上皮-间质转化(epithelial to mesenchymal transition,EMT)是胚胎发育、伤口愈合、癌症发展等生理、病理过程中的关键步骤,使细胞从紧密黏附在一起的上皮状态转变为分散排布的间质状态.该文提出了一个基质刚度和生长因子协同驱动EMT的...上皮-间质转化(epithelial to mesenchymal transition,EMT)是胚胎发育、伤口愈合、癌症发展等生理、病理过程中的关键步骤,使细胞从紧密黏附在一起的上皮状态转变为分散排布的间质状态.该文提出了一个基质刚度和生长因子协同驱动EMT的核心调控回路模型,发现在EMT过程中,基质刚度和生长因子通过协同调控EMT激活转录因子(EMT-activating transcript factors,EMT-TFs)来改变细胞间力学黏附分子E/N-钙黏素的表达,从而影响EMT的进程与可逆性.该模型揭示了力学和化学因素的协同作用对EMT过程中细胞间力学黏附的影响机制,为研究癌症等疾病的发生、发展机制和防治策略奠定了理论基础.展开更多
Cells are capable of sensing and responding to the extracellular mechanical microenvironment via the actin skeleton.In vivo,tissues are frequently subject to mechanical forces,such as the rapid and significant shear f...Cells are capable of sensing and responding to the extracellular mechanical microenvironment via the actin skeleton.In vivo,tissues are frequently subject to mechanical forces,such as the rapid and significant shear flow encountered by vascular endothelial cells.However,the investigations about the transient response of intracellular actin networks under these intense external mechanical forces,their intrinsic mechanisms,and potential implications are very limited.Here,we observe that when cells are subject to the shear flow,an actin ring structure could be rapidly assembled at the periphery of the nucleus.To gain insights into the mechanism underlying this perinuclear actin ring assembly,we develop a computational model of actin dynamics.We demonstrate that this perinuclear actin ring assembly is triggered by the depolymerization of cortical actin,Arp2/3-dependent actin filament polymerization,and myosin-mediated actin network contraction.Furthermore,we discover that the compressive stress generated by the perinuclear actin ring could lead to a reduction in the nuclear spreading area,an increase in the nuclear height,and a decrease in the nuclear volume.The present model thus explains the mechanism of the perinuclear actin ring assembly under external mechanical forces and suggests that the spontaneous contraction of this actin structure can significantly impact nuclear morphology.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 12025207 and 11872357)the Fundamental Research Funds for the Central Universities。
文摘Cells are capable of sensing and responding to the extracellular mechanical microenvironment via the actin skeleton.In vivo,tissues are frequently subject to mechanical forces,such as the rapid and significant shear flow encountered by vascular endothelial cells.However,the investigations about the transient response of intracellular actin networks under these intense external mechanical forces,their intrinsic mechanisms,and potential implications are very limited.Here,we observe that when cells are subject to the shear flow,an actin ring structure could be rapidly assembled at the periphery of the nucleus.To gain insights into the mechanism underlying this perinuclear actin ring assembly,we develop a computational model of actin dynamics.We demonstrate that this perinuclear actin ring assembly is triggered by the depolymerization of cortical actin,Arp2/3-dependent actin filament polymerization,and myosin-mediated actin network contraction.Furthermore,we discover that the compressive stress generated by the perinuclear actin ring could lead to a reduction in the nuclear spreading area,an increase in the nuclear height,and a decrease in the nuclear volume.The present model thus explains the mechanism of the perinuclear actin ring assembly under external mechanical forces and suggests that the spontaneous contraction of this actin structure can significantly impact nuclear morphology.
