Brassinosteroids: A Class of Plant Hormone (eBook)

Contents 8
Foreword 10
Preface 12
Contributors 14
About the Editors 20
Chapter 1:BRASSINOSTEROIDS – OCCURENCEAND CHEMICAL STRUCTURES IN PLANTS 22
1. INTRODUCTION 22
2. OCCURENCE OF BRASSINOSTEROIDS 23
3. CHEMICAL STRUCTURE OF BRASSINOSTEROIDS 34
4. REFERENCES 42
Chapter 2:REGULATORY MECHANISMS OF BRASSINOSTEROID SIGNALING IN PLANTS 49
1. INTRODUCTION 49
2. THE BR SIGNALING PATHWAY 50
3. UPSTREAM MECHANISMS OF THE BR SIGNALING REGULATION 52
3.1 BR receptors and ligand binding 52
3.2 Activation of BRI1 by phosphorylation 53
3.3 The function of BRI1 co-receptors 54
3.4 Other plasma membrane-associated BR signaling components 55
4. REGULATION OF BR SIGNALING BY DOWNSTREAM COMPONENTS 56
4.1 The function of the GSK3/shaggy-like kinases in BR signaling 56
4.2 Mechanisms of BIN2 regulation 58
4.3 Regulation of downstream BR signaling by BZR1 and BES1/BZR2 transcription factors 59
4.4 Regulation of downstream BR signaling by atypical bHLH proteins 61
5. ENDOMEMBRANE TRAFFICKING REGULATES THE BR SIGNALING 62
5.1 The endocytosis of BRI1 is ligand independent and BFA sensitive 62
5.2 BRI1 signals from endosomal compartments 63
5.3 The function of endoplasmic reticulum (ER) quality control (ERQC) in BR signaling 64
6. CONSERVATION OF BR SIGNALING MECHANISMS IN PLANTS 65
6.1 Conservation in upstream BR signaling components 65
6.2 Conservation in downstream BR signaling components 67
7. CONCLUSION 68
8. ACKNOWLEDGEMENTS 68
9. REFERENCES 69
Chapter 3:REGULATION OF BRASSINOSTEROID METABOLISM 77
1. INTRODUCTION 77
2. BR BIOSYNTHESIS 78
2.1 Organ- and tissue-specific regulation 80
2.2 Developmental regulation 82
2.3 Hormonal regulation 84
2.4 Diurnal regulation 86
2.5 Functional aspects of BR synthesis 87
3. BR INACTIVATION 89
3.1 Organ- and tissue-specific regulation 90
3.2 Developmental regulation 91
3.3 Hormonal regulation 92
3.4 Diurnal regulation 92
4. COORDINATION OF BIOSYNTHETIC AND INACTIVATING FUNCTIONS 93
5. CONCLUDING REMARKS 94
6. ACKNOWLEDGEMENTS 96
Chapter 4:BRASSINOSTEROID SIGNALING IN RICE 102
1. INTRODUCTION: UTILITY OF RICE FOR BR SIGNALING STUDIES 102
2. OsBRI1 PATHWAY AND OTHER SIGNALING FACTORS 105
3. OsBRI1 PATHWAY 107
3.1 OsBRI1 107
3.1.1 OsBRI1 107
3.1.2 Mutant alleles of OsBRI1 109
3.1.3 d61-4, a putative null mutant of OsBRI1 109
3.1.4 Agronomic use of d61-7, the weakest allele of OsBRI1, and OsBRI1 knock-down plants 110
3.2 OsBRL1 and OsBRL3 111
3.3 OsBAK1 112
3.4 OsGSK1 (A BIN2-orthologue) 113
3.4.1 OsGSK1 114
3.4.2 Developmental role of OsGSK1 114
3.4.3 Role of OsGSK1 in abiotic stresses tolerance 115
3.4.4 Role of OsGSK1 in BR signaling 115
3.5 OsBZR1 and 14-3-3 116
3.5.1 OsBZR1 117
3.5.2 14-3-3 proteins: OsBZR1-interacting proteins 118
3.6 DLT 119
4. OTHER BR SIGNALING FACTORS IN RICE 119
4.1 RGA1 120
4.1.1 RGA1 121
4.1.2 Structure and mutation alleles of RGA1 121
4.1.3 Constitutive active forms of RGA1 122
4.1.4 Role of RGA1 in BR signaling 122
4.1.5 Interaction between RGA1 and OsBRI1 pathway 123
4.1.6 RGA1 is not involved in feedback regulation of BR biosynthesis 124
4.1.7 RGA1 functions in other regulation, GA, etc. 125
4.1.8 Relationship between OsBRI1 pathway, RGA1 and other signaling factors 125
5. BR RESPONSIVE HELIX LOOP HELIX (HLH) PROTEINS 126
5.1 BU1 126
5.2 ILI1 and IBH1 131
5.2.1 ILI1 131
5.2.2 IBH1 131
6. CONCLUSION 132
7. ACKNOWLEDGEMENT 132
8. REFERENCES 132
Chapter 5:BRASSINOSTEROIDS AND LIGHT – REGULATORY FACTORS OF GROWTH AND DEVELOPMENT OF PLANTS 137
1. INTRODUCTION 137
2. THE PHYSIOLOGICAL ACTION OF BRASSINOSTEROIDS DEPENDS ON THEIR CONCENTRATION IN A PLANT AND THE MEDIUM 140
2.1 The BRs role in regulating the scotomorphogenesis of Arabidopsis thaliana seedlings 140
2.2 Interaction of 24-epibrassinolide and gibberellic acid in the regulation of Arabidopsis thaliana seedlings scotomorphogenesis 141
2.3 Interaction of 24-epibrassinolide and ecdysterone in the regulation of elongation of wheat coleoptiles 142
3. THE PHYSIOLOGICAL ACTION OF BRASSINOSTEROIDS DEPENDS ON THE METHOD OF TREATMENT OF THE EXOGENOUS HORMONE 143
4. THE PHYSIOLOGICAL ACTION OF BRASSINOSTEROIDS DEPENDS ON LIGHTOF DIFFERENT SPECTRAL COMPOSITI ON 145
5. THE MECHANISM OF REGULATION OF PHOTOMORPHOGENESIS BY BRASSINOSTEROIDS 150
6. CONCLUSION 153
7. ACKNOWLEDGEMENT 153
8. REFERENCES 153
Chapter 6:BRASSINOSTEROIDS AND PHOTOSYNTHESIS 160
1. INTRODUCTION 161
2. EXOGENOUSLY APPLIED BRASSINOSTEROIDS AFFECT PHOTOSYNTHESIS AT VARIOUS LEVELS 162
2.1 Net photosynthetic rate 163
2.2 Stomatal function 185
2.3 Enzymes of photosynthetic carbon reduction cycle 186
2.4 Photosynthetic pigments and light-harvesting 189
2.5 Primary photochemistry 192
2.6 Chloroplast ultrastructure 194
3. STRESS FACTORS ENHANCE THE EFFECT OF BRASSINOSTEROIDS ON PHOTOSYNTHESIS 194
4. PHOTOSYNTHESIS IN BRASSINOSTEROIDSDEFICIENT MUTANTS OR TRANSGENIC PLANTS 197
5. THE AGE OF “OMICS”: WHAT DID WE LEARN FROM LARGE-SCALE ANALYSES? 199
6. CONCLUSIONS AND FUTURE CHALLENGES 201
7. ACKNOWLEDGEMENT 202
8. REFERENCES 202
Chapter 7:PHYSIOLOGICAL EFFECTS RELATEDTO BRASSINOSTEROID APPLICATION IN PLANTS 210
1. INTRODUCTION 211
2. BRASSINOSTEROID APPLICATION TRIGGERSSEVERAL RESPONSES RELATED TO PLANT GROWTH AND DEVELOPMENT 212
2.1 Brassinosteroid interactions with other plant growth substances 219
2.2 Does exogenous BR change the endogenous concentration of other plant hormones? 221
2.3 Seed germination is enhanced by exogenous brassinosteroids 222
2.4 How exogenous BR application may regulate flowering and fructification? 225
2.5 Senescence is also a process regulated by brassinosteroid 227
3. BRASSINOSTEROID-APPLIED AMELIORATIVE EFFECTS TO A WIDE RANGE OF PLANT STRESS 229
3.1 Disease stress 229
3.2 Water Stress 231
3.3 Saline Stress 233
3.4 Thermal Stress 238
3.1.1 Heat Stress 239
3.1.2 Cold Stress 240
3.5 Pesticide stress 241
3.6 Heavy metals stress 243
3.7 Hypoxia Stress 247
5. CONCLUSION 252
6. ACKNOWLEDGEMENTS 253
Chapter 8:GENOMIC AND NON-GENOMIC EVENTS INVOLVED IN THE BRASSINOSTEROID-PROMOTED PLANT CELL GROWTH 260
1. INTRODUCTION 260
2. CONTROL OF CELL EXPANSION 261
3. THE ROLE OF CELL WALL ENZYMES IN THE BRASSIONOSTEROIDS-PROMOTED CELL EXPANSION 264
4. THE ROLE OF VACUOLAR H+ -ATPASE IN THE CONTROL OF CELL EXPANSION BY BRASSIONOSTEROIDS 266
5. THE ROLE OF MICROTUBES IN THE CONTROL OF CELL EXPANSIONBY BRASSIONOSTEROIDS 267
6. THE ROLE OF AQUAPORINS IN THE CONTROL OF CELL EXPANSION BY BRASSINOSTEROIDS 270
7. CONTROLL OF CELL DIVISION BY BRASSIONOSTEROIDS 271
8. CONTROL OF CELL WEIGHT ACCUMULATION BY BRASSINOSTEROIDS 276
9. CONTROL OF CELL EXPANSION BY INHIBITORS OF BR BIOSYNTHESIS 276
10. CONTROL OF CELL WEIGHT BY INHIBITORS OF BR BIOSYNTHESIS 277
11. CONCLUSION 277
12. ACKNOWLEDGEMENTS 278
13. REFERENCES 278
Chapter 9:ROLE OF BRASSINOSTEROIDS ON HORTICULTURAL CROPS 286
1. INTRODUCTION 286
2. SEED DEVELOPMENT AND GERMINATION 288
3. BRs AND PLANT GROWTH 288
3.1 Vegetative growth 289
3.1.1 Shoot 289
3.1.2 Root 290
3.2 Reproductive growth 291
3.2.1 Flowers 291
3.2.2 Fruits 292
3.2.3 Seeds 293
3.3 Micropropagation 293
4. BRs AND STRESS RESPONSES 294
4.1 Oxidative stress 295
4.2 Heavy metals stress 295
4.3 Thermal stress 296
4.4 Water stress 297
4.5 Hypoxia stress 298
4.6 Pathogen stress 298
4.7 Pesticides application 299
5. CONCLUSION 300
6. ACKNOWLEDGEMENT 300
7. REFERENCES 301
Chapter 10:BRASSINOSTEROID ACTION AND ITS RELATION WITH HEAT STRESS MECHANISMS IN PLANTS 306
1. INTRODUCTION 307
2. BR INDUCE HEAT STRESS TOLERANCE IN PLANTS 307
2.1 BR-induced heat tolerance in the reproductive development 310
2.2 Induction of heat tolerance by spirostanic analogues of BRs 311
2.3 Heat tolerance of mutants with altered BR signaling 311
2.4 Interactions of BRs with other hormones in plant heat tolerance 312
3. INVOLVEMENT OF HEAT SHOCK PROTEINS IN BR-MEDIATED EFFECTS 313
3.1 HSP101 314
3.2 HSP90 314
3.3 HSP70 314
3.4 sHSPs 315
4. OXIDANTS AND ANTIOXIDANTS IN BR-MEDIATED HEAT STRESS EFFECTS 317
4.1 Relationship between HSP/oxidative responses and BR signaling 318
5. CONCLUSION 320
6. ACKNOWLEDGEMENT 321
7. REFERENCES 321
Chapter 11:PROTECTIVE EFFECTS OF BRASSINOSTEROIDS AGAINST HERBICIDES 325
1. INTRODUCTION 326
2. PHOTOSYNTHESIS-INHIBITOR HERBICIDES 326
3. CHLOROPHYLL FLUORESCENCE AS AN INDICATOR OF THE HERBICIDES EFFECT IN THE PHOTOSYNTHETIC APPARATUS 329
4. EFFECT OF BRASSINOSTEROIDS ON CROP PLANTS TREATED WITH PHOTOSYNTHESISINHIBITING HERBICIDES 330
4.1 Effect on crop plants treated with photosynthesisinhibiting herbicides at the level of PS II 330
4.2 Effect on crop plants treated with photosynthesisinhibiting herbicides at the level of PS I 331
5. NEW DATA ON THE EFFECT OF 24-EPIBRASSINOLIDE ON PLANTS TREATED WITH HERBICIDES THAT INHIBIT ELECTRONTRANSPORT AT THE PS II LEVEL 332
5.1 Effect of EBR on Vicia faba plants treated with cyanazine, an s-triazine herbicide 332
5.2 Effect of EBR on Vicia faba plants treated with simazine, an s-triazine herbicide 339
5.3 Effect of EBR on Vicia faba plants treated with methabenzthiazuron, a urea derivative herbicide 347
5.4 Effect of EBR on Vicia faba plants treated with metribuzin, an as-triazinone herbicide 348
6. COMPARATIVE EFFECTS OF 24-EPIBRASSINOLIDE AND PHOTOSYNTHESISINHIBITOR HERBICIDES AT THE PS II LEVEL 349
7. HOW DO BRASSINOSTEROIDS ALLEVIATE THE DAMAGE EFFECT CAUSED BY HERBICIDES? 352
8. CONCLUSION 354
9. ACKNOWLEDGEMENT 355
10. REFERENCES 355
Chapter 12:BRASSINOSTEROIDS: UNDER BIOTIC STRESS 361
1. INTRODUCTION 361
2. ROLE OF BRs UNDER BIOTIC STRESS 363
3. PLANT REGULATION STRATEGY AGAINST BIOTIC STRESS 364
4. BRs AND ANTIOXIDANT SYSTEM STATUS UNDER BIOTIC STRESS 365
5. INTERACTION OF BRs WITH OTHERP HYTOHORMONES UNDER BIOTIC STRESS 366
5.1 The interaction of classical phytohormones with BRs 366
5.2 BRs interaction with highly active molecules 368
6. BRs, SIGNAL PERCEPTION AND ITS TRANSDUCTION 369
7. CONCLUSIONS AND FUTURE PROSPECTS 372
8. REFERENCES 372
Chapter 13:THE SIGNIFICANCE OF ETHANOL AS A HORMONE SOLVENT IN EXPERIMENTS ON THE PHYSIOLOGICAL ACTIVITY OF BRASSINOSTEROIDS 377
1. INTRODUCTION 378
2. ETHANOL IN PLANTS 378
2.1 Occurrence of endogenous ethanol in plants 378
2.2 Metabolism of exogenous ethanol in plants 379
2.3 Physiological activity of ethanol in plants 379
3. THE EFFECT OF METHANOL AND DMSO ON PLANTS 380
4. ETHANOL IN EXPERIMENTS WITH BRASSINOSTEROIDS 382
4.1 Effect of 24-epibrassinolide and ethanol on brassinosteroids content in grains of spring wheat 382
4.2 Effect of 24-epibrassinolide and ethanol on qualitative composition of spring wheat grains 383
4.3 Effect of 24-epibrassinolide and ethanol on permeability of cell membranes 384
4.4 Effect of 24-epibrassinolide and ethanol on the content of pigments 385
4.5 Effect of 24-epibrassinolide and ethanol on spring barley heading 386
5. CONCLUSION 388
6. REFERENCES 388
Chapter 14:IMMUNOASSAYS OF BRASSINOSTEROIDS 391
1. INTRODUCTION 391
2. IMMUNOGEN PREPARATION 393
2.1 O-(Carboxymethyl)oxime haptens linked in the C-6 position 393
2.2 Haptens linked through hydroxy groups 395
3. ANTIGEN LABELING 399
4. BINDING PROPERTIES OF ANTIBODIES 405
5. ACKNOWLEDGEMENT 406
6. REFERENCES 406
Chapter 15:TRANSCRIPTOMICS AND PROTEOMICS STUDY IN REGULATION OF BRASSINOSTEROIDS 409
1. INTRODUCTION 410
2. TRANSCRIPTOMICS STUDY IN BR REGULATION 411
3. PROTEOMICS STUDY IN BR REGULATION 412
4. CLUSTERING FOR ELUCIDATING REGULATION OF BRS 413
5. GENE NETWORK FOR REGULATION OF BRs 414
5.1 Inferring gene network 415
5.2 Significant functional networks and biological pathway annotations 415
6. CONCLUSIONS 415
7. ACKNOWLEDGMENTS 416
8. REFERENCES 416
Chapter 16:BRASSINOSTEROIDS FOR PHYTOREMEDIATION APPLICATION 419
1. INTRODUCTION 420
2. PHYTOREMEDIATION TECHNOLOGIES: PROCESSES AND PHYSIOLOGICAL MECHANISMS 421
2.1 Phytoremediation technologies for organic contaminants 422
2.1.1 Rhizodegradation 423
2.1.2 Phytodegradation 423
2.1.3 Phytovolatilization 424
2.2 Mechanisms associated with the phytoremediation of organic contaminants 425
2.3 Phytoremediation technologies for inorganic contaminants 426
2.3.1 Phytoextraction or phytoaccumulation 427
2.3.2 Phytostabilization 428
2.3.3 Rhizofiltration or phytofiltration 429
2.3.4 Phytohydraulic or hydraulic control 429
2.4 Mechanisms associated with the phytoremediation of inorganic contaminants 430
3. BRASSINOSTEROIDS AND THEIR POSSIBLE ROLE IN PHYTOREMEDIATION MECHANISMS 434
3.1 Potential of phytohormone application in phytoremediation 434
3.2 Brassinosteroids for phytoremediation: potential application 437
3.3 Brassinosteroids increase germination 438
3.4 Brassinosteroids increase plant yield 439
3.5 Brassinosteroids increase environmental stress tolerance 440
3.6 Brassinosteroids and inorganic contaminant action 441
3.7 Brassinosteroids and organic contaminant action 442
3.8 Applying Brassinosteroids in the field 443
4. CONCLUSION AND FUTURE DIRECTIONS 445
5. REFERENCES 446
Chapter 17:PROSPECTS OF BRASSINOSTEROIDS IN MEDICINAL APPLICATIONS 454
1. INTRODUCTION 455
1.1 Brassinosteroids and abiotic stress 456
1.2 Brassinosteroids and biotic stress 457
2. BIOLOGICAL ACTIVITIES OF BRASSINOSTEROIDS IN VARIOUS TEST SYSTEMS 458
2.1 Ecdysteroidal activity of brassinosteroids 458
2.2 Antifungal activity of brassinosteroids 459
2.3 Antigenotoxic activity of brassinosteroids 460
2.4 Antiviral and antibacterial activities of brassinosteroids 461
2.5 Antiproliferative and anticancer activities of brassinosteroid 465
2.6 Brassinosteroids and cotton leafworm Spodoptera littoralis G. 467
2.7 Brassinosteroids and insects 467
3. NEUROACTIVITIES 468
4. CONCLUSIONS 468
5. REFERENCES 468
Index 474