The EMBO Journal - 2023 - Bonello - Phase separation of Hippo signalling complexes (1).pdf (11.25 MB)
Phase separation of Hippo signalling complexes.
journal contributionposted on 2023-03-15, 10:57 authored by Teresa T Bonello, Danfeng Cai, Georgina C Fletcher, Kyler Wiengartner, Victoria Pengilly, Kimberly S Lange, Zhe Liu, Jennifer Lippincott-Schwartz, Jennifer M Kavran, Barry J Thompson
The Hippo pathway was originally discovered to control tissue growth in Drosophila and includes the Hippo kinase (Hpo; MST1/2 in mammals), scaffold protein Salvador (Sav; SAV1 in mammals) and the Warts kinase (Wts; LATS1/2 in mammals). The Hpo kinase is activated by binding to Crumbs-Expanded (Crb-Ex) and/or Merlin-Kibra (Mer-Kib) proteins at the apical domain of epithelial cells. Here we show that activation of Hpo also involves the formation of supramolecular complexes with properties of a biomolecular condensate, including concentration dependence and sensitivity to starvation, macromolecular crowding, or 1,6-hexanediol treatment. Overexpressing Ex or Kib induces formation of micron-scale Hpo condensates in the cytoplasm, rather than at the apical membrane. Several Hippo pathway components contain unstructured low-complexity domains and purified Hpo-Sav complexes undergo phase separation in vitro. Formation of Hpo condensates is conserved in human cells. We propose that apical Hpo kinase activation occurs in phase separated "signalosomes" induced by clustering of upstream pathway components.