Self-organized intracellular twisters

Area of Science:

• Cellular biology
• Biophysics
• Developmental biology

Background:

• Complex systems, from cities to cells, rely on coordinated mass, energy, and information flow.
• Large oocytes and embryos utilize rapid cytoplasmic fluid flows for reorganization.
• In Drosophila oocytes, cortical microtubules and molecular motors are hypothesized to drive cytoplasmic streaming.

Approach:

• Combined theoretical modeling, computational simulations, and advanced imaging techniques.
• Developed a fast, accurate, and scalable numerical method for fluid-structure interactions.
• Investigated the behavior of thousands of flexible fibers representing cytoskeletal components.

Key Points:

• Demonstrated the spontaneous emergence and evolution of robust, cell-spanning vortices (twisters) in simulated Drosophila oocytes.
• Characterized these vortices as primarily rigid body rotation with secondary toroidal components.
• Highlighted the role of hydrodynamic interactions between cortically anchored microtubules and molecular motors.

Conclusions:

• Cytoplasmic streaming in Drosophila oocytes robustly arises from microtubule-cargo motor interactions.
• These emergent vortices are crucial for rapid mixing and transport of ooplasmic components.
• The findings provide insights into fundamental principles of self-organization in biological fluid dynamics.