Prasad S C, Thraves P J, Kuettel M R, Srinivasarao G Y, Dritschilo A, Soldatenkov V A
Department of Radiation Medicine, Division of Radiation Research, Vincent T. Lombardi Cancer Center, Georgetown University Medical Center, Washington, DC 20007, USA.
Biochem Biophys Res Commun. 1998 Aug 19;249(2):332-8. doi: 10.1006/bbrc.1998.9137.
Vimentin intermediate filaments (IF) are responsible for regulation of cell attachment and subcellular organization. Using an in vitro model system of human prostate epithelial cells (267B1-XR), we demonstrate that a series of vimentin proteolytic fragments represent some of the differentially expressed proteins in 2D-gel profiles of the apoptotic cells undergoing ionizing radiation-induced cell death. A caspase-sensitive motif search suggests that the type III IF protein (vimentin) is subject to proteolysis to promote the execution phase of apoptosis, in a manner similar to the well-established type V (lamins) and type I (keratins 18, 19) IF proteins. Furthermore, vimentin and a few of its derived polypeptides, reported to be specific to the apoptotic process, correspond to ubiquinated proteins, thus pointing to the complex interrelationships of protein ubiquination in solubilizing the IF network during apoptosis.
波形蛋白中间丝（IF）负责调节细胞黏附和亚细胞组织。利用人前列腺上皮细胞（267B1-XR）的体外模型系统，我们证明一系列波形蛋白蛋白水解片段代表了经历电离辐射诱导细胞死亡的凋亡细胞二维凝胶图谱中一些差异表达的蛋白质。对半胱天冬酶敏感基序的搜索表明，III型中间丝蛋白（波形蛋白）会发生蛋白水解，以促进凋亡的执行阶段，其方式类似于已得到充分证实的V型（核纤层蛋白）和I型（角蛋白18、19）中间丝蛋白。此外，波形蛋白及其一些衍生多肽据报道对凋亡过程具有特异性，它们对应于泛素化蛋白，因此表明在凋亡过程中蛋白质泛素化在溶解中间丝网络方面存在复杂的相互关系。
