Details

Autor(en) / Beteiligte

• Samarage, Chaminda R.
• White, Melanie D.
• Álvarez, Yanina D.
• Fierro-González, Juan Carlos
• Henon, Yann
• Jesudason, Edwin C.
• Bissiere, Stephanie
• Fouras, Andreas
• Plachta, Nicolas

Titel

Cortical Tension Allocates the First Inner Cells of the Mammalian Embryo

Ist Teil von

• Developmental cell, 2015-08, Vol.34 (4), p.435-447

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2015

Quelle

MEDLINE

Beschreibungen/Notizen

• Every cell in our body originates from the pluripotent inner mass of the embryo, yet it is unknown how biomechanical forces allocate inner cells in vivo. Here we discover subcellular heterogeneities in tensile forces, generated by actomyosin cortical networks, which drive apical constriction to position the first inner cells of living mouse embryos. Myosin II accumulates specifically around constricting cells, and its disruption dysregulates constriction and cell fate. Laser ablations of actomyosin networks reveal that constricting cells have higher cortical tension, generate tension anisotropies and morphological changes in adjacent regions of neighboring cells, and require their neighbors to coordinate their own changes in shape. Thus, tensile forces determine the first spatial segregation of cells during mammalian development. We propose that, unlike more cohesive tissues, the early embryo dissipates tensile forces required by constricting cells via their neighbors, thereby allowing confined cell repositioning without jeopardizing global architecture. [Display omitted] •Apical constriction allocates the first inner cells of the mouse embryo•Myosin II accumulates around constricting cells and is needed for their allocation•Subcellular heterogeneities in tensile forces determine inner cell allocation•Neighboring cells dissipate tensile forces required by constricting cells Samarage et al. show how mechanical forces form the early mouse embryo. They show that anisotropies in cortical tension—a force generated by contractility of the actomyosin cell cortex—drive the first spatial segregation of cells into the inner regions of the embryo during mammalian development.