Figure 1. The influence of GRNs, cellular effectors, and neighboring mechanics on tissue morphogenesis.

Morphological structures are pre-patterned by GRNs (red) that turn on a precise set of effector molecules (green). These effectors control cell behaviors, here altering the shape of cells, together forming the final phenotype. (Left) An example of these processes occurring during ventral furrow formation where a nuclear gradient of the transcription factor Dorsal activates downstream transcription factors, which in turn activate effector molecules. These effector molecules accumulate at the apical membrane, causing the cells to apically constrict, and resulting in tissue invagination. (Right) Depiction of the interaction between gene regulatory networks, cellular effectors, and cell behaviors. While networks activate effectors (A), which drive changes in cell behaviors (B), development can also be influenced by signals and mechanical cues coming from neighboring cells in addition to feedback from different parts of the process (C).