A role for the dynamin-like protein Vps1 during endocytosis in yeast

Dynamins are a conserved family of proteins involved in membrane fusion and fission. Although mammalian dynamins are known to be involved in several membrane-trafficking events, the role of dynamin-1 in endocytosis is the best-characterised role of this protein family. Despite many similarities between endocytosis in yeast and mammalian cells, a comparable role for dynamins in yeast has not previously been demonstrated. The reported lack of involvement of dynamins in yeast endocytosis has raised questions over the general applicability of the current yeast model of endocytosis, and has also precluded studies using well-developed methods in yeast, to further our understanding of the mechanism of dynamin function during endocytosis. Here, we investigate the yeast dynamin-like protein Vps1 and demonstrate a transient burst of localisation to sites of endocytosis. Using live-cell imaging of endocytic reporters in strains lacking vps1, and also electron microscopy and biochemical approaches, we demonstrate a role for Vps1 in facilitating endocytic invagination. Vps1 mutants were generated, and analysis in several assays reveals a role for the C-terminal self-assembly domain in endocytosis but not in other membrane fission events with which Vps1 has previously been associated.