Phosphorylation of the F-BAR protein Hof1 drives septin ring splitting in budding yeast Auteur(s): Varela Salgado Maritzaida, Adriaans Ingrid, Touati Sandra, Ibanes Sandy, Lai-Kee-Him Joséphine, Ancelin Aurélie, Cipelletti L., Picas Laura, Piatti Simonetta (Article) Publié: Nature Communications, vol. 15 p.3383 (2024) Texte intégral en Openaccess : Ref HAL: hal-04732675_v1 PMID 38649354 DOI: 10.1038/s41467-024-47709-3 Exporter : BibTex | endNote Résumé: A double septin ring accompanies cytokinesis in yeasts and mammalian cells. In budding yeast, reorganisation of the septin collar at the bud neck into a dynamic double ring is essential for actomyosin ring constriction and cytokinesis. Septin reorganisation requires the Mitotic Exit Network (MEN), a kinase cascade essential for cytokinesis. However, the effectors of MEN in this process are unknown. Here we identify the F-BAR protein Hof1 as a critical target of MEN in septin remodelling. Phospho-mimicking HOF1 mutant alleles overcome the inability of MEN mutants to undergo septin reorganisation by decreasing Hof1 binding to septins and facilitating its translocation to the actomyosin ring. Hof1-mediated septin rearrangement requires its F-BAR domain, suggesting that it may involve a local membrane remodelling that leads to septin reorganisation. In vitro Hof1 can induce the formation of intertwined septin bundles, while a phosphomimetic Hof1 protein has impaired septin-bundling activity. Altogether, our data indicate that Hof1 modulates septin architecture in distinct ways depending on its phosphorylation status. |