Membrane Fusion: Mechanisms and Simulations

In course

Description

This lecture explores the process of vesicle fusion, detailing the steps involved such as membrane bending, merging, and rupture. It delves into the role of polyunsaturated phospholipids in lowering the energy cost of bending, the function of SNARE proteins in driving fusion pore formation, and the impact of external forces on membrane fusion. Through simulations and experimental evidence, the instructor discusses the molecular mechanisms behind vesicle fusion, the importance of specific lipid properties, and the challenges in studying the complex process. The lecture also covers the biology of Shigella infection, the clustering of STXB on membranes, and the formation of tubular invaginations. Overall, it provides insights into the biophysics of cellular processes and the interdisciplinary nature of studying membrane fusion.

Instructor

Official source

https://mediaspace.epfl.ch/media/0_88xjf3ib

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related lectures (12)

Related concepts (56)

Membrane biology

Membrane biology is the study of the biological and physiochemical characteristics of membranes, with applications in the study of cellular physiology. Membrane bioelectrical impulses are described by the Hodgkin cycle. Membrane biophysics is the study of biological membrane structure and function using physical, computational, mathematical, and biophysical methods. A combination of these methods can be used to create phase diagrams of different types of membranes, which yields information on thermodynamic behavior of a membrane and its components.

Cell membrane

The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extracellular space). The cell membrane consists of a lipid bilayer, made up of two layers of phospholipids with cholesterols (a lipid component) interspersed between them, maintaining appropriate membrane fluidity at various temperatures.

Lipid bilayer

The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells. The cell membranes of almost all organisms and many viruses are made of a lipid bilayer, as are the nuclear membrane surrounding the cell nucleus, and membranes of the membrane-bound organelles in the cell. The lipid bilayer is the barrier that keeps ions, proteins and other molecules where they are needed and prevents them from diffusing into areas where they should not be.

Vesicle fusion

Vesicle fusion is the merging of a vesicle with other vesicles or a part of a cell membrane. In the latter case, it is the end stage of secretion from secretory vesicles, where their contents are expelled from the cell through exocytosis. Vesicles can also fuse with other target cell compartments, such as a lysosome. Exocytosis occurs when secretory vesicles transiently dock and fuse at the base of cup-shaped structures at the cell plasma membrane called porosome, the universal secretory machinery in cells.

Membrane vesicle trafficking

Membrane vesicle trafficking in eukaryotic animal cells involves movement of biochemical signal molecules from synthesis-and-packaging locations in the Golgi body to specific release locations on the inside of the plasma membrane of the secretory cell. It takes place in the form of Golgi membrane-bound micro-sized vesicles, termed membrane vesicles (MVs). In this process, the packed cellular products are released or secreted outside the cell, across its plasma membrane.