Dave Jui M, Bayless Kayla J
Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas, USA.
Microcirculation. 2014 May;21(4):333-44. doi: 10.1111/micc.12111.
Angiogenesis is a multistep process that requires intricate changes in cell shape to generate new blood vessels. IF are a large family of proteins that play an important structural and functional role in forming and regulating the cytoskeleton. Vimentin, a major type III intermediate filament protein is expressed in endothelial and other mesenchymal cells. The structure of vimentin is conserved in mammals and shows dynamic expression profiles in various cell types and different developmental stages. Although initial studies with vimentin-deficient mice demonstrated a virtually normal phenotype, subsequent studies have revealed several defects in cell attachment, migration, signaling, neurite extension, and vascularization. Regulation of vimentin is highly complex and is driven by posttranslational modifications such as phosphorylation and cleavage by intracellular proteases. This review discusses various novel functions which are now known to be mediated by vimentin, summarizing structure, regulation and roles of vimentin in cell adhesion, migration, angiogenesis, neurite extension, and cancer. We specifically highlight a pathway involving growth factor-mediated calpain activation, vimentin cleavage, and MT1-MMP membrane translocation that is required for endothelial cell invasion in 3D environments. This pathway may also regulate the analogous processes of neurite extension and tumor cell invasion.
血管生成是一个多步骤过程,需要细胞形态发生复杂变化以生成新血管。中间丝蛋白是一个大家族的蛋白质,在形成和调节细胞骨架中发挥重要的结构和功能作用。波形蛋白是一种主要的III型中间丝蛋白,在内皮细胞和其他间充质细胞中表达。波形蛋白的结构在哺乳动物中是保守的,并且在各种细胞类型和不同发育阶段表现出动态表达谱。尽管最初对波形蛋白缺陷小鼠的研究显示出几乎正常的表型,但随后的研究揭示了细胞附着、迁移、信号传导、神经突延伸和血管形成方面的一些缺陷。波形蛋白的调节高度复杂,由翻译后修饰如磷酸化和细胞内蛋白酶的切割驱动。本综述讨论了目前已知由波形蛋白介导的各种新功能,总结了波形蛋白在细胞粘附、迁移、血管生成、神经突延伸和癌症中的结构、调节和作用。我们特别强调了一条涉及生长因子介导的钙蛋白酶激活、波形蛋白切割和MT1-MMP膜易位的途径,这是内皮细胞在三维环境中侵袭所必需的。该途径也可能调节神经突延伸和肿瘤细胞侵袭的类似过程。