小鼠泛素结合酶UBE2W的抗体制备及组织表达谱分析

Generation of Mouse UBE2W Antibody and Analysis of UBE2W Expression in Mouse Tissues

泛素结合酶(E2)是蛋白泛素化修饰所需的第二个连接酶,在泛素转移和底物特异性识别过程中发挥着重要作用。UBE2W是一种新发现的E2酶,其果蝇属同源蛋白可能在光转导或视网膜变性过程中发挥作用,鼠和人同源蛋白功能未见报道。生物信息学分析UBE2W鼠源氨基酸序列,发现UBE2W具有典型的UBC结构域并在多种物种高度保守。通过构建UBE2W原核表达质粒,在大肠杆菌中表达并纯化了GST-UBE2W融合蛋白。以此纯化蛋白作为抗原免疫新西兰白兔制备抗UBE2W多抗血清,并利用制备的UBE2W抗原柱亲和纯化UBE2W多抗。为了检测纯化抗体特异性,在真核细胞中瞬时表达了myc-UBE2W融合蛋白,分别用myc单抗和UBE2W多抗进行Western blotting分析,结果表明获得了特异性的UBE2W抗体。利用此特异性抗体在小鼠脑、心脏、肾脏、肝脏、肺、肌肉、脾脏和睾丸等组织中均检测到了UBE2W的表达,且在小鼠睾丸中成年期表达最高。

Ubiquitin conjugating enzyme functions as the second enzyme required for protein ubiquitination and plays an important role in ubiquitin transferring and substrate specific recognition. UBE2W, a newly described member of E2 family, was formerly reported probably involving in phototransduction or retinal degeneration in Drosophila. In this study, we report that murine UBE2W harbors a typical UBC domain and is highly conserved in different vertebrate homologues. GST-tagged UBE2W was expressed in E. coil BL21 （DE3） and purified with GST affinity chromatography. Using this antigen, we generated and further separated rabbit polyclonal antibody of UBE2W, of which the activity and specificity were confirmed by immunoblotting of transiently expressed myc-UBE2W fusion protein. Wide expression of UBE2W was found in brain, muscle, heart, lung, liver, spleen, kidney and testis of mouse with the generated antibody, indicating the functional importance of this novel protein. Furthermore, the UBE2W highly expression was confined to the adult testis and was developmental stage-specific.