We recently published two new studies on quantitative analysis of clathrin-mediated endocytosis in fission yeast:
Molecular Biology of the Cell. 2014 Nov 5;25(22):3501-14. PMID: 25143395
Berro J and Pollard TD. Synergies between Aip1p and capping protein subunits (Acp1p and Acp2p) in clathrin mediated endocytosis and cell polarization in fission yeast. Molecular Biology of the Cell. 2014 Nov 5;25(22):3515-27. PMID: 25143407
The first paper presents new methods to collect and analyze quantitative microscopy data. We describe a new “temporal super-resolution” method to realign datasets obtained with low temporal resolution and reconstruct a signal with higher temporal resolution. This method allowed us to demonstrate the high reproducibility of endocytic events in fission yeast, and to show that endocytic vesicles move with a diffusive motion that is modulated by actin disassembly. In this paper, we also present a new method to automatically estimate the number of endocytic events in a cell at a given time point.
Application of these new methods allowed us to demonstrate in a second paper that Aip1p caps the barbed ends of actin filaments in a specific context and can be replaced by the canonical capping protein heterodimer Acp1p/Acp2p. However, Aip1p cannot replace Acp1p/Acp2p. Our data also point out new independent functions for Acp1p and Acp2p in cell polarity. Finally, our quantitative analysis allowed us to infer geometric properties of the endocytic structures and to show that the actin meshwork compresses before scission of the endocytic vesicle.