Structure, Dynamics, and Biogenesis of Biomembranes

Biomembranes are not only principal constituents of the cell but also a major site of biological activity. Studies on biomembranes are therefore, crucial for furthering our understanding of life processes. A special research project on biomembranes involving more than 100 in­ vestigators was conducted under a grant from the Ministry of Education, Science and Culture of Japan between 1978 and 1981. This has resulted in marked progress on basic biomedical studies on biomembranes in Japan. This book is a compilation of several major developments made during this project in the field of "Structure, Dynamics, and Biogenesis of Biomembranes. " Developments in other fields constitute the contents of a companion volume, "Transport and Bioenergetics in Biomembranes," edited by Sato and Kagawa. In these two volumes the authors review recent advances which have been primarily made in their own labora­ tories and include relevant work carried out by other investigators. Eight topics are presented in this volume. Ikegami and coworkers review molecular dynamics in lipid bilayers, reconstituted membranes and biological membranes as studied by nanosecond fluorescence spec­ troscopy with an emphasis on the wobbling in the cone model. The fol­ lowing two chapters deal with virus-induced membrane fusions. Ohnishi and Maeda describe an assay method for envelope fusion using spin­ labeled phospholipids and report several characteristic results obtained by this method including low pH-induced fusion of influenza virus.

Structure and Dynamics of Biological Membranes Studied by Nanosecond Fluorescence Spectroscopy.- I. Wobbling Motion of the Hydrocarbon Chains in Lipid Bilayers.- 1. Nanosecond fluorescence depolarization and wobbling in cone model.- 2. Phase transition of lipid hydrocarbon chains.- 3. Effect of double bonds.- 4. Effect of cholesterol.- II. Protein-lipid Interaction: The Case of Cytochrome Oxidase.- 1. Conformational changes in cytochrome oxidase.- 2. Effect of cytochrome oxidase on lipid dynamics.- III. Chromophore in Bacteriorhodopsin.- 1. Immobility of the chromophore in the binding site.- 2. Location and orientation of the chromophore in the purple membrane.- IV. Dynamic Structure of Biological Membranes.- Summary.- Interaction of Enveloped Virus with Cell Membranes: A Spin Label Study.- I. Methods.- 1. Transfer of phospholipids from virus envelope to target cell membranes.- 2. Release to tempocholine from preloaded virus particles.- 3. Assay of endocytized virus particles.- II. Analysis of Phospholipid Transfer and Tempocholine Release Based on Envelope Fusion.- III. Phospholipid Transfer via Exchange between Virus Envelope and Cell Membrane.- IV. Envelope Fusion of Influenza Virus Is Activated under Mildly Acidic Conditions.- Summary.- Mechanism of HVJ-Induced Cell Fusion.- I. Virus and Cells.- II. Reaction Steps of Virus-induced Fusion Reaction.- III. Structure-function Relationship of F Glycoprotein Required for Fusion.- IV. Structure-function Relationship of HANA Glycoprotein.- V. Effects of Lipid Composition on Fusion Reaction.- VI. Intracellular Factors Which Control Fusion-undergoing Ability of Cells.- VII. Changes in Membrane Structure Relevant to Cell-cell Fusion.- Summary.- Transmembrane Control of the Mobility of Surface Receptors by Cytoskeletal Structures.- I. Interrelation between Cell Surface Receptors and Cytoplasmic MT.- 1. Restriction of the mobility of receptors by concanavalin A (Con A) and its reversion by colchicine.- 2. A hypothesis for the control of receptor movement by cytoplasmic MT.- 3. Visualization of the MT network in lymphocytes by immunofluorescence microscopy using antitubulin antibody.- 4. Modulation of MT organization by patching and capping.- II. Mechanism of Capping: An Alteration of Microfilamentous Organizations Associated with Redistribution of Surface Receptors.- 1. Ligand-independent (LI) capping induced in hypertonic medium.- 2. Mechanism of translocation of microvilli accompanying capping of surface receptors.- Summary.- Structures of the Sugar Chains of Cell Surface Glycoproteins.- I. Structures of Mucin-type Sugar Chains.- II. Structures of Asparagine-linked Sugar Chains.- III. Species-specific Structural Differences in the Outer Chain Moiety of Complex-type Asparagine-linked Sugar Chains.- IV. Problem of Microheterogeneity of the Sugar Chains of Glycoproteins.- Summary.- Structure and Function of Outer Membrane of Escherichia Coli: A Reconstitution Study.- I. Components of Outer Membrane.- II. Properties of Major Outer Membrane Proteins.- 1. The lipoprotein.- 2. OmpF and OmpC.- 3. OmpA.- III. Reconstitution of Outer Membrane.- IV. Interaction between Outer Membrane Proteins and LPS.- V. Roles of Cell Surface Components of E. coli K-12 in Bacteriophage Infection.- Summary.- Synthesis and Translocation of Mitochondrial Matrix Enzymes in Higher Animals with Special Reference to ?-Aminolevulinate Synthase.- I. Synthesis and Intracellular Translocation of ALA Synthase.- 1. Induction of synthesis of ALA synthase in rat liver.- 2. Inhibition of intracellular translocation of ALA synthase by heme.- 3. Inhibition of ALA synthase synthesis by heme.- 4. Possible processing of ALA synthase.- 5. Physiological significance of the regulatory effects of heme on ALA synthase.- II. Synthesis and Intracellular Translocation of Other Matrix Enzymes.- 1. Glutamate dehydrogenase and malate dehydrogenase.- 2. Carbamoyl phosphate synthetase and ornithine transcarbamoylase.- 3. Aspartate aminotransferase.- 4. Serine aminotransferase.- 5. Ornithine aminotransferase.- 6. Fumarase.- 7. Glycerate kinase.- 8. Phosphoenolpyruvate carboxykinase.- 9. Adrenodoxin and adrenodoxin reductase.- III. Comments.- Summary.- Biogenesis of the Membrane of Endoplasmic Reticulum.- I. Turnover of Microsomal Membrane Proteins in Animal Liver.- II. Biosynthesis of Microsomal Membrane Proteins.- III. Integration of Newly Synthesized Proteins into Endoplasmic Reticulum Membrane.- Summary.