In the budding yeast, S. cerevisiae, Pil1 and another cytoplasmic protein, Lsp1, together form large immobile assemblies at the plasma membrane that mark sites for endocytosis, called eisosomes. Endocytosis functions to recycle plasma membrane components, to regulate cell-surface expression of signalling receptors and to internalise nutrients in all eukaryotic cells.

1: Eisosomes mark static sites of endocytosis. Walther TC, Brickner JH, Aguilar PS, Bernales S, Pantoja C, Walter P; Nature. 2006;439:998-1003. PMID:16496001

2: The filament-forming protein Pil1 assembles linear eisosomes in fission yeast. Kabeche R, Baldissard S, Hammond J, Howard L, Moseley JB; Mol Biol Cell. 2011;22:4059-4067. PMID:21900489