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William Stillwell - One of the best experts on this subject based on the ideXlab platform.
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Chapter 9 – Basic Membrane Properties of the Fluid Mosaic Model
An Introduction to Biological Membranes, 2020Co-Authors: William StillwellAbstract:Every aspect of membrane structural studies involves parameters that are very small and very fast. As a result a variety of highly specialized, usually esoteric biophysical methodologies must be employed, often simultaneously. It is the nature of the highly sophisticated techniques used to investigate membrane structure that unfortunately forms an almost insurmountable impediment between physical and biological approaches to membrane studies. This chapter will investigate several fundamental membrane properties using specific examples taken from the research literature. Emphasis will be placed on how the technique was employed to address a particular question. It is not the objective of this chapter, or this book, to discuss the intricate details of each technique, but rather to understand what questions the technique can address. In other words, the emphasis will be placed on application and not detailed methodology.
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Chapter 10 – Lipid Membrane Properties
An Introduction to Biological Membranes, 2020Co-Authors: William StillwellAbstract:The previous chapter ( Chapter 9) investigated some of the major principles of the “Fluid Mosaic” Model. While these principles form the core of understanding basic membrane structure, there are many other, more poorly understood membrane properties and concepts that must be considered. Membranes are just very complex. Several of these properties will be discussed in Chapters 10 and 11.
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Chapter 2 – Membrane History
An Introduction to Biological Membranes, 2020Co-Authors: William StillwellAbstract:The current concept of membrane structure is based on the Fluid Mosaic Model outlined by Singer and Nicolson in 1972. Not surprisingly, this Model did not just spring to life in a fully developed form but instead was conceived slowly over centuries. This chapter discusses the two seemingly unrelated but parallel historical paths taken: the study of oil on water and the study of the cell outer barrier (plasma membrane). These two approaches did not converge until the classic experiment of Gorter and Grendel in 1925.
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chapter 9 basic membrane properties of the Fluid Mosaic Model
An Introduction to Biological Membranes (Second Edition)#R##N#Composition Structure and Function, 2016Co-Authors: William StillwellAbstract:Every aspect of membrane structural studies involves parameters that are very small and very fast. As a result a variety of highly specialized, usually esoteric biophysical methodologies must be employed, often simultaneously. It is the nature of the highly sophisticated techniques used to investigate membrane structure that unfortunately forms an almost insurmountable impediment between physical and biological approaches to membrane studies. This chapter will investigate several fundamental membrane properties using specific examples taken from the research literature. Emphasis will be placed on how the technique was employed to address a particular question. It is not the objective of this chapter, or this book, to discuss the intricate details of each technique, but rather to understand what questions the technique can address. In other words, the emphasis will be placed on application and not detailed methodology.
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basic membrane properties of the Fluid Mosaic Model
An Introduction to Biological Membranes, 2013Co-Authors: William StillwellAbstract:Every aspect of membrane structural studies involves parameters that are very small and very fast. As a result a variety of highly specialized, usually esoteric biophysical methodologies must be employed, often simultaneously. It is the nature of the highly sophisticated techniques used to investigate membrane structure that unfortunately forms an almost insurmountable impediment between physical and biological approaches to membrane studies. This chapter will investigate several fundamental membrane properties using specific examples taken from the research literature. Emphasis will be placed on how the technique was employed to address a particular question. It is not the objective of this chapter, or this book, to discuss the intricate details of each technique, but rather to understand what questions the technique can address. In other words, the emphasis will be placed on application and not detailed methodology.
Garth L Nicolson - One of the best experts on this subject based on the ideXlab platform.
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the Fluid Mosaic Model of membrane structure still relevant to understanding the structure function and dynamics of biological membranes after more than 40 years
Biochimica et Biophysica Acta, 2014Co-Authors: Garth L NicolsonAbstract:Abstract In 1972 the Fluid—Mosaic Membrane Model of membrane structure was proposed based on thermodynamic principals of organization of membrane lipids and proteins and available evidence of asymmetry and lateral mobility within the membrane matrix [S. J. Singer and G. L. Nicolson, Science 175 (1972) 720–731]. After over 40 years, this basic Model of the cell membrane remains relevant for describing the basic nano-structures of a variety of intracellular and cellular membranes of plant and animal cells and lower forms of life. In the intervening years, however, new information has documented the importance and roles of specialized membrane domains, such as lipid rafts and protein/glycoprotein complexes, in describing the macrostructure, dynamics and functions of cellular membranes as well as the roles of membrane-associated cytoskeletal fences and extracellular matrix structures in limiting the lateral diffusion and range of motion of membrane components. These newer data build on the foundation of the original Model and add new layers of complexity and hierarchy, but the concepts described in the original Model are still applicable today. In updated versions of the Model more emphasis has been placed on the Mosaic nature of the macrostructure of cellular membranes where many protein and lipid components are limited in their rotational and lateral motilities in the membrane plane, especially in their natural states where lipid–lipid, protein–protein and lipid–protein interactions as well as cell–matrix, cell–cell and intracellular membrane-associated protein and cytoskeletal interactions are important in restraining the lateral motility and range of motion of particular membrane components. The formation of specialized membrane domains and the presence of tightly packed integral membrane protein complexes due to membrane-associated fences, fenceposts and other structures are considered very important in describing membrane dynamics and architecture. These structures along with membrane-associated cytoskeletal and extracellular structures maintain the long-range, non-random Mosaic macro-organization of membranes, while smaller membrane nano- and submicro-sized domains, such as lipid rafts and protein complexes, are important in maintaining specialized membrane structures that are in cooperative dynamic flux in a crowded membrane plane. This Article is Part of a Special Issue Entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
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update of the 1972 singer nicolson Fluid Mosaic Model of membrane structure
Discoveries (Craiova Romania), 2013Co-Authors: Garth L NicolsonAbstract:The Fluid-Mosaic Membrane Model of cell membrane structure was based on thermodynamic principals and the available data on component lateral mobility within the membrane plane [Singer SJ, Nicolson GL. The Fluid Mosaic Model of the structure of cell membranes. Science 1972; 175: 720-731]. After more than forty years the Model remains relevant for describing the basic nano-scale structures of a variety of biological membranes. More recent information, however, has shown the importance of specialized membrane domains, such as lipid rafts and protein complexes, in describing the macrostructure and dynamics of biological membranes. In addition, membrane-associated cytoskeletal structures and extracellular matrix also play roles in limiting the mobility and range of motion of membrane components and add new layers of complexity and hierarchy to the original Model. An updated Fluid-Mosaic Membrane Model is described, where more emphasis has been placed on the Mosaic nature of cellular membranes where protein and lipid components are more crowded and limited in their movements in the membrane plane by lipid-lipid, protein-protein and lipid-protein interactions as well as cell-matrix, cellcell and cytoskeletal interactions. These interactions are important in restraining membrane components and maintaining the unique Mosaic organization of cell membranes into functional, dynamic domains.
Ole G. Mouritsen - One of the best experts on this subject based on the ideXlab platform.
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is the Fluid Mosaic and the accompanying raft hypothesis a suitable Model to describe fundamental features of biological membranes what may be missing
Frontiers in Plant Science, 2013Co-Authors: Luis A. Bagatolli, Ole G. MouritsenAbstract:The structure, dynamics, and stability of lipid bilayers are controlled by thermodynamic forces, leading to overall tensionless membranes with a distinct lateral organization and a conspicuous lateral pressure profile. Bilayers are also subject to built-in curvature-stress instabilities that may be released locally or globally in terms of morphological changes leading to the formation of non-lamellar and curved structures. A key controller of the bilayer’s propensity to form curved structures is the average molecular shape of the different lipid molecules. Via the curvature stress, molecular shape mediates a coupling to membrane-protein function and provides a set of physical mechanisms for formation of lipid domains and laterally differentiated regions in the plane of the membrane. Unfortunately, these relevant physical features of membranes are often ignored in the most popular Models for biological membranes. Results from a number of experimental and theoretical studies emphasize the significance of these fundamental physical properties and call for a refinement of the Fluid Mosaic Model (and the accompanying raft hypothesis).
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An outlook on organization of lipids in membranes: searching for a realistic connection with the organization of biological membranes.
Progress in Lipid Research, 2010Co-Authors: Luis A. Bagatolli, John Hjort Ipsen, Adam Cohen Simonsen, Ole G. MouritsenAbstract:Lipid-bilayer membranes are formed by self-assembly processes. The molecular interactions within the bilayer and with the environment impart a unique trans-bilayer lateral pressure profile and provide a set of physical mechanisms for formation of lipid domains and laterally differentiated regions in the plane of the membrane. Results from a number of experimental and theoretical studies of Model lipid bilayers are reviewed, emphasizing the significance of these fundamental physical properties for the structure and dynamics of biological membranes. Particular attention is paid to the relevance of postulating the existence of equilibrium thermodynamic phases in biological membranes. This includes a discussion of the possible significance of equilibrium critical points in biological membrane systems that normally exist under non-equilibrium conditions. The need for a new Model to replace the celebrated Nicolson–Singer Fluid-Mosaic Model of biological membranes is also discussed.
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Role of Lipid Organization and Dynamics for Membrane Functionality
Biological Membranes, 1996Co-Authors: Ole G. Mouritsen, Paavo K.j. KinnunenAbstract:For almost 25 years the Singer-Nicolson Fluid-Mosaic Model of biological membranes (Singer and Nicolson, 1972) has been the central paradigm of membrane science. This Model, and the powerful and rather simple conceptual framework it provided to membrane scientists, have had a tremendous impact on advances in the broad field of biological membranes over the past more than two decades.
Kenichi G N Suzuki - One of the best experts on this subject based on the ideXlab platform.
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dynamic organizing principles of the plasma membrane that regulate signal transduction commemorating the fortieth anniversary of singer and nicolson s Fluid Mosaic Model
Annual Review of Cell and Developmental Biology, 2012Co-Authors: Akihiro Kusumi, Takahiro K Fujiwara, Rahul Chadda, Taka A Tsunoyama, Ziya Kalay, Rinshi S Kasai, Kenichi G N SuzukiAbstract:The recent rapid accumulation of knowledge on the dynamics and structure of the plasma membrane has prompted major modifications of the textbook Fluid-Mosaic Model. However, because the new data have been obtained in a variety of research contexts using various biological paradigms, the impact of the critical conceptual modifications on biomedical research and development has been limited. In this review, we try to synthesize our current biological, chemical, and physical knowledge about the plasma membrane to provide new fundamental organizing principles of this structure that underlie every molecular mechanism that realizes its functions. Special attention is paid to signal transduction function and the dynamic aspect of the organizing principles. We propose that the cooperative action of the hierarchical three-tiered mesoscale (2–300 nm) domains—actin-membrane-skeleton induced compartments (40–300 nm), raft domains (2–20 nm), and dynamic protein complex domains (3–10 nm)—is critical for membrane functi...
Akihiro Kusumi - One of the best experts on this subject based on the ideXlab platform.
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dynamic organizing principles of the plasma membrane that regulate signal transduction commemorating the fortieth anniversary of singer and nicolson s Fluid Mosaic Model
Annual Review of Cell and Developmental Biology, 2012Co-Authors: Akihiro Kusumi, Takahiro K Fujiwara, Rahul Chadda, Taka A Tsunoyama, Ziya Kalay, Rinshi S Kasai, Kenichi G N SuzukiAbstract:The recent rapid accumulation of knowledge on the dynamics and structure of the plasma membrane has prompted major modifications of the textbook Fluid-Mosaic Model. However, because the new data have been obtained in a variety of research contexts using various biological paradigms, the impact of the critical conceptual modifications on biomedical research and development has been limited. In this review, we try to synthesize our current biological, chemical, and physical knowledge about the plasma membrane to provide new fundamental organizing principles of this structure that underlie every molecular mechanism that realizes its functions. Special attention is paid to signal transduction function and the dynamic aspect of the organizing principles. We propose that the cooperative action of the hierarchical three-tiered mesoscale (2–300 nm) domains—actin-membrane-skeleton induced compartments (40–300 nm), raft domains (2–20 nm), and dynamic protein complex domains (3–10 nm)—is critical for membrane functi...