Galectins, a family of evolutionary conserved β-galactoside-binding proteins, have been characterized in a wide range of species. Many reports have indicated vital roles of galectins in innate immunity, especially in the mucosal tissues against infection. However, the systematic identification of galectin gene family is still lacking in teleost. Here, we characterized the galectin gene family and investigated their expression profiles post bacterial challenge in turbot (Scophthalmus maximus L.). In this study, a total of 13 galectin genes were characterized in turbot, phylogenetic analyses revealed their strong relationships to half smooth tongue sole and puffer fish, and syntenic analyses confirmed the orthology suggested by the phylogenetic analysis. In addition, the copy number of galectin genes is similar across a broad spectrum of species from fish to amphibians, birds, and mammals, ranging from 8 to 16 genes. Furthermore, the galectin genes were widely expressed in all the examined turbot tissues, and most of the galectin genes were strongly expressed in mucosal tissues (skin, gill and intestine). Moreover, majority of the galectin genes were significantly regulated after Vibrio anguillarum infection in the intestine, gill and skin, suggesting that galectins were involved in the mucosal immune response to V. anguillarum infection in turbot. In addition, subcellular localization analysis showed lgals3a was distributed in the cytoplasm and nucleus. However, the knowledge of galectins are still limited in teleost species, further studies should be carried out to better characterize its detailed roles in teleost mucosal immunity.

半乳凝素是进化保守的β-半乳糖苷结合蛋白家族，已在许多物种中得到鉴定。许多报道表明半乳凝集素在先天免疫中，特别是在抵抗感染的粘膜组织中起着至关重要的作用。但是，硬骨动物中仍缺乏对半乳凝素基因家族的系统鉴定。在这里，我们表征了半乳糖凝集素基因家族，并研究了细菌在大菱t中的表达特征（Scophthalmus maximusL.）。在这项研究中，共鉴定了13种半乳糖凝集素基因，系统发育分析表明它们与半光滑的舌和河豚有很强的关系，并且同系分析证实了系统发育分析所建议的正交性。此外，从鱼类到两栖动物，鸟类和哺乳动物的广泛物种中，半乳凝素基因的拷贝数相似，范围为8至16个基因。此外，半乳凝素基因在所有被检查的菱形组织中广泛表达，并且大多数半乳凝素基因在粘膜组织（皮肤，腮和肠）中强烈表达。而且，大多数半乳糖凝集素基因在鳗弧菌后得到显着调节。肠，腮和皮肤的感染，表明半乳糖凝集素参与了大菱t对鳗弧菌感染的粘膜免疫反应。此外，亚细胞定位分析显示lgals3a分布在细胞质和细胞核中。但是，半乳凝集素的知识在硬骨鱼种中仍然有限，应该进行进一步的研究以更好地表征其在硬骨鱼粘膜免疫中的详细作用。