【摘要】 克隆得到了大黄鱼cd22(Larimichthys crocea cd22,Lccd22)的基因序列。其ORF全长含1941个核苷酸，编码646个氨基酸，具有典型的I型膜蛋白结构和特征性的CD22蛋白结构域，N端有20个氨基酸组成的信号肽，胞质区内有2个Ig超家族结构域、2个Ig C2结构域和1个Ig-like结构域，胞质尾部有两个酪氨酸免疫受体抑制基序ITIM。大黄鱼cd22基因具有20个外显子和19个内含子，在染色体上与scx和hpn等基因相邻。大黄鱼cd22 mRNA在体外分离培养的原代IgM~+ B淋巴细胞和粒细胞中转录水平较高。在大肠杆菌中重组表达并纯化获得了重组大黄鱼cd22去信号肽胞外段，利用其制备了特异性抗大黄鱼Cd22的多克隆抗体，该抗体可识别体外分离培养的原代大黄鱼头肾淋巴细胞表面的天然Cd22蛋白。更多还原

【Abstract】 In this study, the large yellow croaker cd22(Larimichthys crocea cd22,Lccd22) was cloned and characterized.The open reading frame(ORF) of Lccd22 contains 1941 nucleotides, encoding a protein with 646 amino acids.The Lccd22 exhibited a typical structure of type I transmembrane protein as well as the characteristic CD22 signature motif with a signal peptide, a transmembrane domain, an intracellular region containing two Ig domains, two Ig C2 domains and an Ig-like domain.In the cytoplasmic tail, there are two conserved typical immunoreceptor tyrosine-based inhibitory motifs(ITIMs).The Lccd22 shares a similar genomic structure and gene synteny with other teleost cd22,but are quite different from that of mammalian CD22.The mRNA of Lccd22 was highly transcribed in in vitro cultured primary granulocytes and IgM~+ B lymphocytes.The recombinant Lccd22 was expressed, purified in E.coli and was used as antigen to produce the specific polyclonal antibody against LcCd22,which could recognize the native LcCd22 on the membrane of in vitro cultured primary head kidney lymphocytes.更多还原