Wolda S L, Glomset J A
Department of Biochemistry, Howard Hughes Medical Institute Laboratory, Seattle, Washington.
J Biol Chem. 1988 May 5;263(13):5997-6000.
Previous work from this laboratory has shown that a derivative of mevalonic acid is post-translationally incorporated into a number of specific proteins in Swiss 3T3 cells. Neither the nature of the modification nor the identities of the modified proteins have been determined to date. Here we describe results concerning modified proteins of approximately 67 kDa from HeLa cells and Chinese hamster ovary cells. We show that these proteins are specific to the nucleus and remain associated with a Triton/salt-insoluble nuclear fraction. Furthermore, immunological studies demonstrate that one of the modified proteins comigrates on two-dimensional gels with lamin B, a structural protein associated with the nuclear envelope. Using antibodies directed against lamin B in an immunoprecipitation experiment, we further show that this mevalonic acid-modified protein specifically coprecipitates with lamin B. These results support the hypothesis that lamin B is modified by a derivative of mevalonic acid.
该实验室之前的研究表明，甲羟戊酸的一种衍生物在翻译后被整合到瑞士3T3细胞中的多种特定蛋白质中。迄今为止，修饰的性质和被修饰蛋白质的身份均未确定。在此，我们描述了关于来自HeLa细胞和中国仓鼠卵巢细胞中约67 kDa修饰蛋白的研究结果。我们发现这些蛋白质是细胞核特有的，并且与Triton/盐不溶性核组分相关联。此外，免疫学研究表明，其中一种修饰蛋白在二维凝胶上与核纤层蛋白B共迁移，核纤层蛋白B是一种与核膜相关的结构蛋白。在免疫沉淀实验中使用针对核纤层蛋白B的抗体，我们进一步表明这种甲羟戊酸修饰的蛋白与核纤层蛋白B特异性共沉淀。这些结果支持了核纤层蛋白B被甲羟戊酸衍生物修饰的假说。
