MiR-210, not let-7, regulates Akt gene expression against Vibrio splendidus infection in the sea cucumber Apostichopus japonicus

• Published in: Fish & shellfish immunology 2024-10, Vol.153, p.109848, Article 109848
• Main Authors: Liu, Li, Ning, Bingyu, Zhan, Yaoyao, Zhao, Tanjun, Chang, Yaqing
• Format: Article
• Language: English
• Subjects: Akt; Animals; Apostichopus japonicus; Gene Expression Regulation - immunology; Immune regulation; Immunity, Innate - genetics; MicroRNAs - genetics; MicroRNAs - immunology; miR-210; Pathogen infection; Proto-Oncogene Proteins c-akt - genetics; Proto-Oncogene Proteins c-akt - immunology; Proto-Oncogene Proteins c-akt - metabolism; Stichopus - genetics; Stichopus - immunology; Stichopus - microbiology; Vibrio - physiology
• ISSN: 1050-4648; 1095-9947; 1095-9947
• DOI: 10.1016/j.fsi.2024.109848

The immune regulatory roles of microRNAs (miRNAs) have recently attracted considerable attention. Bioinformatics prediction revealed that both let-7 and miR-210 provide potential binding sites for the Akt (rac-alpha serine/threonine-protein kinase) gene sequence in the sea cucumber Apostichopus japonicus (termed AjAkt). In this study, we first used a dual-luciferase reporter assay and functional validation techniques to verify the interactions between these two miRNAs (let-7 and miR-210) and AjAkt, and then investigated the functions of the validated miRNA/mRNA pair as part of the innate immune response against Vibrio splendidus infection. We found that AjAkt interacts with miR-210 rather than let-7, and miR-210 negatively regulates the expression of AjAkt. From 8 to 48 h after infection with V. splendidus, opposite trends were observed in the expression levels of miR-210 and AjAkt (mRNA and protein) in coelomocytes, suggesting that the miR-210/AjAkt pair is involved in immune regulation during this period after infection. Both AjAkt silencing and miR-210 overexpression enhanced the phagocytic capacity and reduced the infectivity of A. japonicus after pathogen infection, suggesting that the miR-210/AjAkt pair may regulate the innate immune response of A. japonicus by altering phagocytic capacity. The findings of this study enrich our knowledge of the role of miRNA/mRNA pairs in immune regulation in sea cucumbers and provide insights into the molecular mechanisms of the innate immune response in marine echinoderms. •MiR-210, not let-7, interacts with Akt in Apostichopus japonicus.•MiR-210 overexpression or Akt silencing reduced the prevalence of Vibrio splendidus infection in A. japonicus.•The miR-210/AjAkt pair regulates the innate immune response of A. japonicus by altering phagocytic capacity.