Reciprocal coupling between EMT and BMP morphogen signalling drives collective cell invasion.

Reciprocal coupling between EMT initiation and BMP signalling mediated by SNAI2 and SMAD1 drives collective cell invasion in chick tissues.

• Why it matters: Understanding how cell fate specification and invasion are coordinated is crucial for insights into developmental processes and cancer metastasis. The traditional view sees morphogen-driven cell fates and EMT as a linear cascade, but the mechanisms linking these processes remain unclear.
• What they did: The study used ex vivo chick tissue explants, single-cell RNA sequencing, and CRISPR-Cas9 experiments to investigate the relationship between EMT and BMP signalling, focusing on SNAI2 and SMAD1 expression and function.
• The result: Findings show that SNAI2 is required for SMAD1 expression and BMP signalling, which regulates cell fate proportions and migration dynamics, suggesting a mechanism for synchronizing cell fate and invasion during axis elongation.