Figure 2.

Mechanochemical fate patterning. (a) Notch-dependent fate determination followed by cellular rearrangements leads to precise mosaic arrangements of sensory cells (green) and supporting cells (gray) in mammalian mechanosensory epithelia [33••, 34]. (b) Mechanically induced cell–cell contact changes control Notch-dependent fate decisions in zebrafish heart development. The crowding-induced delamination of cells from the initially monolayered myocardial epithelium enables Notch-dependent lateral inhibition of delamination and trabecular fate in adjacent cells [24••]. (c) Notch-dependent cell–cell contact changes control distinct instances of signaling in zebrafish mechanosensory organs. Notch signaling specifies a sensory progenitor cell (green) among supporting cells (gray). This cell divides into two daughter cells that engage in a second instance of signaling to specify opposite polarity fates (green and gray), triggering oppositely oriented cell movements that terminate the signaling interactions by physically separating the cells [23••]. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)