Laboratory of Marine Life Science and Technology, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, PR China.
Fish Shellfish Immunol. 2013 Jun;34(6):1496-504. doi: 10.1016/j.fsi.2013.03.350. Epub 2013 Mar 28.
Ubiquitin-conjugating enzymes (UBE2s or E2s) are characterized by the presence of a highly conserved ubiquitin-conjugating (UBC) domain, which predominantly determines the type of ubiquitin chains and directly controls the cellular fate of the substrate. In this study, an E2 homolog was identified and functionally characterized in abalone, which we named ab-UBE2D. The full-length cDNA consists of 1005 bp with an ORF encoding a protein of 147 amino acids. The deduced amino acid sequence shows ab-UBE2D shares conserved UBC domain with other E2 proteins and belongs to class I E2 enzyme family, which are further confirmed by phylogenetic tree analysis. Real-time PCR and western blot analyses showed that ab-UBE2D was ubiquitously expressed in abalone and the expression level of ab-UBE2d was significantly induced by LPS and Poly (I:C). Immunofluorescence microscopy staining demonstrated that native ab-UBE2D was mainly distributed in the cytoplast. Ubiquitination assay showed that ab-UBE2D had ubiquitin conjugating activity to form the enzyme-(Ub)n conjugates. Taken together, these results strongly suggest that ab-UBE2D is an E2 homolog and it may be involved in the immune response of abalone, Haliotis diversicolor supertexta.
泛素连接酶（UBE2s 或 E2s）的特征是存在高度保守的泛素连接（UBC）结构域，该结构域主要决定泛素链的类型，并直接控制底物的细胞命运。在这项研究中，在鲍鱼中鉴定并功能表征了一种 E2 同源物，我们将其命名为 ab-UBE2D。全长 cDNA 由 1005bp 组成，ORF 编码 147 个氨基酸的蛋白质。推导的氨基酸序列显示 ab-UBE2D 与其他 E2 蛋白共享保守的 UBC 结构域，并且属于 I 类 E2 酶家族，这通过系统发育树分析进一步得到证实。实时 PCR 和 Western blot 分析表明，ab-UBE2D 在鲍鱼中广泛表达，ab-UBE2d 的表达水平被 LPS 和 Poly（I:C）显著诱导。免疫荧光显微镜染色表明，天然 ab-UBE2D 主要分布在细胞质中。泛素化测定表明 ab-UBE2D 具有泛素连接酶活性，可形成酶-(Ub)n 缀合物。综上所述，这些结果强烈表明 ab-UBE2D 是一种 E2 同源物，它可能参与了鲍鱼，Haliotis diversicolor supertexta 的免疫反应。
