Discovery of the migrasome, an organelle mediating release of cytoplasmic contents during cell migration

TLDR

Cells communicate by secreting proteins and vesicles, and migrating cells leave retraction fibers behind them. The study aims to discover a migration‑dependent release mechanism and the vesicular structures that mediate it. The authors describe migracytosis, a migration‑dependent release of cellular contents mediated by migrasomes. They find that migrasomes form on retraction fibers, encapsulate cytosolic contents, and are released into the extracellular space or taken up by neighboring cells, establishing migracytosis.

Abstract

Cells communicate with each other through secreting and releasing proteins and vesicles. Many cells can migrate. In this study, we report the discovery of migracytosis, a cell migration-dependent mechanism for releasing cellular contents, and migrasomes, the vesicular structures that mediate migracytosis. As migrating cells move, they leave long tubular strands, called retraction fibers, behind them. Large vesicles, which contain numerous smaller vesicles, grow on the tips and intersections of retraction fibers. These fibers, which connect the vesicles with the main cell body, eventually break, and the vesicles are released into the extracellular space or directly taken up by surrounding cells. Since the formation of these vesicles is migration-dependent, we named them "migrasomes". We also found that cytosolic contents can be transported into migrasomes and released from the cell through migrasomes. We named this migration-dependent release mechanism "migracytosis".