Harumoto Toshiyuki, Moriyama Minoru, Fukatsu Takema
Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan.
Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
Naturwissenschaften. 2025 Apr 29;112(3):34. doi: 10.1007/s00114-025-01986-0.
Many insects have symbiotic microorganisms within their body. Such microbial symbiosis underpins the survival and prosperity of insects through multiple means. The brown-winged green stinkbug Plautia stali, which is notorious as an agricultural pest and utilized as an experimental model insect, harbors a bacterial symbiont Pantoea in a posterior part of the midgut, which is essential for the host's development and reproduction. From both basic and applied research perspectives, it is important to investigate the mechanistic bases underpinning the insect-microbe symbiotic association. Here, we performed detailed electron and optical microscopic analyses of the early nymphal midguts to reveal the type of cellular structure and property that orchestrates the symbiont colonization in the restricted part of the midgut. We identified two peculiar structural features of the nymphal midgut that develop in a region-restricted manner: long and heterogenous cellular protrusions (microvilli) solely emerged in the midgut symbiotic region and highly developed circular muscle cell layers specifically observed in the junction of non-symbiotic and symbiotic regions of the midgut. We discuss the potential roles of these unique structures in the midgut bacterial symbiosis.
许多昆虫体内都有共生微生物。这种微生物共生关系通过多种方式支撑着昆虫的生存和繁衍。茶色绿蝽（Plautia stali）作为一种农业害虫而臭名昭著，同时也是一种实验模式昆虫，它在中肠后部含有一种细菌共生体泛菌（Pantoea），这对宿主的发育和繁殖至关重要。从基础研究和应用研究的角度来看，研究昆虫与微生物共生关系的机制基础都很重要。在这里，我们对若虫早期的中肠进行了详细的电子显微镜和光学显微镜分析，以揭示在中肠受限部位协调共生体定殖的细胞结构类型和特性。我们确定了若虫中肠以区域受限方式发育的两个独特结构特征：仅在中肠共生区域出现的长且异质的细胞突起（微绒毛），以及在中肠非共生区域和共生区域交界处特别观察到的高度发达的环形肌细胞层。我们讨论了这些独特结构在中肠细菌共生中的潜在作用。
