Sen A, Todaro G J, Blair D G, Robey W G
Proc Natl Acad Sci U S A. 1979 Aug;76(8):3617-21. doi: 10.1073/pnas.76.8.3617.
Murine sarcoma virus-associated protein kinases that bind to actin have been purified by affinity chromatography on actin coupled to Sepharose. Heat inactivation studies showed the presence of thermolabile enzyme activity in pseudotypes containing a temperature-sensitivity mutant of murine sarcoma virus (MSV) but not in two independent wild-type MSV pseudotypes. Studies with Sephadex G-75 column fractions showed that a low molecular weight form, approximately 15,000, is the major thermolabile kinase in the temperature-sensitive MSV virions. Antibodies raised against the MSV-coded p60 protein, when added to the in vitro reaction mixtures, showed specific phosphorylation of the IgG heavy chain and a simultaneous reduction in the extent of phosvitin phosphorylation catalyzed by the various MSV pseudotype kinases. Thus a transforming retrovirus-coded enzyme activity that interacts directly with a major cytoskeletal protein and whose activity parallels the transforming ability of a conditional MSV mutant has now been identified.
已通过在偶联至琼脂糖凝胶的肌动蛋白上进行亲和层析，纯化出与肌动蛋白结合的鼠肉瘤病毒相关蛋白激酶。热失活研究表明，含有鼠肉瘤病毒（MSV）温度敏感性突变体的假型中存在热不稳定酶活性，而在两种独立的野生型MSV假型中则不存在。用葡聚糖凝胶G - 75柱级分进行的研究表明，一种分子量约为15,000的低分子量形式是温度敏感型MSV病毒粒子中的主要热不稳定激酶。当将针对MSV编码的p60蛋白产生的抗体添加到体外反应混合物中时，显示出IgG重链的特异性磷酸化，同时由各种MSV假型激酶催化的卵黄高磷蛋白磷酸化程度降低。因此，现已鉴定出一种转化逆转录病毒编码的酶活性，该活性直接与一种主要的细胞骨架蛋白相互作用，并且其活性与条件性MSV突变体的转化能力平行。
