Search

Integrin- and cadherin-mediated adhesion is central for cell and tissue morphogenesis, allowing cells and tissues to change shape without loosing integrity. Studies predominantly in cell culture showed that mechanosensation through adhesion structures is achieved by force-mediated modulation of their molecular composition. The specific molecular composition of adhesion sites in turn determines their signalling activity and dynamic reorganization. Here, we will review how adhesion sites respond to mecanical stimuli, and how spatially and temporally regulated signalling from different adhesion sites controls cell migration and tissue morphogenesis.

The migration of single cells and epithelial sheets is of great importance for gastrulation and organ formation in developing embryos and, if misregulated, can have dire consequences e.g. during cancer metastasis. A keystone of cell migration is the regulation of adhesive contacts, which are dynamically assembled and disassembled via endocytosis. Here, we discuss some of the basic concepts about the function of endocytic trafficking during cell migration: transport of integrins from the cell rear to the leading edge in fibroblasts; confinement of signalling to the front of single cells by endocytic transport of growth factors; regulation of movement coherence in multicellular sheets by cadherin turnover; and shaping of extracellular chemokine gradients. Taken together, endocytosis enables migrating cells and tissues to dynamically modulate their adhesion and signalling, allowing them to efficiently migrate through their extracellular environment.

During zebrafish gastrulation, the interplay between patterning events and morphogenesis creates an embryo out of a seemingly unstructured blastula stage embryo, an embryo with distinct polarities along its anterior–posterior, dorsoventral and left–right axes at the end of gastrulation. Keywords: morphogenesis; patterning

The spatiotemporal control of cell divisions is a key factor in epithelial morphogenesis and patterning. Mao et al (2013) now describe how differential rates of proliferation within the Drosophila wing disc epithelium give rise to anisotropic tissue tension in peripheral/proximal regions of the disc. Such global tissue tension anisotropy in turn determines the orientation of cell divisions by controlling epithelial cell elongation. Oriented cell divisions play important roles in the establishment of the animal body plan by both influencing tissue morphogenesis and generating cellular diversity. Generally, the direction of the cell division plane is determined by the orientation of the mitotic spindle prior to cytokinesis. The observation that the mitotic spindle in most animal cell types aligns with the cell's longest axis has led to the formulation of the ‘long‐axis‐rule’, postulating that cell shape anisotropy is the main determinant of spindle orientation (Minc et al , 2011). However, cell shape anisotropy is unlikely to be the only determinant since many cell types round up during mitosis, thereby losing their shape anisotropy and others do not follow the long‐axis‐rule at all. In such …