Molecular basis of functional exchangeability between ezrin and other actin-membrane associated proteins during cytokinesis

• Published in: Experimental cell research 2021-06, Vol.403 (2), p.112600-112600, Article 112600
• Main Authors: Yang, Guang, Hiruma, Shota, Kitamura, Akira, Kinjo, Masataka, Mishra, Mithilesh, Uehara, Ryota
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; ACTIN; Blebbing; CELL PROLIFERATION; Cytokinesis; ERM; LYMPHOKINES; MICROTUBULES; MUTANTS; MYOSIN
• ISSN: 0014-4827; 1090-2422
• DOI: 10.1016/j.yexcr.2021.112600

The mechanism that mediates the interaction between the contractile ring and the plasma membrane during cytokinesis remains elusive. We previously found that ERM (Ezrin/Radixin/Moesin) proteins, which usually mediate cellular pole contraction, become over-accumulated at the cell equator and support furrow ingression upon the loss of other actin-membrane associated proteins, anillin and supervillin. In this study, we addressed the molecular basis of the exchangeability between ezrin and other actin-membrane associated proteins in mediating cortical contraction during cytokinesis. We found that depletion of anillin and supervillin caused over-accumulation of the membrane-associated FERM domain and actin-binding C-terminal domain (C-term) of ezrin at the cleavage furrow, respectively. This finding suggests that ezrin differentially shares its binding sites with these proteins on the actin cytoskeleton or inner membrane surface. Using chimeric mutants, we found that ezrin C-term, but not the FERM domain, can substitute for the corresponding anillin domains in cytokinesis and cell proliferation. On the other hand, either the membrane-associated or the actin/myosin-binding domains of anillin could not substitute for the corresponding ezrin domains in controlling cortical blebbing at the cell poles. Our results highlight specific designs of actin- or membrane-associated moieties of different actin-membrane associated proteins with limited exchangeability, which enables them to support diverse cortical activities on the shared actin-membrane interface during cytokinesis. •Anillin or supervillin depletion affects localization of different domains of ezrin.•Actin binding domains are compatible between ezrin and anillin for furrow ingression.•All ezrin and anillin domains are incompatible for polar cortical control.