Nicotine affects intestinal stem cells rather than Paneth cells, resulting in the increased stemness and tumorigenicity of intestinal stem cells.

Active and passive contributions to cell shape change and rearrangements can be distinguished from observed cell geometry, revealing the self-organization mechanisms underlying internally-driven epithelial convergent extension.

A noisy cell-intrinsic timer provides positional information for the segmentation clock, modulated by extrinsic factors such as FGF.