Connolly J A, Kalnins V I, Cleveland D W, Kirschner M W
Proc Natl Acad Sci U S A. 1977 Jun;74(6):2437-40. doi: 10.1073/pnas.74.6.2437.
tau protein isolated from porcine brain microtubules was further purified by electrophoretic elution from polyacrylamide gels and used to prepare antisera in rabbits. The antiserum to tau specifically stains mitotic spindles and a filamentous network within mouse fibroblasts when the indirect immunofluorescence technique is used. The staining of the filamentous network and mitotic spindles is identical to that observed when cells are treated with antiserum prepared against electrophoretically purified tubulin. The filamentous network observed with either serum is sensitive to Colcemid. Absorption of anti-tau serum with electrophoretically purified tubulin does not remove the immunofluorescent staining of the mitotic spindle, whereas absorption with electrophoretically purified tau protein does. Conversely, absorption of antitubulin serum with tubulin eliminates its ability to stain the mitotic spindle, whereas absorption with tau has no effect. We conclude that tau protein and tubulin are antigenically distinct proteins and that tau is an integral part of microtubules in vivo. These results also provide evidence that tau protein, or an antigenically related protein, is associated with microtubules not only in brain but also in other cell types.
从猪脑微管中分离出的tau蛋白通过聚丙烯酰胺凝胶电泳洗脱进一步纯化，并用于在兔体内制备抗血清。当使用间接免疫荧光技术时，tau抗血清可特异性地标记小鼠成纤维细胞内的有丝分裂纺锤体和丝状网络。丝状网络和有丝分裂纺锤体的染色与用针对电泳纯化的微管蛋白制备的抗血清处理细胞时观察到的染色相同。用任何一种血清观察到的丝状网络对秋水仙酰胺敏感。用电泳纯化的微管蛋白吸收抗tau血清并不能消除有丝分裂纺锤体的免疫荧光染色，而用电泳纯化的tau蛋白吸收则可以。相反，用微管蛋白吸收抗微管蛋白血清会消除其标记有丝分裂纺锤体的能力，而用tau吸收则没有效果。我们得出结论，tau蛋白和微管蛋白是抗原性不同的蛋白质，并且tau是体内微管的一个组成部分。这些结果还提供了证据，表明tau蛋白或一种抗原相关蛋白不仅在脑中，而且在其他细胞类型中也与微管相关。
