Theoretical modeling on mechanochemical feedbacks of cellular processes

1.膜贩子： 在这个项目中，我们研究了BAR和F-BAR结构域蛋白在酵母内吞作用中的功能作用。我们的研究表明，强健的肌动蛋白聚合、F-bar和bar结构域蛋白以及突触素之间的合作对膜断裂是重要的。时空和功能信息以及我们的理论模型表明内吞作用的图景如下：F-bar蛋白稳定内吞部位，而肌动蛋白组装和bar蛋白协同内陷和断裂。这篇论文目前正在审查中，准备出版。 2.动粒运动性： 基于动粒环沿微管的相邻距离直方图，建立了一个判别环是否能扩散的统计模型。我们的研究表明，动粒环一定是高度扩散的。这篇论文目前正在准备出版。 3.胞质分裂过程中的不对称沟内移： 我们构建了一个关于肌动球蛋白环在胞质分裂过程中收缩的最小模型。我们的模型认为，沟槽位置的局部几何形状，如膜的高斯曲率，可以促进肌动球蛋白细丝的排列过程，进而控制局部收缩的效率。随着局部肌动球蛋白微丝收缩的越多，局部高斯曲率越大。我们发现，这一机制可以定量地解释肌动球蛋白收缩的所有三种模式，这取决于局部膜曲率和肌动球蛋白收缩之间正反馈的耦合强度。更重要的是，我们的实验测试证实了我们模型独有的几个预测，表明了曲率介导的细胞动力肌球蛋白收缩正反馈的紧急机制。此外，该模型还表明，不对称沟槽内移在能量上更有效，从而表明不对称在细胞动态环收缩中具有真正的功能作用。这是同类车型中的第一款。这篇论文目前正在准备出版。

1. Membrane Trafficking: In this project, we investigated the functional role of the BAR and F-BAR domain proteins in yeast endocytosis. Our research showed that cooperation between robust actin polymerization, and F-BAR and BAR domain proteins, and synaptojanin, is important for membrane scission. Spatio-temporal and functional information together with our theoretical modeling suggest the following picture of endocytosis: F-BAR proteins stabilize the endocytic site, while actin assembly and BAR proteins cooperate for invagination and scission. This paper is currently under review for publication. 2. Kinetochore motility: Based on the histogram of the neighboring distance between kinetochore ring along microtubule, I contructed a statistical model to differentiate whether the rings can diffuse or not. Our research shows that kinetochore ring must be highly diffusive. The paper is currently in preparation for publication. 3. Asymmetric Furrow ingression during cytokinesis: We construct a minimal model on the contractility of actomyosin ring during cytokinesis. Our model proposes that the local geometry of the furrow site, such as the Gaussian curvature of the membrane, could promote the alignment process of actomyosin filament, which in turn governs the efficiency of the local contractility. As the more the local actomyosin filament contracts, the larger the local Gaussian curvature would become. We show that this mechanism can quantitatively account for all the three modes of actomyosin contractility, depending on the coupling strength of the positive feedback between the local membrane curvature and actomyosin contractility. More importantly, our experimental testing corroborates several predictions unique to our model, suggesting an emergent mechanism of curvature-mediated positive feedback for cytokinetic actomyosin contractility. Furthermore, the model demonstrate that asymmetric furrow ingression is energetically more efficient, thereby suggesting a real functional role of the asymmetry in cytokinetic ring contraction. This model is the first of its kinds. This paper is currently in preparation for publication.