Does cell shape predict whether a tissue flows or holds? · revision history
Revision 2
Accepted · core change · record
Changes against revision 1:
- Title
- Does cell shape predict whether a tissue flows or holds?
- Plain
- Computer models of tightly packed cells predict that a tissue switches from solid-like to fluid-like once cells become elongated beyond a critical shape. Experiments disagree on whether this shape rule works in real tissues.
- Precise · changed · core
- Revision 1: The 2D vertex model with energy $E = \operatorname{sum}_i [K_A (A_i - A_0)^2 + K_P (P_i - P_0)^2]$ ($A_i, P_i$ = cell area and perimeter) has a rigidity transition at target shape index $p_0 = P_0/\sqrt{A_0} \sim 3.81$. Determine whether the observed shape index $q = \langle P/\sqrt{A}\rangle$ classifies fluid versus solid epithelia in vivo across tissues and species, or whether fluctuations, division and active tension remodeling set fluidity independently of q.
- Revision 2: The 2D vertex model with energy $E = \sum_i [K_A (A_i - A_0)^2 + K_P (P_i - P_0)^2]$ ($A_i, P_i$ = cell area and perimeter) has a rigidity transition at target shape index $p_0 = P_0/\sqrt{A_0} \sim 3.81$. Determine whether the observed shape index $q = \langle P/\sqrt{A}\rangle$ classifies fluid versus solid epithelia in vivo across tissues and species, or whether fluctuations, division and active tension remodeling set fluidity independently of q.
- Settled by
- Simultaneous in vivo measurement of q and of tissue rheology (cell rearrangement rate, stress relaxation) across several tissues and perturbations.
- Kind
- well-posed
- Answer type
- yes-no
- References
- (empty)
- Literature status
- contested
- Status note
- Support from airway epithelia (2015) contrasts with 2026 reports of shape-independent fluidity in epithelial monolayers (arXiv 2603.05548).
- Posed since
- 2015
Decisions
- Accept · 2026-10-15 · record