Moelling K, Pfaff E, Beug H, Beimling P, Bunte T, Schaller H E, Graf T
Cell. 1985 Apr;40(4):983-90. doi: 10.1016/0092-8674(85)90358-7.
Oncogene protein products from avian myeloblastosis virus, p48v-myb, and from avian leukemia virus E26, p135gag-myb-ets, are located predominantly in the nucleus of nonproducer bone marrow cell clones, as revealed by indirect immunofluorescence. Both oncogene proteins were purified by immunoaffinity chromatography using monoclonal antibodies against p19 and immunoglobulins specific for myb, which was expressed in bacteria for antibody production. The purified proteins bind to DNA in vitro. In contrast, purified p135gag-myb-ets proteins from several mutants of E26 virus, temperature-sensitive for myeloblast transformation, either lost their abilities to bind to DNA or exhibited highly thermolabile DNA-protein interactions in vitro. DNA binding of AMV and E26 oncogene proteins is inhibited by myb-specific immunoglobulins. Our results suggest that lesions in the myb oncogene affect transformation as well as DNA binding of myb proteins in vitro.
间接免疫荧光显示，来自禽成髓细胞瘤病毒的癌基因蛋白产物p48v-myb以及来自禽白血病病毒E26的p135gag-myb-ets主要定位于非生产性骨髓细胞克隆的细胞核中。这两种癌基因蛋白通过免疫亲和层析进行纯化，所用的单克隆抗体针对p19，以及针对在细菌中表达用于抗体生产的myb的特异性免疫球蛋白。纯化后的蛋白在体外可与DNA结合。相比之下，从E26病毒的几个对成髓细胞转化温度敏感的突变体中纯化得到的p135gag-myb-ets蛋白，要么失去了与DNA结合的能力，要么在体外表现出高度热不稳定的DNA-蛋白相互作用。AMV和E26癌基因蛋白与DNA的结合受到myb特异性免疫球蛋白的抑制。我们的结果表明，myb癌基因中的损伤会影响体外转化以及myb蛋白与DNA的结合。
