Active junctional fluctuation-driven ordering in 3D cellular aggregates

Order-disorder transitions in tissues are frequently observed during development and disease progression. However, the mechanics of such transitions in bulk three-dimensional (3D) tissues remain poorly understood. We investigate 3D cellular aggregates using the vertex model to address this gap. We employ active fluctuating tension at cellular junctions of these aggregates to explore their energy landscapes. Our results reveal that the cellular aggregates achieve efficient ordering at an intermediate amplitude of fluctuating tension. This ordered state is further supported by a non-monotonic response in the structure factor and pair correlation functions as the tension amplitude varies. Additional structural analyses, including edge length and shape factor distributions, indicate maximal order at intermediate amplitude levels. Furthermore, the dynamic behavior of the aggregates, characterized by the effective diffusivity of cells, reveals a transition from solid-like to fluid-like behavior, depending on the amplitude and persistence time of the fluctuating tension, particularly near the values where maximal order is observed.