Abstract:
The cytoskeleton of the cell is constantly exposed to physical forces that regulate cellular functions. Selected members of the LIM (Lin-11, Isl-1, and Mec-3) domain-containing protein family accumulate along force-bearing actin fibers, with evidence supporting that the LIM domain is solely responsible for this force-induced interaction. However, LIM domain\'s force-induced interactions are not limited to actin. LIMK1 and LMO1, both containing only two tandem LIM domains, are recruited to force-bearing keratin fibers in epithelial cells. This unique recruitment is mediated by their LIM domains and regulated by the sequences outside the LIM domains. Based on in vitro reconstitution of this interaction, LIMK1 and LMO1 directly interact with stretched keratin 8/18 fibers. These results show that LIM domain\'s mechano-sensing abilities extend to the keratin cytoskeleton, highlighting the diverse role of LIM proteins in force-regulated signaling.
摘要:
细胞的细胞骨架不断暴露于调节细胞功能的物理力。LIM(Lin-11,Isl-1和Mec-3)结构域蛋白质家族的选定成员沿受力肌动蛋白纤维积累,有证据支持LIM域完全负责这种力诱导的相互作用。然而,LIM域的力诱导相互作用不限于肌动蛋白。LIMK1和LMO1,都只包含两个串联的LIM域,被募集到上皮细胞中的强力角蛋白纤维。这种独特的募集由它们的LIM结构域介导并由LIM结构域外的序列调节。基于这种相互作用的体外重建,LIMK1和LMO1直接与拉伸的角蛋白8/18纤维相互作用。这些结果表明,LIM结构域的机械感应能力扩展到角蛋白细胞骨架,强调LIM蛋白在力调节信号中的不同作用。