Pulses of RhoA Signaling Stimulate Actin Polymerization and Flow in Protrusions to Drive Collective Cell Migration

Area of Science:

• Cell Biology
• Developmental Biology
• Biophysics

Background:

• Collective cell migration is crucial for tissue development, wound repair, and disease progression like metastasis.
• Individual cell motility is understood to involve Rho GTPase signaling and the actin network.
• It remains unclear if collective cell migration utilizes similar molecular machinery.

Approach:

• The study utilized the zebrafish posterior lateral line primordium as a model system for collective cell migration.
• Investigated the roles of RhoA and myosin II activity during this process.
• Analyzed the spatiotemporal dynamics of signaling and their impact on cellular structures and the basement membrane.

Key Points:

• Active RhoA and myosin II were found to cluster on the basal side of migrating primordium cells.
• Their activity was observed to pulse, driven by positive and negative feedback loops.
• These pulses drive actin polymerization, actin flow, and protrusion dynamics, deforming the underlying basement membrane.

Conclusions:

• RhoA-mediated actin flow on the basal side acts as the primary motor for collective cell migration in this model.
• This mechanism provides a framework for understanding collective cell motility in various biological contexts.
• Highlights the importance of RhoA signaling and cytoskeletal dynamics in coordinating cell movement within a collective.