Cytoplasmic stirring by active carpets

• 成果类型: Article
• 署名作者: Chakrabarti, Brato; Rachh, Manas; Shvartsman, Stanislav Y.; Shelley, Michael J.
• 署名单位: Simons Foundation; Flatiron Institute; Tata Institute of Fundamental Research (TIFR); International Centre for Theoretical Sciences, Bengaluru; Simons Foundation; Flatiron Institute; Princeton University; Princeton University; New York University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12573
• DOI: 10.1073/pnas.2405114121
• 发表日期: 2024-07-23
• 关键词: flow; alignment; fluid; cells

摘要

Large cells often rely on cytoplasmic flows for intracellular transport, maintaining homeostasis, and positioning cellular components. Understanding the mechanisms of these flows is essential for gaining insights into cell function, developmental processes, and evolutionary adaptability. Here, we focus on a class of self-organized cytoplasmic stirring mechanisms that result from fluid-structure interactions between cytoskeletal elements at the cell cortex. Drawing inspiration from streaming flows in late-stage fruit fly oocytes, we propose an analytically tractable active carpet theory. This model deciphers the origins and three-dimensional spatiotemporal organization of such flows. Through a combination of simulations and weakly nonlinear theory, we establish the pathway of the streaming flow to its global attractor: a cell-spanning vortical twister. Our study reveals the inherent symmetries of this emergent flow, its low-dimensional structure, and illustrates how complex fluid-structure interaction aligns with classical solutions in Stokes flow. This framework can be easily adapted to elucidate a broad spectrum of self-organized, cortex-driven intracellular flows.