Fluid mosaic model of cell membrane

Singer, S.J., and G.L. Nicolson. 1972. The fluid mosaic model of cell membranes. Science 175 720. 

FIGURE 26.2 Schematic fluid mosaic model of cell membrane structure. 

According to the fluid mosaic model of cell membranes, which type of molecule spans the membrane, from its inner to outer surface ... 

Cell Membranes The sequence of models of membrane structure Danielli-Davson Robertson S inger-N icholson The fluid mosaic model of cell membrane structure The interplay between data and models in the development of models of cell structure... 

At the beginning of Alison s lesson, students mention the fluid mosaic model of cell membrane strueture. This model features elsewhere in their science course and is a standard model introduced in text books, at this level in which lipids are free to move within the eell wall. The class is discussing data suggesting a 2 1 ratio between the surface area occupied by lipids extracted from a cell and die surface area of that cell. As yet none of the three models of membrane structnre has been presented. 

Wisniewska, A., J. Draus, and W. K. Subczynski. 2006. Is fluid mosaic model of biological membranes fully relevant Studies on lipid organization in model and biological membranes. Cell. Mol. Biol. Lett. 8 147-154. 

While the fluid mosaic model of membrane stmcture has stood up well to detailed scrutiny, additional features of membrane structure and function are constantly emerging. Two structures of particular current interest, located in surface membranes, are tipid rafts and caveolae. The former are dynamic areas of the exo-plasmic leaflet of the lipid bilayer enriched in cholesterol and sphingolipids they are involved in signal transduction and possibly other processes. Caveolae may derive from lipid rafts. Many if not all of them contain the protein caveolin-1, which may be involved in their formation from rafts. Caveolae are observable by electron microscopy as flask-shaped indentations of the cell membrane. Proteins detected in caveolae include various components of the signal-transduction system (eg, the insutin receptor and some G proteins), the folate receptor, and endothetial nitric oxide synthase (eNOS). Caveolae and lipid rafts are active areas of research, and ideas concerning them and their possible roles in various diseases are rapidly evolving. 

Fig. 7 Diagrammatic representation of the fluid mosaic model of the cell membrane. The basic structure of the membrane is that of a lipid bilayer in which the lipid portion (long tails) points inward and the polar portion (round head ) points outward. The membrane is penenetrated by transmembrane (or integral) proteins. Attached to the surface of the membrane are peripheral proteins (inner surface) and carbohydrates that bind to lipid and protein molecules (outer surface). (Modified from Ref. 14.)...

Figure 8.15 is a sketch of one possible relationship between the lipid bilayer and the membrane proteins. Molecules are free to move laterally in these membranes hence the structure pictured in Figure 8.15 is called the fluid mosaic model of a cell membrane. 

Cel Membrane. The fluid mosaic model of the cell membrane is one in which the phospholipids provide the basic order and integrity of the cell through amphiphilic interaction with the aqueous environment. 

The fluid-mosaic model for biological membranes as envisioned by Singer and Nicolson. Integral membrane proteins are embedded in the lipid bilayer peripheral proteins are attached more loosely to protruding regions of the integral proteins. The proteins are free to diffuse laterally or to rotate about an axis perpendicular to the plane of the membrane. For further information, see S. J. Singer and G. L. Nicolson, The fluid mosaic model of the structure of cell membranes, Science 175 720, 1972. 

S.J. Singer, G.L. Nicolson, Fluid Mosaic Model of Structure of Cell Membranes , Science, 175,720 (1972)... 

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