标题： 玫瑰花结形成作为对称性破缺事件：理论和实验 显示英文标题

标题： Rosette formations as symmetry-breaking events: theory and experiment

摘要： 多细胞玫瑰花型结构在形态发生、伤口愈合和癌症进展等多种情况下被观察到。虽然已经获得了一些分子层面的见解来解释这些由五个或更多细胞围绕一个共同中心形成的集合体的存在，但哪些可调的全局特征有利于或阻碍它们的形成仍然很大程度上未知。 在这里，我们利用Voronoi动力学模型研究了驱动具有不同稳定性和组织程度的玫瑰花型结构出现的因素。我们发现（i）打破系统中的局部空间对称性，即引入诱导曲率的缺陷，允许形成类似玫瑰花型的结构；（ii）其形成概率取决于细胞层的特性。特别是，组织流动性与单个细胞变形性的权衡决定了瞬态玫瑰花型结构的组装，在存在细胞取向相互作用的情况下，这些结构会被强烈稳定。 为了验证我们的模型预测，我们在源自诱导多能干细胞(iPSCs)的玫瑰花型形成神经群体上进行了荧光显微镜实验，发现了显著的一致性。 总体而言，我们的工作可能为统一理解涉及生理条件下玫瑰花型结构出现以及病理条件下异常形成的众多生物物理机制奠定基础。 显示英文摘要

摘要： Multicellular rosettes are observed in different situations such as morphogenesis, wound healing, and cancer progression. While some molecular insights have been gained to explain the presence of these assemblies of five or more cells around a common center, what are the tunable, global features that favors/hinders their formation is still largely unknown. Here, we made use of a Voronoi dynamical model to investigate the ingredients driving the emergence of rosettes characterized by different degree of stability and organization. We found that (i) breaking the local spatial symmetry of the system, i.e., introducing curvature-inducing defects, allows for the formation of rosette-like structures (ii) whose probability of formation depends on the characteristic of the cellular layer. In particular, a trade-off between tissue fluidity and single cell deformability dictates the assembly of transient rosettes, that are strongly stabilized in the presence of cell alignment interactions. To test our model predictions, we performed fluorescence microscopy experiments on rosette-forming neural populations derived from induced pluripotent stem cells (iPSCs), finding significant agreement. Overall, our work may set the stage to gain an unifying understanding of the plethora of biophysical mechanisms involving the occurrence of rosette-like structure both in physiology and their altered formation in pathology.