title: Single particle fluorescence burst analysis of epsin induced membrane fission.
abstract: Vital cellular processes, from cell growth to synaptic transmission, rely on membrane-bounded carriers and vesicles to transport molecular cargo to and from specific intracellular compartments throughout the cell. Compartment-specific proteins are required for the final step, membrane fission, which releases the transport carrier from the intracellular compartment. The role of fission proteins, especially at intracellular locations and in non-neuronal cells, while informed by the dynamin-1 paradigm, remains to be resolved. In this study, we introduce a highly sensitive approach for the identification and analysis of membrane fission machinery, called burst analysis spectroscopy (BAS). BAS is a single particle, free-solution approach, well suited for quantitative measurements of membrane dynamics. Here, we use BAS to analyze membrane fission induced by the potent, fission-active ENTH domain of epsin. Using this method, we obtained temperature-dependent, time-resolved measurements of liposome size and concentration changes, even at sub-micromolar concentration of the epsin ENTH domain. We also uncovered, at 37°C, fission activity for the full-length epsin protein, supporting the argument that the membrane-fission activity observed with the ENTH domain represents a native function of the full-length epsin protein.
authors: Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America.
authors: Arielle
authors: A
authors: Brooks
authors: Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America.
authors: Daniel
authors: D
authors: Shoup
authors: Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America.
authors: Lauren
authors: L
authors: Kustigian
authors: Department of Physics, Princeton University, Princeton, New Jersey, United States of America.
authors: Jason
authors: J
authors: Puchalla
authors: Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America.
authors: Chavela M
authors: CM
authors: Carr
authors: Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America.
authors: Hays S
authors: HS
authors: Rye
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000737:chemistry* / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D004705:Endocytosis / Q000502:physiology*; D005453:Fluorescence; D057927:Hydrophobic and Hydrophilic Interactions; D007425:Intracellular Membranes / Q000378:metabolism*; D008081:Liposomes / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D051381:Rats
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D008081:Liposomes; C114154:epsin