which are the main substrate used by bacteria to generate nutrients for the host. Multiple membranous structures favoring nutrient absorption are described in multicellular organisms. This work demonstrates that bacteria have convergently evolved a similar “biostrategy” that enhances nutrient acquisition by increasing membrane interface.
DOI: 10.1016/j.cell.2025.10.001
Source: https://www.cell.com/cell/abstract/S0092-8674(25)01130-4