Study of biophysical properties of giant unilamellar vesicles as model for intracellular delivery of material: membrane electroporation and fusion

• Grant number: 11/22171-6
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2012
• End date: October 04, 2016
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Karin Do Amaral Riske
• Grantee: Rafael Bezerra de Lira
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated scholarship(s): 13/07246-5 - Electroporation and fusion of electrically charged vesicles, BE.EP.DR

Abstract

Membranes are responsible for many cellular processes, including selective entry of nutrients and energy production. The development of systems that emulate diverse properties of biological membranes and further free of their inherent complexity are fundamental for the understanding of various phenomenon that depend on the membranes. Among such model systems are the giant unilamellar vesicles (GUVs), which can mimic many aspects of natural membranes in a simplified way and provide the possibility to study diverse events directly on the microscope. In the present project, we propose the use of GUVs to study of the effect of membrane composition and the surrounding medium in basic processes of the two main methods for intracellular delivery of materials: (1) electroporation and (2) membrane fusion. In (1) the vesicles will be submitted to an electrical pulse and the conditions in which membrane electropermeabilization or bursting of the whole vesicle will be studied. In (2) small fusogenic liposomes will be incubated with GUVs and our aim is to understand the role of the lipids in the mechanisms of membrane fusion. Further, this approach can allow the development of a exocytic biomimetic system. In virtually all the experimental conditions, measurements of the membrane line tension, viscosity and diffusion coefficient of fluorescent probes in the membrane will be investigated. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

LIRA, RAFAEL B.; ROBINSON, TOM; DIMOVA, RUMIANA; RISKE, KARIN A.. Highly Efficient Protein-free Membrane Fusion: A Giant Vesicle Study. BIOPHYSICAL JOURNAL, v. 116, n. 1, p. 79-91, JAN 8 2019. (11/22171-6, 16/13368-4, 13/07246-5)

LIRA, RAFAEL B.; LEOMIL, FERNANDA S. C.; MELO, RENAN J.; RISKE, KARIN A.; DIMOVA, RUMIANA. To Close or to Collapse: The Role of Charges on Membrane Stability upon Pore Formation. ADVANCED SCIENCE, v. 8, n. 11, MAR 2021. (11/22171-6, 16/13368-4, 13/07246-5)

LIRA, RAFAEL B.; STEINKUEHLER, JAN; KNORR, ROLAND L.; DIMOVA, RUMIANA; RISKE, KARIN A.. Posing for a picture: vesicle immobilization in agarose gel. SCIENTIFIC REPORTS, v. 6, MAY 3 2016. (11/22171-6, 13/07246-5)

MATTEI, BRUNO; LIRA, RAFAEL B.; PEREZ, KATIA R.; RISKE, KARIN A.. Membrane permeabilization induced by Triton X-100: The role of membrane phase state and edge tension. Chemistry and Physics of Lipids, v. 202, p. 28-37, JAN 2017. (13/20499-0, 11/22171-6)