{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T16:48:57Z","timestamp":1786121337636,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T00:00:00Z","timestamp":1785888000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009620","name":"Gansu Provincial Science and Technology Department","doi-asserted-by":"publisher","award":["25JRRK003"],"award-info":[{"award-number":["25JRRK003"]}],"id":[{"id":"10.13039\/501100009620","id-type":"DOI","asserted-by":"publisher"}]},{"award":["25JRRK003"],"award-info":[{"award-number":["25JRRK003"]}],"id":[{"id":"https:\/\/ror.org\/03xz2hx98","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Longnan City Science and Technology Plan Project","award":["No. 2026JY01"],"award-info":[{"award-number":["No. 2026JY01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Insects"],"abstract":"<jats:p>The facultative endosymbiont Serratia symbiotica significantly influences the ecological fitness of its aphid host. However, the molecular mechanisms by which Serratia affects the host\u2019s symbiotic organ, the bacteriocyte, remain poorly understood. Here, we conducted a comparative transcriptomic analysis of bacteriocytes from Serratia\u2212 and Serratia+ pea aphid (Acyrthosiphon pisum) strains. Our analysis revealed that Serratia colonization extensively modulates gene expression within bacteriocytes. Key metabolic pathways were significantly altered: genes involved in ribosomal biogenesis and oxidative phosphorylation were upregulated, while those in fatty acid biosynthesis were downregulated. Furthermore, we observed a complex reshaping of the immune profile, characterized by a broad downregulation of immune recognition and signaling components alongside an upregulation of specific effector genes and antioxidant enzymes. These findings suggest that Serratia induces a state of enhanced anabolic capacity and energy production in bacteriocytes, coupled with strategic reallocation of resources and a finely tuned immune response that balances symbiont tolerance with control. Our RT-qPCR validation confirmed the RNA-seq results, further supporting these results. This study provides the first bacteriocyte-specific transcriptomic resource for the aphid\u2013Serratia interaction system, offering novel insights into the molecular integration of a facultative symbiont into host physiology.<\/jats:p>","DOI":"10.3390\/insects17080815","type":"journal-article","created":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T13:16:29Z","timestamp":1785935789000},"page":"815","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Transcriptional Reshaping of Bacteriocytes in the Aphid\u2013Serratia Symbiosis"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7760-5647","authenticated-orcid":false,"given":"Yaonian","family":"Chen","sequence":"first","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"},{"name":"College of Eco-Environmental Engineering, Qinghai University, Xining 810016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuefeng","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dening","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qing","family":"Dong","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaona","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yifeng","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenbing","family":"Ye","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biological Engineering, Longnan Normal University, Longnan 742500, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"453","DOI":"10.1016\/j.cell.2006.07.014","article-title":"Molecular interactions between bacterial symbionts and their hosts","volume":"126","author":"Dale","year":"2006","journal-title":"Cell"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1146\/annurev-ento-010814-020822","article-title":"Multiorganismal insects: Diversity and function of resident microorganisms","volume":"60","author":"Douglas","year":"2015","journal-title":"Annu. 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