Cholesterol Binding and Cholesterol Transport Proteins: (eBook)

Structure and Function in Health and Disease

J. Robin Harris (Herausgeber)

eBook Download: PDF

2010 | 2010
XXII, 632 Seiten
Springer Netherland (Verlag)
978-90-481-8622-8 (ISBN)

Infos

Knowledge of cholesterol and its interaction with protein molecules is of fundamental importance in both animal and human biology. This book contains 22 chapters, dealing in depth with structural and functional aspects of the currently known and extremely diverse unrelated families of cholesterol-binding and cholesterol transport proteins. By drawing together this range of topics the Editor has attempted to correlate this broad field of study for the first time. Technical aspects are given considerable emphasis, particularly in relation cholesterol reporter molecules and to the isolation and study of membrane cholesterol- and sphingomyelin-rich 'raft' domains. Cell biological, biochemical and clinical topics are included in this book, which serve to emphasize the acknowledged and important benefits to be gained from the study of cholesterol and cholesterol-binding proteins within the biomedical sciences and the involvement of cholesterol in several clinical disorders.

It is hoped that by presenting this topic in this integrated manner that an appreciation of the fact that there is much more that needs to be taken into account, studied and understood than the widely discussed 'bad and good cholesterol' associated, respectively, with the low- and high-density lipoproteins, LDL and HDL.

---

Knowledge of cholesterol and its interaction with protein molecules is of fundamental importance in both animal and human biology. This book contains 22 chapters, dealing in depth with structural and functional aspects of the currently known and extremely diverse unrelated families of cholesterol-binding and cholesterol transport proteins. By drawing together this range of topics the Editor has attempted to correlate this broad field of study for the first time. Technical aspects are given considerable emphasis, particularly in relation cholesterol reporter molecules and to the isolation and study of membrane cholesterol- and sphingomyelin-rich "e;raft"e; domains. Cell biological, biochemical and clinical topics are included in this book, which serve to emphasize the acknowledged and important benefits to be gained from the study of cholesterol and cholesterol-binding proteins within the biomedical sciences and the involvement of cholesterol in several clinical disorders.It is hoped that by presenting this topic in this integrated manner that an appreciation of the fact that there is much more that needs to be taken into account, studied and understood than the widely discussed "e;bad and good cholesterol"e; associated, respectively, with the low- and high-density lipoproteins, LDL and HDL.

Inhalt

Frontispiece 8
Preface 10
Contents 14
Contributors 18
1 CholesterolProtein Interaction: Methods and Cholesterol Reporter Molecules 23
1.1 Introduction 24
1.2 Cholesterol-Rich Microdomains 27
1.2.1 Detergent-Based Methods 28
1.2.2 Detergent-Free Methods 29
1.2.3 Receptors in Cholesterol-Rich Microdomains (Lipid Rafts) 30
1.3 Manipulation of the Membrane Cholesterol Content by Cyclodextrins 31
1.4 Cholesterol-Binding Molecules 35
1.4.1 Polyenes 35
1.4.2 Cholesterol-Dependent Cytolysins 37
1.4.3 Enzymes with Cholesterol as Substrate 38
1.4.4 Other Cholesterol-binding Proteins 40
1.5 Binding Studies with Radiolabelled Cholesterol 42
1.6 Fluorescent Cholesterol Analogues 43
1.6.1 Dehydroergosterol 44
1.6.2 Cholestatrienol 47
1.6.3 NBD-Cholesterol 48
1.6.4 Bodipy-Cholesterol 49
1.6.5 Fluorescent PEG-Cholesterol 50
1.6.6 Dansyl-Cholestanol 50
1.7 Spin-Labelled Cholesterol 51
1.8 Affinity Labelling with Photoreactive Cholesterol 51
1.9 Concluding Remarks 54
References 55
2 Cholesterol in Alzheimer's Disease and other Amyloidogenic Disorders 68
2.1 Introduction 68
2.2 Cholesterol Metabolism and Alzheimers Disease 69
2.3 Cholesterol Binding to Aß and Aß Fibrillogenesis 72
2.3.1 Cholesterol and Membrane-Associated Aß Pore Formation and Fibrillogenesis 73
2.3.2 Gangliosides and Aß Fibrillogenesis 74
2.3.3 Cholesterol and In Vitro Aß Fibrillogenesis: Structural Studies 74
2.4 Apolipoprotein E, Cholesterol and Alzheimers Disease 78
2.5 Cholesterol Oxidation and Alzheimers Disease 81
2.6 Atherosclerosis and Alzheimers Disease 83
2.7 Cholesterol and Tau Fibrillization in AD, the Tauopathies and Non-A Amyloidogenic Disorders 84
2.8 Conclusions 86
References 86
3 Cholesterol-Binding Viral Proteins in Virus Entry and Morphogenesis 97
3.1 Introduction 99
3.1.1 Virus Lipidomics 100
3.1.2 Cholesterol Binding Sites 101
3.1.3 Methods Demonstrating Protein--Cholesterol Binding 102
3.2 Human Immunodeficiency Virus Fusion Protein gp41 105
3.2.1 Mutational Studies on the Pre-TM CRAC Motif in Virus-Cell Systems 106
3.2.2 Studies on Full-Length gp160, gp41 and Polypeptide Constructs 108
3.2.3 Peptide Studies and Modelling 108
3.3 Infuenza Virus M2 Protein 110
3.3.1 Influenza Virus Entry and Egress 110
3.3.2 M2 Protein Structural and Functional Domains 110
3.3.3 Influenza Virus Membrane Rafts 112
3.3.4 Cholesterol in the Apical Transport and Maturation of M2 Protein 112
3.3.5 M2 Protein-Cholesterol Binding Experiments 113
3.3.6 Membrane Raft Binding Determinants and CRAC Motifs in the Post-TM 114
3.3.7 Morphogenesis and Budding 116
3.3.8 Incorporation of M2 into Virus Particles and the Process of Membrane Fission 117
3.4 Fusion Proteins of Alphavirus Species 118
3.5 Other Cholesterol-Binding Virus Proteins 119
3.6 Conclusions 119
References 120
4 Sterol--Protein Interactions in Cholesterol and BileAcid Synthesis 129
4.1 Introduction 130
4.2 Brief Overview of Cholesterol and Bile Acid Biosynthesis 131
4.3 The Binding of (Chole)sterols to Cytochrome P450 Enzymes: Highly Stringent and Less Stringent EnzymeSubstrate Interactions 133
4.4 Bile AcidProtein Interactions: The Molecular Mechanisms Underlying Bile Acid Synthesis Feedback Regulation and Beyond 135
4.5 The Liver X Receptor: Sterol or Non-sterol, This Is the Question 140
4.6 Interactions Between Sterols and Sterol-Sensing Proteins Dictate Their Fate Toward Retention in the Endoplasmic Reticulum 143
4.7 Interactions Between Sterols and Sterol-Sensing Proteins Dictate their Fate Toward Degradation 147
4.8 Summary 148
4.9 Conclusions 150
References 150
5 Cholesterol Oxidase: Structure and Function 156
5.1 Introduction 156
5.2 Forms of Cholesterol Oxidase 157
5.3 Applications of Cholesterol Oxidase 159
5.4 Redox Properties of Cholesterol Oxidase 161
5.5 Structure Characterization 162
5.5.1 Non-covalent Enzyme Structure 162
5.5.2 Covalent Enzyme Structure 164
5.6 Catalytic Mechanism 165
5.6.1 Non-covalent Enzyme Mechanism 165
5.6.2 Covalent Enzyme Mechanism 168
5.7 Oxygen Channel 169
References 172
6 Oxysterol-Binding Proteins 178
6.1 Introduction 179
6.2 Pathways of Intracellular Cholesterol Transport 179
6.3 Cholesterol Transfer by Soluble Binding Proteins 180
6.4 Oxysterol-Binding Protein (OSBP) and OSBP-Related Proteins (ORPs) 181
6.5 Phylogenetic Distribution of OSBP/ORPs 181
6.6 Structural Organization of the OSBP/ORP Family 183
6.6.1 Ligand Binding Domain 183
6.6.2 Organelle-Specific Targeting Domains 184
6.7 Role of Mammalian OSBP/ORPs in Sterol Transport and Signalling 185
6.7.1 OSBP 186
6.7.2 ORP1 189
6.7.3 ORP2 189
6.7.4 ORP3, ORP6 and ORP7 190
6.7.5 ORP4 191
6.7.6 ORP5 and ORP8 191
6.7.7 ORP9 192
6.7.8 ORP10 and ORP11 193
6.8 Summary and Conclusions 193
References 194
7 High Density Lipoprotein StructureFunction and Role in Reverse Cholesterol Transport 202
7.1 Introduction 203
7.2 Structures of ApoA-I and ApoE in the Lipid-Free State 204
7.2.1 Primary and Secondary Structures 204
7.2.2 Tertiary Structure 206
7.2.3 Quaternary Structure 209
7.3 Interaction of ApoA-I and ApoE with Lipids 210
7.3.1 Molecular Mechanism of Lipid-Binding 210
7.3.2 Apolipoprotein Conformation in Discoidal and Spherical HDL Particles 212
7.3.3 Remodeling of HDL Particles 214
7.4 Lipid Solubilizing Properties of ApoA-1 andApoE 216
7.4.1 Historical Perspective 216
7.4.2 Mechanism of Solubilization Reaction 218
7.4.3 Influence of Apolipoprotein Structure 220
7.5 HDL and Reverse Cholesterol Transport (RCT) 221
7.5.1 Overview of RCT Pathway -- HDL Species and Receptors Involved 221
7.5.2 ABCA1 223
7.5.3 SR-BI 226
7.5.4 ApoE-HDL 229
7.6 HDL and Inflammation 231
7.6.1 Serum Amyloid A 231
7.7 Summary and Conclusions 232
References 233
8 Lipoprotein Modification and Macrophage Uptake: Role of Pathologic Cholesterol Transport in Atherogenesis 247
8.1 Introduction 248
8.1.1 Physiologic Role of LDL in Cholesterol Transport 248
8.1.2 Atherosclerosis and the LDL Paradox. Modified LDL 249
8.2 Mechanisms of LDL Oxidation and Enzymatic Degradation 250
8.3 Box 8.1 Evidence that LDL undergoes oxidation in vivo 250
8.2.1 LDL Oxidation by Copper 251
8.2.2 LDL Oxidation by Heme 252
8.2.3 Enzymatic and Cell-Mediated Oxidation of LDL 253
8.2.3.1 12/15-Lipoxygenase 253
8.2.3.2 Myeloperoxidase 254
8.2.3.3 Endothelial and Inducible Nitric Oxide Synthases and NADPH Oxidases 255
8.2.4 Non-oxidative Enzymatic Modifications of LDL 256
8.3 Macrophage Uptake of Modified LDL 256
8.4 Box 8.2 Major pathways mediating uptake of modified LDL by macrophages 256
8.3.1 Pattern-Recognition Receptors 257
8.3.1.1 CD36, SR-A and Other Scavenger Receptors 257
8.3.1.2 TLR4 and Macropinocytosis 259
8.3.1.3 Immune and Complement Complexes 260
8.3.2 Constitutive Macropinocytosis 260
8.3.3 Phagocytosis and Patocytosis of Aggregated LDL 260
8.3.4 LDLR Family Receptor-Mediated Uptake 261
8.4 Future Directions 261
8.4.1 Zebrafish Model for Studying Early Events in Atherogenesis 261
8.5 Summary 262
References 262
9 Cholesterol Interaction with Proteins That Partition into Membrane Domains: An Overview 270
9.1 Lipid Mixtures That Spontaneously Segregate into Cholesterol-Rich Domains 270
9.1.1 Lipid Mixtures Exhibiting Liquid--Liquid Phase Immiscibility 271
9.1.2 The Liquid Ordered Phase 271
9.1.3 Comparison Between the Domains Formed in Simple Lipid Mixtures and Those of Biological Membranes 271
9.1.4 Detection of Rafts in Biological Membranes 273
9.1.5 Properties of Rafts in Biological Membranes 273
9.1.6 Transbilayer Coupling and Rafts 274
9.2 Perturbation of Phase Behaviour by Proteins 275
9.3 Proteins Favouring Colocalization with Cholesterol 275
9.3.1 Lipidated Proteins 276
9.3.2 CRAC Motif 277
9.3.3 Sterol-Sensing Domains 285
9.4 Summary and Future Perspectives 287
References 288
10 Caveolin, Sterol Carrier Protein-2, MembraneCholesterol-Rich Microdomains and Intracellular Cholesterol Trafficking 296
10.1 Introduction 297
10.2 What Are Cholesterol-Rich and -Poor Microdomains? 297
10.3 How Is Cholesterol Organized Within Plasma Membranes? 299
10.4 What Are the Dynamics of Cholesterol Efflux in Cholesterol-Rich Versus -Poor Microdomains? 300
10.5 Does Membrane Lipid Composition Affect Cholesterol Dynamics in Cholesterol-Rich and -Poor Microdomains? 301
10.6 How May Plasma Membrane Proteins Regulate Cholesterol Dynamics? 302
10.7 How May Intracellular Cholesterol-Binding Proteins Regulate Cholesterol Dynamics? 303
10.7.1 Sterol Carrier Protein-2 (SCP-2) 304
10.7.2 Liver Fatty Acid-Binding Protein (L-FABP) 304
10.7.3 Steroidogenic Acute Regulatory Related (START) Proteins 305
10.7.4 Oxysterol Related Proteins (ORP) 305
10.7.5 Niemann Pick C (NPC) Proteins 305
10.7.6 Other Intracellular Proteins 306
10.8 Sterol Carrier Protein-2 Facilitates Intermembrane Cholesterol Transfer In Vitro 306
10.9 Do Cholesterol-Rich and -Poor Microdomains Exist in the Plasma Membranes of Living Cells: Real-Time Multiphoton Imaging of a Naturally Fluorescent Sterol (Dehydroergosterol, DHE)? 307
10.10 Can the Existence of Cholesterol-Rich and -Poor Microdomains in Plasma Membranes of Living Cells Be Confirmed by Other Real-Time Approaches Using Synthetic Fluorescent Sterols Suitable for Confocal Imaging? 308
10.10.1 Colocalization of DChol with the Lipid-Rich Microdomain Marker GM 1 309
10.10.2 DChol Colocalization and Fluorescence Resonance Energy Transfer (FRET) with DiD, a Liquid Ordered Phase Lipid-Rich Microdomain Marker 310
10.10.3 FRET Between DChol and DHE in Living Cells 312
10.10.4 Colocalization and Fluorescence Resonance Energy Transfer (FRET) Between DChol and BC 313
10.10.5 Weak Colocalization and Absence of Fluorescence Resonance Energy Transfer (FRET) Between DChol and N-Rh-DOPE 314
10.11 Real-Time Imaging of Sterol Carrier Protein-2 Mediated Cholesterol Dynamics Through Cholesterol-Rich and -Poor Microdomains in Plasma Membranes of Cultured Cells 314
10.12 Physiological Studies of Effects of SCP-2 Overexpression and Gene Ablation on Cholesterol Dynamics 317
10.12.1 Effects of SCP-2 Over-Expression and Antisense Treatment on Hepatic and Biliary Cholesterol 318
10.12.2 Effects of SCP-2/SCP-x Gene Ablation on Hepatic and Biliary Cholesterol 318
10.13 Potential Compensation by Other Cholesterol-binding Proteins 319
10.14 Conclusions and Future Perspectives 322
References 323
11 Cholesterol in NiemannPick Type C disease 336
11.1 Introduction 336
11.2 NPC Proteins and Intracellular Cholesterol Transport 337
11.3 Cholesterol Accumulation in Niemann-Pick Type C Disease 338
11.4 Suppression of Brain Cholesterol Synthesis in NPC Disease 340
11.5 Impairment of Cholesterol Transport in NPC Disease 341
11.6 Cholesterol Accumulation-Associated Autophagy in NPC Disease 342
11.7 Treatment Development for NPC Disease 344
11.8 Conclusions 345
References 345
12 Protein Mediators of Sterol Transport Across Intestinal Brush Border Membrane 353
12.1 Introduction 354
12.2 Intestinal Cholesterol Absorption and Ezetimibe 354
12.3 NPC1L1 356
12.3.1 Structure: Gene, mRNA, and Protein Domains 356
12.3.2 Function: Lessons Learned from Animal Models and Human Genetics 358
12.3.3 Function: Lessons Learned from Cell Model Systems 359
12.3.4 Regulation of Expression 361
12.3.5 Cholesterol and Ezetimibe Binding Studies 363
12.3.6 Potential Mechanisms for NPC1L1 to Mediate Sterol Uptake 364
12.3.7 Therapeutic Perspectives 365
12.4 ATP-Binding Cassette Transporters G5 and G8 (ABCG5/G8) 366
12.4.1 Discovery of ABCG5/G8: The Power of Human Genetics 366
12.4.2 Structure: Gene, mRNA, and Protein Domains 366
12.4.3 Function: Lessons Learned from Animal Models 367
12.4.4 Function: Lessons Learned from Cell Model Systems 368
12.4.5 Regulation of Expression 369
12.4.6 Biochemical Studies on ABCG5/G8-dependent Sterol Transport 370
12.4.7 Therapeutic Perspectives for ABCG5/G8 370
12.5 Scavenger Receptor Class B Type l (SR-Bl) 372
12.5.1 Discovery of SR-BI 372
12.5.2 Structure: Gene, mRNA, and Protein Domains 372
12.5.3 Function: Lessons Learned from Animal Models 373
12.5.4 Function: Lessons Learned from Cell Model Systems 374
12.5.5 Regulation of Expression 375
12.5.6 Cholesterol Binding Studies 377
12.5.7 Therapeutic Perspectives for SR-BI 377
12.6 Other Proteins Influencing Intestinal Cholesterol Absorption 378
12.7 Concluding Comments 379
References 379
13 Cholesterol at the Endoplasmic Reticulum: Roles of the Sigma-1 Receptor Chaperone and Implications thereof in Human Diseases 397
13.1 Introduction 398
13.2 Structure and Subcellular Localization of the Sigma-1 Receptor 399
13.3 The Potential Link Between the Sigma-1 Receptor and Sterols 402
13.4 Sigma-1 Receptors Interact with Cholesterol 403
13.5 Molecular Function of the Sigma-1 Receptor 405
13.6 Ligand-Binding Profile of the Sigma-1 Receptor 406
13.7 Roles of Sigma-1 Receptors in Subcellular Distribution of Lipids and Reconstitution of Lipid Rafts 407
13.8 The Sigma-1 Receptor in Human Diseases 408
13.8.1 Neuropsychiatric Disorders 408
13.8.2 Cancer 409
13.9 Conclusions 409
References 410
14 Prominin-1: A Distinct Cholesterol-Binding Membrane Protein and the Organisation of the Apical Plasma Membrane of Epithelial Cells 415
14.1 Introduction 415
14.2 Prominin Molecules and Plasma Membrane Protrusions 417
14.2.1 Prominin -- Basic Facts 417
14.2.2 Prominin-1 and Photoreceptors 419
14.3 The Apical Plasma Membrane Contains Distinct Cholesterol-Based Membrane Microdomains 420
14.3.1 Prominin-1 -- A Cholesterol-Interacting Protein Associated with a Distinct Membrane Microdomain Subtype 420
14.3.2 Distinct Cholesterol-Based Membrane Microdomain Subtypes as Building Units of the Apical Plasma Membrane 423
14.3.3 Distinct Ganglioside-Associated Membrane Microdomain Within the Apical Plasma Membrane 425
14.3.4 How Are Prominins Incorporated into the Protrusion-Specific Subtype of Membrane Microdomains? -- Facts and Hypotheses 426
14.4 Dynamics of Apical Plasma Membrane Protrusions 427
14.4.1 Prominin-Containing Extracellular Membrane Vesicles 427
14.4.2 Role of Membrane Microdomains in the Release of Small Extracellular Membrane Vesicles 428
14.5 Perspectives 431
References 432
15 Mammalian StAR-Related Lipid Transfer (START) Domains with Specificity for Cholesterol: Structural Conservation and Mechanism of Reversible Binding 440
15.1 Introduction 440
15.2 The START Domains That Specifically Bind Cholesterol Have a Highly Conserved / Helix Grip Fold 443
15.3 To Be or Not to Be a Molten Globule to Bind and Release Cholesterol Reversibly? 444
15.4 Experimental Validation of the Two-State Model 445
15.5 Towards a Consensual Model for the Reversible and Specific Binding of Cholesterol by START Domain 449
15.6 Conclusions and Perspectives 450
References 450
16 Membrane Cholesterol in the Function and Organization of G-Protein Coupled Receptors 453
16.1 Introduction 454
16.2 Cholesterol in Biological Membranes: A Tale of Two Faces 455
16.3 Role of Membrane Cholesterol in the Function of G-Protein Coupled Receptors 457
16.3.1 Effect of Membrane Cholesterol on the Function of GPCRs: General Effect or Specific Interaction ? 458
16.3.1.1 Rhodopsin 459
16.3.1.2 Oxytocin and Cholecystokinin Receptors 460
16.3.1.3 Galanin Receptors 461
16.4 Nonannular Lipids in the Function of Membrane Proteins 461
16.4.1 Presence of Specific (Nonannular?) Cholesterol binding Sites in the Crystal Structures of GPCRs 463
16.4.1.1 Rhodopsin 463
16.4.1.2 0 ß2-Adrenergic Receptor 463
16.5 The Serotonin 1A Receptor: A Representative Member of the GPCR Superfamily in the Context of Membrane Cholesterol Dependence for Receptor Function 466
16.5.1 Cholesterol binding Motif(s) in Serotonin 1A Receptors? 471
16.6 Conclusion and Future Perspectives 471
References 473
17 Cholesterol Effects on Nicotinic Acetylcholine Receptor: Cellular Aspects 481
17.1 Introduction 482
17.2 The Natural Scenario of AChR-Cholesterol Interactions 483
17.3 Lipid-AChR Interactions at the Cellular Scale. Tentative Association of AChR Clusters with a Specific Subset of Lipid Domains, the Lipid Rafts 484
17.4 Cholesterol Sensitivity of AChR Exocytic Trafficking 486
17.5 Cholesterol Sensitivity of AChR Endocytosis 486
17.6 Diffuse AChRs Are in Fact Organized in the Form of Nanoclusters at the Cell Surface 491
17.7 How Do Cholesterol Levels Modulate AChR Stability at the Cell Membrane? 493
17.8 Possible Relationship Between AChR Nanocluster Organization and the Membrane-Associated Cortical Cytoskeletal Network 494
17.9 A Word on Cholesterol Binding Sites 496
References 497
18 Cholesterol and Myelin Biogenesis 502
18.1 Introduction 502
18.2 Myelin Structure and Composition 503
18.3 Schwann Cells 504
18.3.1 The Origin and Differentiation of Schwann Cells 505
18.3.2 Origin and Differentiation of Oligodendrocytes 507
18.4 Source of Cholesterol in Myelin 508
18.5 Cholesterol-Binding Proteins in Myelin 510
18.6 Cholesterol Depletion in Oligodendrocytes and Schwann cells In Vivo 512
18.7 Conclusions 516
References 517
19 Cholesterol and Ion Channels 522
19.1 Introduction 522
19.2 Cholesterol Regulation of K+ Channels 525
19.2.1 Inwardly Rectifying K+ (Kir) Channels 525
19.2.2 Kir2 Channels 526
19.2.3 Kir3 Channels 528
19.2.4 Kir4 Channels 529
19.2.5 Kir6 (K ATP) Channels 529
19.3 Association of Kir Channels with Cholesterol-Rich Membrane Domains (Lipid Rafts) 529
19.3.1 Regulation of Kir Channels by Plasma Hypercholesterolemia In Vivo 530
19.4 Voltage-Gated K+ (Kv) Channels 531
19.4.1 Kv1 Channels 532
19.4.2 Kv2 Channels 533
19.4.3 Other Kv Channels 533
19.4.4 Regulation of Kv Channels by Plasma Hypercholesterolemia 534
19.5 Ca2+ -Activated K+ Channels 534
19.5.1 BK 536
19.5.2 SK and IK 537
19.6 Na+ Channels 538
19.6.1 Voltage-Gated Na+ (Nav) Channels 538
19.6.2 Epithelial Na+ Channels (eNaC) 540
19.7 Ca+ Channels 540
19.7.1 Voltage-Gated Ca+ 2 (Cav) Channels 541
19.7.2 L-Type Ca2+ Channels 541
19.7.3 N-Type Ca2+ Channels 542
19.8 Transient Receptor Potential (TRP) Channels 542
19.8.1 TRPV Channels 543
19.8.2 TRPC Channels 543
19.9 TRPM Channels 545
19.10 Cl- Channels 545
19.10.1 Voltage-Gated Cl- Channels 546
19.10.2 CFTR 547
19.11 Volume-Regulated Anion Channel (VRAC) 547
19.12 Mechanosensitive Channels 548
19.13 Concluding Remarks and Future Directions 550
References 551
20 The Cholesterol-Dependent Cytolysin Family of Gram-Positive Bacterial Toxins 563
20.1 Introduction 564
20.2 Mechanism of Pore Formation 564
20.2.1 Localizing the Target Membrane 569
20.2.2 Grouping Forces on the Membrane Surface: Pre-pore Formation 569
20.2.3 Perforating the Membrane: Insertion of a Large ß-Barrel 572
20.3 The Role of Cholesterol in Membrane Binding 573
20.3.1 Domain 4 and Membrane Recognition 573
20.3.1.1 The Conserved Loops 574
20.3.2 Searching for Cholesterol in the Membrane 576
20.3.2.1 Cholesterol Availability in Membrane Bilayers 577
20.3.2.2 The Role of Other Lipids 578
20.3.2.3 Cholesterol Alone Is Enough 580
20.4 Conclusions and Future Perspectives 581
References 583
21 Cholesterol Specificity of Some Heptameric -Barrel Pore-Forming Bacterial Toxins: Structural and Functional Aspects 590
21.1 Introduction 590
21.2 Vibrio cholerae Cytolysin (VCC) 591
21.2.1 Structure of the VCC Oligomer 592
21.2.2 Fibril Formation by VCC and Other Toxins In Vitro 598
21.3 Hemolysins/Cytolysins from Other Vibrio Species 599
21.4 Cholesterol Dependency of Heptameric and Other -Barrel-Forming Hemolysins/Toxins from Non- Vibrio Species 600
21.5 Conclusions 602
References 603
22 Cholesterol-Binding Toxins and Anti-cholesterol Antibodies as Structural Probes for Cholesterol Localization 608
22.1 Introduction 609
22.2 Cholesterol-Binding Toxins 609
22.2.1 Preparation of Non-cytolytic Derivatives of Perfringolysin O 610
22.2.2 Binding Properties of Perfringolysin O Derivatives 612
22.2.2.1 Specific Binding to Cholesterol 612
22.2.2.2 Selective Binding to Cholesterol-Enriched Membranes 614
22.2.3 Application of Perfringolysin O Derivatives to the Detection of Cholesterol-Rich Membranes 617
22.2.3.1 BC as a Marker of Cholesterol-Rich Microdomains on the Cell Surface 618
22.2.3.2 Detection of Cholesterol-Rich Microdomains in the Inner Leaflet of the Plasma Membrane 619
22.2.3.3 Electron Microscopic Analysis of Microdomains in Intracellular Membranes 620
22.2.3.4 Microdomains in T-cell Receptor Signalling 621
22.2.3.5 Microdomains in Cholesterol Storage/Transport Disorders 622
22.3 Anti-cholesterol Antibodies 624
22.3.1 Characterization and Binding Properties 624
22.3.2 Application to Cellular Cholesterol Detection 625
22.4 Conclusions 626
References 626
Index 633

Produkt-Details

• Erscheint lt. Verlag: 10.3.2010
• Reihe/Serie: Subcellular Biochemistry
• Reihe/Serie: Subcellular Biochemistry
• Zusatzinfo: XXII, 632 p.
• Verlagsort: Dordrecht
• Sprache: englisch
• Themenwelt: Studium ► 1. Studienabschnitt (Vorklinik) ► Biochemie / Molekularbiologie
• Themenwelt: Naturwissenschaften ► Biologie ► Biochemie
• Themenwelt: Naturwissenschaften ► Biologie ► Zellbiologie
• Themenwelt: Naturwissenschaften ► Biologie ► Zoologie
• Themenwelt: Technik
• Schlagworte: Apoptosis • Chaperone • conservation • Lipid • Mammalia • proteins • Protein Structure
• ISBN-10: 90-481-8622-6 / 9048186226
• ISBN-13: 978-90-481-8622-8 / 9789048186228