1a as it appears in virtually all biochemistry texts. The model has become the standard conceptualization of membrane architecture and is shown redrawn in Fig. To develop these themes fully would require a much longer text (perhaps a book?), so only representative references are given here, and use is made of the references in the longer treatments by the other authors.Īn influential step in the study of membranes was taken with the development by Singer and Nicholson in 1972 of the ‘fluid mosaic model’ 1, which pulled together findings and ideas from the preceding decade.
To frame a context for the reviews that follow, a few general perspectives are presented briefly below. Further refinements led to the use of the barrier for its energy-storage properties and to the creation of ways to pass information between a cell and its environment. Thus, the lipid bilayer, which spontaneously forms permeability barriers surrounding aqueous interiors, must be modified by macromolecules for the uptake of nutrients and the disposal of waste. In the case of membranes, we might start with the origin of life, noting that compartmentalization is essential for an organism, and that with compartmentalization must come specific ways to surmount the barrier defining the boundary of the compartment - the membrane. The reductionist view of biology, to which many adhere, rests in part on the structure–function hypothesis: that the structures we find are there for specific functional reasons selected by evolution. Articles in this Insight expose current views of the importance, findings and concepts in membrane biology in some regions of the emerging landscape. This is leading to a great expansion of interest in the area.
But now we have a rising number of high-resolution structures, an abundance of functional data and an evolving conceptual basis for framing more pointed questions. Most methods require purification and observation in aqueous environments alien to the molecular design of a membrane, and so the field had to rely on oversimplified views that still dominate the texts and teaching in this area. Perhaps this is understandable in view of the technical hurdles that working with them presents. Given their biological importance, membranes have been surprisingly neglected by biochemists until recently.
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