Maninova Miloslava, Caslavsky Josef, Vomastek Tomas
Institute of Microbiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 00, Prague, Czech Republic.
Protoplasma. 2017 May;254(3):1207-1218. doi: 10.1007/s00709-017-1077-0. Epub 2017 Jan 18.
Stress fibers are actin bundles encompassing actin filaments, actin-crosslinking, and actin-associated proteins that represent the major contractile system in the cell. Different types of stress fibers assemble in adherent cells, and they are central to diverse cellular processes including establishment of the cell shape, morphogenesis, cell polarization, and migration. Stress fibers display specific cellular organization and localization, with ventral fibers present at the basal side, and dorsal fibers and transverse actin arcs rising at the cell front from the ventral to the dorsal side and toward the nucleus. Perinuclear actin cap fibers are a specific subtype of stress fibers that rise from the leading edge above the nucleus and terminate at the cell rear forming a dome-like structure. Perinuclear actin cap fibers are fixed at three points: both ends are anchored in focal adhesions, while the central part is physically attached to the nucleus and nuclear lamina through the linker of nucleoskeleton and cytoskeleton (LINC) complex. Here, we discuss recent work that provides new insights into the mechanism of assembly and the function of these actin stress fibers that directly link extracellular matrix and focal adhesions with the nuclear envelope.
应力纤维是包含肌动蛋白丝、肌动蛋白交联蛋白和肌动蛋白相关蛋白的肌动蛋白束，是细胞中的主要收缩系统。不同类型的应力纤维在贴壁细胞中组装，它们对于包括细胞形状的建立、形态发生、细胞极化和迁移在内的多种细胞过程至关重要。应力纤维呈现出特定的细胞组织和定位，腹侧纤维位于基底侧，背侧纤维和横向肌动蛋白弧从细胞前端的腹侧上升至背侧并朝向细胞核。核周肌动蛋白帽纤维是应力纤维的一种特定亚型，它从细胞核上方的前缘升起并在细胞后部终止，形成穹顶状结构。核周肌动蛋白帽纤维在三个点固定：两端锚定在粘着斑中，而中央部分通过核骨架与细胞骨架（LINC）复合体物理连接到细胞核和核纤层。在这里，我们讨论了最近的研究工作，这些工作为这些直接将细胞外基质和粘着斑与核膜连接起来的肌动蛋白应力纤维的组装机制和功能提供了新的见解。
