ESCRT-III Assembly and Cytokinetic Abscission Are Induced by Tension Release in the Intercellular Bridge

Abstract

The last step of cell division, cytokinesis, produces two daughter cells that remain connected by an intercellular bridge. This state often represents the longest stage of the division process. Severing the bridge (abscission) requires a well-described series of molecular events, but the trigger for abscission remains unknown. We found that pulling forces exerted by daughter cells on the intercellular bridge appear to regulate abscission. Counterintuitively, these forces prolonged connection, whereas a release of tension induced abscission. Tension release triggered the assembly of ESCRT-III (endosomal sorting complex required for transport-III), which was followed by membrane fission. This mechanism may allow daughter cells to remain connected until they have settled in their final locations, a process potentially important for tissue organization and morphogenesis.

Cytokinetic Abscission: Phosphoinositides and ESCRTs Direct the Final Cut

“…Among the four multi-subunit protein complexes (ESCRT 0-I-II-III), extensive studies reported the fundamental role of ESCRT-III in abscission (Capalbo et al, 2016;Carlton et al, 2012;Carlton and Martin-Serrano, 2007;Eikenes et al, 2015;Lafaurie-Janvore et al, 2013;Morita et al, 2007). ESCRT-III becomes enriched at the midbody, an organelle at the intercellular bridge, which acts as a platform for the recruitment and organisation of various proteins involved in both the control and execution of the abscission process.…”

Mécanique et division cellulaire

“…Dans le cadre d'un travail récemment publié dans Science [10], nous avons souhaité étudier les facteurs environnementaux qui pourraient retarder ou induire l'abscission des cellules. Nous nous sommes intéressés en particulier au rôle des forces de traction exercées irréversible puisqu'aucun retour en arrière n'est possible une fois le pont coupé.…”

Cytokinesis in Metazoa and Fungi

“…Some variability might be due to the variable rate of daughter cell spreading that exerts tension on the intercellular bridge. Counterintuitively, increased tension on the bridge induces a delay in abscission (Lafaurie-Janvore et al 2013 Figure 4. Abscission in metazoa.…”