PGC-derived migrasomes couple PGC proliferation with migration

Area of Science:

• Developmental Biology
• Cell Biology
• Molecular Biology

Background:

• Coordinated cell migration and proliferation are crucial for embryogenesis and tissue maintenance.
• The classical gradient signaling model cannot fully explain sustained mitogenic signaling in migrating cells.

Purpose of the Study:

• To investigate the mechanism by which migrating primordial germ cells (PGCs) in zebrafish maintain proliferation.
• To explore the role of migrasomes in coupling cell migration and proliferation during germline development.

Main Methods:

• Utilized zebrafish as a model organism.
• Investigated the biogenesis and function of migrasomes in PGCs.
• Analyzed the role of tspan7 in migrasome formation and GDF3 delivery.
• Examined GDF3-mediated activation of the TGF-β receptor (acvr1ba) pathway.

Main Results:

• PGCs generate migrasomes, which are vesicular organelles formed at retraction fibers.
• Migrasomes deliver the growth factor GDF3 to neighboring PGCs via contact-dependent interactions.
• GDF3 activates the acvr1ba receptor, promoting spatiotemporally restricted proliferation.
• This homocrine signaling mechanism allows migrating PGCs to autonomously sustain proliferation.

Conclusions:

• Migrasomes act as a novel signaling platform, bridging cell migration and proliferation in zebrafish PGCs.
• This migrasome-mediated homocrine signaling circumvents signal dilution in the embryonic environment.
• The findings reveal a new mechanism for collective cell behavior with implications for development and disease.