Mechanochemistry of Actin Networks

马里兰大学帕克分校的Garegin A. Papoian获得了化学理论、模型和计算方法项目、计算和数据驱动科学与工程项目（CDS&amp；E）和高级网络基础设施部门的奖励，为生物和人工系统中的“活性物质”的计算建模开发先进的算法和软件。帕波亚研究小组将注意力集中在分子马达上。自然界中常见的物质，如气体、液体和固体，都是由周围热环境产生的随机分子碰撞控制的。然而，在生物和人工系统中，分子马达可能产生定向力，产生所谓的活性物质，具有复杂的化学和物理行为。活性物质的一个突出例子是高等生物细胞内的肌动蛋白细胞骨架。相应的细胞骨架化学和动力学负责细胞运动，形状和机械传感。帕波亚实验室运用他们的计算方法阐明了活性物质的自组织原理，揭示了化学和机械过程之间尚未被很好理解的相互作用。这项研究的软件和概念见解将导致对细胞和人工活性物质系统的机械生物学的更深层次的理解。理解活性物质是现代科学面临的重大挑战之一。真核细胞的细胞骨架是一个重要的活性物质系统，主要由肌动蛋白网络组成，由复杂的信号和调节蛋白网络在空间和时间上控制。由此产生的化学、机械和运输过程之间的耦合产生了紧急集体行为，包括细胞迁移和细胞机械传感。帕波扬博士的实验室开发了先进的算法和软件，用于计算含有肌凝蛋白（myosins）分子马达的基于肌动蛋白的细胞骨架。他们建立在先前由Papoian博士的团队开发的反应扩散算法的基础上，加入了肌动蛋白细胞骨架的创新力学模型。他们的计算大大提高了我们目前对人工重组系统和活细胞中肌动蛋白网络自组装和动力学原理的理解。此外，新开发的计算算法影响了肌动蛋白细胞骨架领域以外的许多研究领域，例如帮助更好地理解和建模活性凝胶。模拟软件将在网上免费分发，也将用于教育和外联活动。

Garegin A. Papoian of the University of Maryland, College Park is supported by an award from the Chemical Theory, Models and Computational Methods program, the Computational and Data-Enabled Science and Engineering program (CDS&E) and the Division of Advanced Cyberinfrastructure to develop advanced algorithms and software for computational modeling of "active matter" in biological and artificial systems. The Papoian research group focuses their attention on molecular motors. Commonly encountered matter in the natural world, such as gases, liquids and solids, are governed by random molecular collisions resulting from the surrounding thermal environment. However, in biological and artificial systems, molecular motors may generate directional forces, producing so-called active matter, with complex chemical and physical behaviors. One prominent example of an active matter is the actin cytoskeleton inside cells of higher organisms. The corresponding cytoskeletal chemistry and dynamics are responsible for cellular motility, shape and mechano-sensing. The Papoian laboratory applies their computational approaches to shed light on the principles of self-organization in active matter, to uncover the not-yet-well-understood interplay between the chemical and mechanical processes. The software and conceptual insights resulting from this research will lead to deeper understanding of the mechano-biology of cells and artificial active matter systems.Understanding active matter is one of the profound challenges of modern science. A prominent active matter system, the cytoskeleton of a eukaryotic cell, largely consists of actin networks, controlled spatially and temporally by an intricate web of signaling and regulatory proteins. The resulting couplings among the chemical, mechanical and transport processes give rise to emergent collective behavior, including cell migration and cellular mechano-sensing. Dr. Papoian's laboratory develops advanced algorithms and software for computational modeling of the actin-based cytoskeletons containing molecular motors, called myosins. They build upon the reaction-diffusion algorithms previously developed by Dr. Papoian's group by adding innovative mechanical models of the actin cytoskeleton. Their calculations significantly advance our current understanding of the principles governing actin network self-assembly and dynamics in both artificially reconstituted systems and living cells. In addition, newly developed computational algorithms impact many research areas beyond the actin cytoskeleton field, such as helping to better understand and model active gels. The simulation software will be freely disseminated on-line and also used in educational and outreach activities.