{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,17]],"date-time":"2025-12-17T08:32:49Z","timestamp":1765960369191,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,6]],"date-time":"2025-01-06T00:00:00Z","timestamp":1736121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["32360047","32000089"],"award-info":[{"award-number":["32360047","32000089"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The trans-translation system, mediated by transfer-messenger RNA (tmRNA, encoded by the ssrA gene) and its partner protein SmpB, helps to release ribosomes stalled on defective mRNA and targets incomplete protein products for hydrolysis. Knocking out the ssrA and smpB genes in various pathogens leads to different phenotypic changes, indicating that they have both cooperative and independent functionalities. This study aimed to clarify the functional relationships between tmRNA and SmpB in Aeromonas veronii, a pathogen that poses threats in aquaculture and human health. We characterized the expression dynamics of the ssrA and smpB genes at different growth stages of the pathogen, assessed the responses of deletion strains \u0394ssrA and \u0394smpB to various environmental stressors and carbon source supplementations, and identified the gene-regulatory networks involving both genes by integrating transcriptomic and phenotypic analyses. Our results showed that the gene ssrA maintained stable expression throughout the bacterial growth period, while smpB exhibited upregulated expression in response to nutrient deficiencies. Compared to the wild type, both the \u0394ssrA and \u0394smpB strains exhibited attenuated resistance to most stress conditions. However, \u0394ssrA independently responded to starvation, while \u0394smpB specifically showed reduced resistance to lower concentrations of Fe3+ and higher concentrations of Na+ ions, as well as increased utilization of the carbon source \u03b2-Methyl-D-glucoside. The transcriptomic analysis supported these phenotypic results, demonstrating that tmRNA and SmpB cooperate under nutrient-deficient conditions but operate independently in nutrient-rich environments. Phenotypic experiments confirmed that SsrA and SmpB collaboratively regulate genes involved in siderophore synthesis and iron uptake systems in response to extracellular iron deficiency. The findings of the present study provide crucial insights into the functions of the trans-translation system and highlight new roles for tmRNA and SmpB beyond trans-translation.<\/jats:p>","DOI":"10.3390\/ijms26010409","type":"journal-article","created":{"date-parts":[[2025,1,6]],"date-time":"2025-01-06T08:08:52Z","timestamp":1736150932000},"page":"409","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Cooperative and Independent Functionality of tmRNA and SmpB in Aeromonas veronii: A Multifunctional Exploration Beyond Ribosome Rescue"],"prefix":"10.3390","volume":"26","author":[{"given":"Taipeng","family":"Bai","sequence":"first","affiliation":[{"name":"Pathogenesis and Control of Pathogenic Microorganisms Research Team, School of Life and Health Sciences, Hainan Province Key Laboratory of One Health, Collaborative Innovation Center of One Health, Hainan University, Haikou 570228, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juanjuan","family":"Li","sequence":"additional","affiliation":[{"name":"Pathogenesis and Control of Pathogenic Microorganisms Research Team, School of Life and Health Sciences, Hainan Province Key Laboratory of One Health, Collaborative Innovation Center of One Health, Hainan University, Haikou 570228, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xue","family":"Chi","sequence":"additional","affiliation":[{"name":"Pathogenesis and Control of Pathogenic Microorganisms Research Team, School of Life and Health Sciences, Hainan Province Key Laboratory of One Health, Collaborative Innovation Center of One Health, Hainan University, Haikou 570228, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hong","family":"Li","sequence":"additional","affiliation":[{"name":"Pathogenesis and Control of Pathogenic Microorganisms Research Team, School of Life and Health Sciences, Hainan Province Key Laboratory of One Health, Collaborative Innovation Center of One Health, Hainan University, Haikou 570228, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanqiong","family":"Tang","sequence":"additional","affiliation":[{"name":"Pathogenesis and Control of Pathogenic Microorganisms Research Team, School of Life and Health Sciences, Hainan Province Key Laboratory of One Health, Collaborative Innovation Center of One Health, Hainan University, Haikou 570228, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhu","family":"Liu","sequence":"additional","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Animal Nutrition and Feed, Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0103-861X","authenticated-orcid":false,"given":"Xiang","family":"Ma","sequence":"additional","affiliation":[{"name":"Pathogenesis and Control of Pathogenic Microorganisms Research Team, School of Life and Health Sciences, Hainan Province Key Laboratory of One Health, Collaborative Innovation Center of One Health, Hainan University, Haikou 570228, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1234","DOI":"10.1038\/nature08403","article-title":"What Recent Ribosome Structures Have Revealed about the Mechanism of Translation","volume":"461","author":"Schmeing","year":"2009","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Miller, M.R., and Buskirk, A.R. 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