Login / Signup

An ancient Sec10-formin fusion provides insights into actin-mediated regulation of exocytosis.

Peter A C van GisbergenShu-Zon WuMingqin ChangKelli A PattavinaMadelaine E BartlettMagdalena Bezanilla
Published in: The Journal of cell biology (2018)
Exocytosis, facilitated by the exocyst, is fundamentally important for remodeling cell walls and membranes. Here, we analyzed For1F, a novel gene that encodes a fusion of an exocyst subunit (Sec10) and an actin nucleation factor (formin). We showed that the fusion occurred early in moss evolution and has been retained for more than 170 million years. In Physcomitrella patens, For1F is essential, and the expressed protein is a fusion of Sec10 and formin. Reduction of For1F or actin filaments inhibits exocytosis, and For1F dynamically associates with Sec6, another exocyst subunit, in an actin-dependent manner. Complementation experiments demonstrate that constitutive expression of either half of the gene or the paralogous Sec10b rescues loss of For1F, suggesting that fusion of the two domains is not essential, consistent with findings in yeast, where formin and the exocyst are linked noncovalently. Although not essential, the fusion may have had selective advantages and provides a unique opportunity to probe actin regulation of exocytosis.
Keyphrases
  • cell migration
  • poor prognosis
  • copy number
  • genome wide
  • mouse model
  • binding protein
  • stem cells
  • bone marrow
  • transcription factor
  • small molecule
  • protein protein
  • living cells