Quantitative system-level analysis of a pattern-forming gene regulatory network in a non-model organism shows that dynamic changes in gene expression evolve through quantitative system drift.
Dissection of a cis-regulatory element (CRM) in its native chromosomal context using CRISPR/Cas9 editing and novel 'Active Genetics' reveals new features of CRM function and insights into how such regulatory elements change during evolution.
Functional recapitulation of a likely evolutionary gain in gene expression shows that two genes are sufficient to switch mesoderm cell internalization from stochastic cell ingression to coordinated epithelial invagination.