Richardson J, Gauert A, Briones L, Escudero L, Zainalabdeen A, Gorostiza E, Kabla A, Assar R, Härtel S & C Linker
Cell Reports, Cell Reports 15(9), 1-13

Collective cell migration is fundamental for life and a hallmark of cancer. Neural crest cells (NCs) are a migratory population sharing many characteristics with metastatic cells. NCs migrate collectively, but the mechanisms governing this process remain controversial. Xenopus experiments indicate that cranial NCs (CNCs) are a homogeneous population relying on cell-cell interactions for directional migration, while experiments from chick embryos suggest they are heterogeneous with leader cells instructing directionality. Our data in chick and zebrafish embryos shows that CNCs are a homogeneous group that does not required leader cells for directional migration. In contrast, laser ablation of trunk NCs (TNCs) show these are a heterogeneous population: leader cells direct movement and cell-cell contacts are required for migration. Moreover, migratory identity is acquired before the initiation of migration and remains fixed thereafter. Thus, two distinct mechanisms establish the directionality of CNCs and TNCs. This implies the existence of multiple and perhaps mutually exclusive molecular mechanisms for collective cell migration.