Novel mechanisms for cellular centering and symmetry breaking involving persistent contractile actomyosin flows and their hydrodynamic interactions with the fluid cytosol are presented and studied using a minimal, reconstituted system.
Spatially coordinated apical constriction occurs during Drosophila salivary gland invagination, but the salivary gland can form fully internalized and elongated tubes even when this process is completely blocked.
Combining quantitative biological experiment and physical description of actomyosin cortex reveals a contractile instability in the cortex of C. elegans embryo, and its biochemical control in order to robustly drive morphogenetic events.
By driving the localized contraction of subcellular muscle regions, a single motor neuron reverses the flow of material in the Caenorhabditis elegans pharynx, a neuromuscular pump, converting feeding into spitting.
Positive feedback between contractile ring myosin and compression-driven cortical flow can explain the exponential accumulation of contractile ring components and constriction rate acceleration that ensures timely cell separation during cytokinesis.
Elastic forces generated by the giant protein titin define both passive and active tension of skeletal muscle fibers and protect the sarcomeric myosin filaments from severe disruption during contraction.
High-resolution live imaging analysis shows a constriction mechanism that drives zebrafish optic cup morphogenesis and highlights the role of the extracellular matrix in transmitting tensions beyond the cellular level.