Bidirectional redistribution of actomyosin drives epithelial invagination in ascidian siphon tube morphogenesis.

Bidirectional redistribution of actomyosin drives epithelial invagination during ascidian siphon tube morphogenesis.

• Why it matters: Understanding the mechanical mechanisms of tissue morphogenesis is crucial for insights into organ development, yet the precise actomyosin dynamics involved remain unclear.
• What they did: The study used genetic mutants, optogenetics, and vertex model simulations to analyze actomyosin reorganization between apical and lateral membranes during two invagination stages in Ciona.
• The result: Findings show actomyosin first redistributes from lateral to apical regions to initiate invagination, then back laterally to accelerate it, revealing a bidirectional reorganization as a key driver of epithelial invagination.