Author(s): Susheng Gan
Edition: 1
Year: 2007
Language: English
Pages: 352
Senescence Processes in Plants......Page 1
Contents......Page 7
Contributors......Page 17
Preface......Page 19
1.2 Terminology and types of senescence......Page 23
1.3 Plants exhibit mitotic senescence, postmitotic senescence and cell quiescence......Page 25
1.4.2 Maintenance of SAM......Page 26
1.4.3.1 Physiological regulation......Page 27
1.5.2 Telomerase......Page 29
1.5.4 Telomere biology in plants......Page 30
1.6 Closing remarks......Page 31
References......Page 32
2.2.1.1 Chlorins......Page 34
2.2.2.1 Red chlorophyll catabolites......Page 37
2.2.2.3 Nonfluorescent chlorophyll catabolites......Page 38
2.2.2.4 Are NCCs degraded further?......Page 39
2.3.2.1 Chlorophyllase......Page 40
2.3.2.2 Mg dechelation......Page 41
2.3.3.1 Pheophorbide a oxygenase......Page 42
2.3.4.1 Hydroxylation......Page 43
2.3.4.5 Tautomerization......Page 44
2.5.1 Topology of chlorophyll breakdown......Page 45
2.5.2 Chl breakdown and cell death......Page 46
2.5.3 Chl breakdown and nitrogen economy......Page 47
2.6 The pigments of senescing leaves......Page 48
2.7.1 Physiological explanations......Page 50
2.7.2 Ecological explanations......Page 51
2.8 Conclusions and perspectives......Page 52
References......Page 53
3.1 Introduction......Page 61
3.2.1 Senescence-associated changes in the molecular organization of membrane lipid bilayers......Page 62
3.2.2 Role of lipases......Page 64
3.2.2.1 Initial fate of de-esterified fatty acids in senescing membranes......Page 65
3.2.2.2 Autocatalytic nature of membrane fatty acid de-esterification......Page 66
3.2.3 Role of galactolipases......Page 67
3.3 Role of proteolysis in membrane senescence......Page 70
3.4.1 Plastoglobuli......Page 73
3.4.2.1 Sites of cytosolic lipid-protein particle ontogeny......Page 76
3.5 Role of autophagy......Page 77
3.6 Metabolism of membrane fatty acids in senescing tissues......Page 79
3.6.1 Galactolipid fatty acids......Page 80
3.6.2 Fate of thylakoid fatty acids during stress-induced senescence......Page 81
3.7 Translational regulation of senescence......Page 83
References......Page 84
4.1 Introduction......Page 91
4.2 Antioxidative capacity, oxidative stress and life span......Page 93
4.3 Antioxidants......Page 94
4.4 ROS signaling......Page 96
4.5.1 Peroxisomes......Page 99
4.5.2 Chloroplasts......Page 100
4.5.3 Mitochondria......Page 101
4.5.4 Nucleus......Page 102
References......Page 103
5.1 Overview......Page 109
5.2 Macro- and micronutrient remobilization......Page 110
5.2.1 Carbon......Page 111
5.2.3 Phosphorus......Page 112
5.2.5 Magnesium, calcium and micronutrients......Page 113
5.3 Nitrogen remobilization......Page 114
5.3.1.1 Classification of peptidases......Page 115
5.3.1.2 Compartmentation of peptidases......Page 116
5.3.1.3 Regulation of peptidases during leaf senescence......Page 118
5.3.2 Amino acid metabolism in senescing leaves......Page 120
5.3.3 Nitrogen transport to developing sinks......Page 121
5.4 Outlook......Page 123
References......Page 124
6.1 Introduction......Page 130
6.2.1.1 Low light......Page 133
6.2.1.2 Darkness......Page 134
6.2.1.3 High light......Page 135
6.2.3.1 Red/Far red......Page 136
6.2.3.3 Ultraviolet......Page 138
6.3 Ozone......Page 140
6.4 Temperature......Page 141
6.5 Drought stress......Page 142
6.6 Flooding......Page 143
6.7 Salinity......Page 144
6.8 Environmental pollution – toxic materials......Page 145
6.9 Oxidative stress involvement in environmental regulation of senescence......Page 146
6.10 Nutrient/mineral shortage......Page 147
6.11 Atmospheric CO2......Page 148
6.12 Biotic stress......Page 149
6.13 Concluding remarks......Page 152
References......Page 155
7.2 Developmental senescence: a plant genome is optimised for early survival and reproduction......Page 167
7.3.1 Reactive oxygen species......Page 169
7.3.3 Protein degradation......Page 170
7.4 Hormonal control of leaf senescence......Page 171
7.4.1.2 Auxin......Page 172
7.4.1.3 Cytokinins......Page 173
7.4.2.1 ABA......Page 174
7.4.2.2 Brassinosteroids......Page 175
7.4.2.3 Ethylene......Page 176
7.4.2.4 Jasmonic acid......Page 178
7.5 Involvement of genome programmes in the regulation of senescence-associated genes......Page 179
7.6 Integrating hormonal action into developmental senescence......Page 183
7.7 Outlook and perspectives......Page 185
References......Page 186
8.1.3 QTL mapping......Page 193
8.1.4 ‘QTL for’ talk......Page 195
8.2.3 Pseudosenescence......Page 196
8.3.2 Allometry and QTL......Page 197
8.4.3 Implications for the design and conduct of QTL experiments......Page 199
8.5.1 Rice......Page 200
8.5.2 Sorghum and millet......Page 203
8.5.3 Maize......Page 206
8.5.4 Wheat and barley......Page 208
8.5.5 Other species......Page 210
8.6.1 Model species, comparative mapping and the role of bioinformatics......Page 211
8.6.2 Introgression landing......Page 214
8.6.3 Integration with omics and other technologies......Page 215
8.6.4 QTL as breeding tools......Page 216
References......Page 217
9.1 Introduction......Page 224
9.2.1.1 Differential display, in situ hybridization and subtractive hybridization......Page 225
9.2.1.2 Microarrays......Page 226
9.2.2 Altering the expression of senescence-specific genes may extend the lifespan of annual plants......Page 227
9.2.3 From single to global gene expression studies of leaf senescence......Page 228
9.2.4 Kinetics studies of gene expression define sequential changes in the pathway of the senescence program......Page 229
9.2.5 Classification of the SAGs into functional classes suggests potential regulatory and biochemical pathways occurring during senescence......Page 231
9.2.6 Stress-induced and developmental senescence can be compared by genomic studies......Page 233
9.2.7 Signaling pathways of the senescence program can be elucidated by global gene expression studies......Page 235
9.2.8 Global gene expression studies reveal that autumn leaf senescence has much in common with the senescence in annual plants......Page 237
9.3.1.1 Two-dimensional gel electrophoresis......Page 238
9.3.1.3 Mass spectrometry......Page 239
9.3.2 Current information on leaf senescence proteomic is limited......Page 241
9.3.4 Senescence upregulated proteins involved in respiration and various associated metabolic processes......Page 245
9.3.5 Degradation and transport processes......Page 246
9.3.7 Comparison between pattern of changes in mRNA and protein levels during senescence indicates partial correlation......Page 247
References......Page 249
10.1.2 Senescence-associated genes......Page 253
10.2.1 Isolation of SAGs......Page 254
10.2.2.1 Macromolecule degradation......Page 255
10.2.2.4 Regulatory genes......Page 256
10.2.3 Comparison of SAGs in various plant species......Page 258
10.3 Regulatory modes of SAGs......Page 259
10.3.1 Temporal regulation of SAGs during senescence......Page 260
10.3.2 Regulation of SAGs by various endogenous and external factors......Page 261
10.3.3 Cis-acting regulatory elements of SAGs......Page 262
10.4 Molecular regulatory mechanisms of leaf senescence......Page 263
10.4.1 Developmental ageing......Page 264
10.4.2.1 Phytohormones......Page 267
10.4.2.2 Sugar signalling......Page 269
10.4.4 Regulatory role of protein degradation......Page 270
10.5 Conclusions and future challenges......Page 271
References......Page 272
11.2 Flower opening and senescence......Page 278
11.3 Model systems......Page 279
11.4.1 Ethylene......Page 280
11.4.2 Abscisic acid......Page 281
11.4.4 Gibberellic acid......Page 282
11.4.7 Polyamines......Page 283
11.4.8 Sugars......Page 284
11.5.1 Protein degradation......Page 285
11.5.3 Membrane degradation......Page 286
11.6 Petal senescence as programmed cell death......Page 287
11.7.1 Senescence-associated genes......Page 289
11.7.2 Functional analysis of SAGs......Page 290
11.7.2.2 Ethylene-independent senescence......Page 291
11.7.3 Regulation of petal senescence –a regulatory network?......Page 292
References......Page 294
12.1 Introduction......Page 300
12.2.2 Nonclimacteric ripening......Page 301
12.3.1 Tomato – the model for climacteric ripening......Page 302
12.3.2 Additional model systems for ripening research......Page 304
12.4.1 Cell-wall metabolism......Page 307
12.4.2 Ethylene biosynthesis and perception......Page 310
12.4.3 Global ripening control......Page 313
12.4.4 Modification of specific ripening pathways: pigmentation......Page 314
12.5 Summary......Page 316
References......Page 317
13.2 Strategies of manipulating leaf senescence......Page 326
13.3 IPT-based transgenic techniques for manipulation of cytokinin production......Page 327
13.4 Development of the SAG12-IPT autoregulatory cytokinin production system......Page 328
13.5 Use of the SAG12-IPT to manipulate senescence in crops......Page 329
13.5.1 IPT expression and cytokinin production in transgenic plants......Page 334
13.5.2 Delayed leaf senescence in the SAG-IPT plants......Page 335
13.5.4 Delayed postharvest senescence in the SAG12-IPT plants......Page 336
13.5.6 Increased stress tolerance in the SAG12-IPT plants......Page 337
13.6 Other strategies for manipulation of leaf senescence......Page 338
References......Page 339
Index......Page 345