Quinlan R A, Franke W W
Proc Natl Acad Sci U S A. 1982 Jun;79(11):3452-6. doi: 10.1073/pnas.79.11.3452.
Certain smooth muscle cells of blood vessel walls as well as cultured baby hamster kidney cells contain simultaneously two different intermediate-sized filament (IF) proteins, desmin and vimentin. We have examined the question of the occurrence of both proteins in the same IF by chemically crosslinking the single cysteine group present in each of them. Oxidative crosslinking of filaments present in cytoskeletal preparations with cupric ion complexes of 1,10-phenanthroline resulted in formation of three types of dimers: vimentin-vimentin, desmin-desmin, and vimentin-desmin. These dimers were separated by NaDodSO4/polyacrylamide gel electrophoresis and characterized by binding of specific antibodies, by one- and two-dimensional gel electrophoresis of monomers obtained after cleavage of the disulfide bond by thiol agents, and by mapping of radioiodinated tryptic peptides. The demonstration of heterodimers of vimentin and desmin in vascular smooth muscle tissue of cow and chicken and in baby hamster kidney cells shows that the two proteins can be integrated in the same IF and can be nearest neighbors, oriented with their cysteine residues in a mirror-image symmetry. The possible existence of heteropolymer IF in other cell types is discussed.
血管壁的某些平滑肌细胞以及培养的幼仓鼠肾细胞同时含有两种不同的中间丝（IF）蛋白，即结蛋白和波形蛋白。我们通过化学交联它们各自所含的单个半胱氨酸基团，研究了这两种蛋白是否存在于同一中间丝中的问题。用1,10 - 菲咯啉的铜离子络合物对细胞骨架制剂中的细丝进行氧化交联，产生了三种类型的二聚体：波形蛋白 - 波形蛋白、结蛋白 - 结蛋白和波形蛋白 - 结蛋白。这些二聚体通过十二烷基硫酸钠/聚丙烯酰胺凝胶电泳分离，并通过特异性抗体结合、用硫醇试剂裂解二硫键后得到的单体的一维和二维凝胶电泳以及放射性碘化胰蛋白酶肽图谱进行表征。在牛和鸡的血管平滑肌组织以及幼仓鼠肾细胞中证明波形蛋白和结蛋白的异源二聚体表明，这两种蛋白可以整合到同一中间丝中，并且可以是紧邻的，其半胱氨酸残基呈镜像对称排列。文中还讨论了异源聚合物中间丝在其他细胞类型中可能存在的情况。
