PRINCIPLES OF DEVELOPMENTPDF电子书下载

Chapter 1： History and Basic Concepts 3

The origins of developmental biology 3

1-1 Aristotle first defined the problem of epigenesis and preformation 3

Box 1A Basic stages of Xenopus laevis development 4

1-2 Cell theory changed the conception of embryonic development and heredity 5

1-3 Mosaic and regulative development 6

1-4 The discovery of induction 8

1-5 The coming together of genetics and development 8

A conceptual tool kit 9

1-6 Development involves cell division， the emergence of pattern，change in form，cell differentiation，and growth 9

Box 1 B Germ layers 11

1-7 Cell behavior provides the link between gene action and developmental processes 12

1-8 Genes control cell behavior by controlling which proteins are made by a cell 13

1-9 Differential gene activity controls development 14

1-10 Development is progressive and the fate of cells becomes determined at different times 15

1-11 Inductive interactions can make cells different from each other 17

1-12 The response to inductive signals depends on the state of the cell 18

1-13 Patterning can involve the interpretation of positional information 19

1-14 Lateral inhibition can generate spacing patterns 20

1-15 Localization of cytoplasmic determinants and asymmetric cell division can make cells different from each other 20

1-16 The embryo contains a generative rather than a descriptive program 21

Chapter 2：Model Systems 25

Model organisms：vertebrates 25

2-1 Amphibians：Xenopus laevis 26

Box 2A Polar body formation 27

2-2 Birds：the chicken 31

2-3 Mammals：the mouse 37

2-4 Fishes：the zebrafish 41

Model organisms：invertebrates 43

2-5 The fruit fly Drosophila melanogaster 43

2-6 The nematode Caenorhabditis elegans 47

Model systems：plants 49

2-7 Arabidopsis thaliana 50

Identifying developmental genes 52

2-8 Developmental genes can be identified by rare spontaneous mutation 53

2-9 Identification of developmental genes by induced mutation and screening 54

Box 2B Mutagenesis and genetic screening for identifying developmental mutants in Drosophila 56

Chapter 3： Patterning the Vertebrate Body PlanI： Axes and Germ Layers 63

Setting up the body axes 63

3-1 The animal-vegetal axis of Xenopus is maternally determined 63

Box 3A Protein intercellular signaling molecules 64

Box 3B In situ detection of gene expression 65

3-2 The dorso-ventral axis of amphibian embryos is determined by the site of sperm entry 66

3-3 The Nieuwkoop center is specified by cortical rotation 68

3-4 Maternal proteins with dorsalizing and ventralizing effects have been identified 69

3-5 The dorso-ventral axis of the chick blastoderm is specified in relation to the yolk and the ante ro-posterior axis is set by gravity 70

3-6 The axes of the mouse embryo are specified by cell—cell interactions 71

3-7 Specification of left-right handedness of internal organs requires special mechanisms 73

3-8 Organ handedness in vertebrates is under genetic control 73

The origin and specification of the germ layers 75

3-9 A fate map of the amphibian blastula is constructed by following the fate of labeled cells 75

3-10 The fate maps of vertebrates are variations on a basic plan 77

3-11 Cells of early vertebrate embryos do not yet have their fates determined 79

Box 3C Transgenic mice 81

3-12 In Xenopus the mesoderm is induced by signals from the vegetal region 81

3-13 The mesoderm is induced by a diffusible signal during a limited period of competence 83

3-14 An intrinsic timing mechanism controls the time of expression of mesoderm-specific genes 84

3-15 Several signals induce and pattern the mesoderm in the Xenopus blastula 85

3-16 Sources of the mesoderm-inducing signals 86

3-17 Candidate mesoderm inducers have been identified in Xenopus 87

3-18 Mesoderm patterning factors are produced within the mesoderm 88

3-19 Zygotic gene expression begins at the mid-blastula transition in Xenopus 90

3-20 Mesoderm induction activates genes that pattern the mesoderm 91

3-21 Gradients in protein signaling factors and threshold responses could pattern the mesoderm 92

Chapter 4： Patterning the Vertebrate Body PlanⅡ： The Mesoderm and Early Nervous System 98

Somite formation and patterning 98

4-1 Somites are formed in a well-defined order along the ante ro-posterior axis 99

4-2 The fate of somite cells is determined by signals from the adjacent tissues 100

4-3 Positional identity of somites along the antero-posterior axis is specified by Hox gene expression 102

Box 4A Homeobox genes 104

4-4 Deletion or overexpression of Hox genes causes changes in axial patterning 106

4-5 Retinoic acid can alter positional values 107

Box 4B Gene targeting： insertional mutagenesis and gene knock-out 108

The role of the organizer region and neural induction 110

4-6 The organizer can specify a new antero-posterior axis 110

4-7 The neural plate is induced by mesoderm 113

4-8 The nervous system can be patterned by signals from the mesoderm 114

4-9 Signals that pattern the neural plate may travel within the neural plate itself 116

4-10 The hindbrain is segmented into rhombomeres by boundaries of cell lineage restriction 117

4-11 Neural crest cells have positional values 119

4-12 Hox genes provide positional identity in the hindbrain region 119

4-13 The embryo is patterned by the neurula stage into organ-forming regions that can still regulate 121

Chapter 5： Development of the Drosophila Body Plan 127

Maternal genes set up the body axes 127

5-1 Three classes of maternal genes specify the ante ro-posterior axis 128

5-2 The bicoid gene provides an ante ro-posterior morphogen gradient 129

5-3 The posterior pattern is controlled by the gradients of nanos and caudal proteins 131

5-4 The anterior and posterior extremities of the embryo are specified by cell-surface receptor activation 132

5-5 The dorso-ventral polarity of the egg is specified by localization of maternal proteins in the vitelline envelope 133

5-6 Positional information along the dorso-ventral axis is provided by the dorsal protein 134

Polarization of the body axes during oogenesis 136

5-7 Antero-posterior and dorso-ventral axes of the oocyte are specified by interactions with follicle cells 136

Zygotic genes pattern the early embryo 139

5-8 The expression of zygotic genes along the dorso-ventral axis is controlled by dorsal protein 139

5-9 The decapentaplegic protein acts as a morphogen to pattern the dorsal region 141

5-10 The ante ro-posterior axis is divided up into broad regions by gap gene expression 142

5-11 bicoid protein provides a positional signal for the anterior expression of hunchback 143

Box 5A Transgenic flies 144

5-12 The gradient in hunchback protein activates and represses other gap genes 144

Segmentation： activation of the pair-rule genes 146

5-13 Parasegments are delimited by expression of pair-rule genes in a periodic pattern 146

5-14 Gap gene activity positions stripes of pair-rule gene expression 148

Segment polarity genes and compartments 150

5-15 Expression of the engrailed gene delimits a cell lineage boundary and defines a compartment 151

Box 5B Genetic mosaics and mitotic recombination 153

5-16 Segment polarity genes pattern the segments and stabilize parasegment and segment boundaries 155

5-17 Compartment boundaries are involved in patterning and polarizing segments 157

5-18 Some insects use different mechanisms for patterning the body plan 158

Segmentation： selector and homeotic genes 161

5-19 Homeotic selector genes of the bithorax complex are responsible for diversification of the posterior segments 162

5-20 The Antennapedia complex controls specification of anterior regions 164

5-21 The order of HOM gene expression corresponds to the order of genes along the chromosome 164

5-22 HOM gene expression in visceral mesoderm controls the structure of the adjacent gut 165

Chapter 6：Development of Invertebrates，Ascidians，and Slime Molds 173

Nematodes 173

6-1 The developmental axes are determined by asymmetric cell division and cell—cell interactions 173

6-2 Cell—cell interactions specify cell fate in the early nematode embryo 176

6-3 A small cluster of homeobox genes specify cell fate along the antero-posterior axis 177

6-4 Genes control graded temporal information in nematode development 178

Molluscs 180

6-5 The handedness of spiral cleavage is specified maternally 181

6-6 Body axes in molluscs are related to early cleavages 181

Annelids 183

6-7 The teloblasts are specified by localization of cytoplasmic factors 183

6-8 Antero-posterior patterning and segmentation in the leech is linked to a lineage mechanism 184

Echinoderms 186

6-9 The sea urchin egg is polarized along the animal-vegetal axis 187

6-10 The dorso-ventral axis in sea urchins is related to the plane of the first cleavage 188

6-11 The sea urchin fate map is very finely specified，yet considerable regulation is possible 189

6-12 The vegetal region of the sea urchin embryo acts as an organizer 190

6-13 The regulatory regions of sea urchin develop-mental genes are complex and modular 191

Ascidians 193

6-14 Muscle may be specified by localized cytoplasmic factors 193

6-15 Notochord development in ascidians requires induction 195

Cellular slime molds 196

6-16 Patterning of the slug involves cell sorting and positional signaling 197

6-17 Chemical signals direct cell differentiation in the slime mold 199

Chapter 7： Plant Development 204

Embryonic development 204

7-1 Electrical currents are involved in polarizing the Fucus zygote 205

7-2 Cell fate in early Fucus development is determined by the cell wall 206

7-3 Differences in cell size resulting from unequal divisions could specify cell type in the Volvox embryo 207

7-4 Both asymmetric cell divisions and cell position pattern the early embryos of flowering plants 208

Box 7A Angiosperm embryogenesis 209

7-5 The patterning of particular regions of the Arabidopsis embryo can be altered by mutation 210

7-6 Plant somatic cells can give rise to embryos and seedlings 211

Meristems 213

7-7 The fate of a cell in the shoot meristem is dependent on its position 214

7-8 Meristem development is dependent on signals from the plant 217

Box 7B Transgenic plants 218

7-9 Leaf positioning and phyllotaxy involves lateral inhibition 218

7-10 Root tissues are produced from root apical meristems by a highly stereotyped pattern of cell divisions 219

Flower development 221

7-11 Homeotic genes control organ identity in the flower 221

7-12 The transition to a floral meristem is under environmental and genetic control 226

7-13 The Antirrhinum flower is patterned dorso-ventrally as well as radially 226

7-14 The internal meristem layer can specify floral meristem patterning 227

Chapter 8： Morphogenesis： Change in Form in the Early Embryo 232

Cell adhesion 232

8-1 Sorting out of dissociated cells demonstrates differences in cell adhesiveness in different tissues 232

Box 8A Cell adhesion molecules 233

8-2 Cadherins can provide adhesive specificity 234

Cleavage and formation of the blastula 235

8-3 The asters of the mitotic apparatus determine the plane of cleavage at cell division 237

8-4 Cells become polarized in early mouse and sea urchin blastulas 238

8-5 Ion transport is involved in fluid accumulation in the blastocoel 240

8-6 Internal cavities can be created by cell death 241

Gastrulation 242

8-7 Gastrulation in the sea urchin involves cell migration and invagination 243

Box 8B Change in cell shape and cell movement 244

8-8 Mesoderm invagination in Drosophila is due to changes in cell shape，controlled by genes that pattern the dorso-ventral axis 246

8-9 Xenopus gastrulation involves several different types of tissue movement 247

8-10 Convergent extension and epiboly are due to cell intercalation 250

8-11 Notochord elongation is caused by cell intercalation 252

Neural tube formation 254

8-12 Neural tube formation is driven by both internal and external forces 254

8-13 Changes in the pattern of expression of cell adhesion molecules accompany neural tube formation 255

Cell migration 256

8-14 The directed migration of sea urchin primary mesenchyme cells is determined by the contacts of their filopodia to the blastocoel wall 257

8-15 Neural crest migration is controlled by environ-mental cues and adhesive differences 258

8-16 Slime mold aggregation involves chemotaxis and signal propagation 260

Directed dilation 262

8-17 Circumferential contraction of hypodermal cells elongates the nematode embryo 263

8-18 The direction of cell enlargement can determine the form of a plant leaf 263

Chapter 9： Cell Differentiation 271

The reversibility and inheritance of patterns of gene activity 271

9-1 Nuclei of differentiated cells can support develop-ment of the egg 272

9-2 Patterns of gene activity in differentiated cells can be changed by cell fusion 273

9-3 The differentiated state of a cell can change by transdifferentiation 274

9-4 Differentiation of cells that make antibodies is due to irreversible changes in their DNA 276

9-5 Maintenance and inheritance of patterns of gene activity may depend on regulatory proteins，as well as chemical and structural modifications of DNA 277

Control of specific gene expression 281

9-6 Control of transcription involves both general and tissue-specific transcriptional regulators 282

9-7 External signals can activate genes 284

Models of cell differentiation 287

9-8 A family of genes can activate muscle-specific transcription 287

9-9 The differentiation of muscle cells involves withdrawal from the cell cycle 288

9-10 Complex combinations of transcription factors control cell differentiation 289

9-11 All blood cells are derived from pluripotent stem cells 290

9-12 Colony-stimulating factors and intrinsic changes control differentiation of the hematopoietic lineages 291

9-13 Globin gene expression is controlled by distant upstream regulatory sequences 293

9-14 Neural crest cells differentiate into several cell types 295

9-15 Steroid hormones and polypeptide growth factors specify chromaffin cells and sympathetic neurons 297

9-16 Neural crest diversification involves signals for both specification of cell fate and selection for cell survival 297

9-17 Programmed cell death is under genetic control 298

Chapter 10：Organogenesis 304

The development of the chick limb 304

10-1 The vertebrate limb develops from a limb bud 305

10-2 Patterning of the limb involves positional information 305

10-3 The apical ectodermal ridge induces the progress zone 307

10-4 The polarizing region specifies position along the ante ro-posterior axis 308

10-5 Position along the proximo-distal axis may be specified by a timing mechanism 311

10-6 The dorso-ventral axis is controlled by the ectoderm 312

10-7 Different interpretations of the same positional signals give different limbs 312

10-8 Homeobox genes are involved in patterning the limbs and specifying their position 313

10-9 Self-organization may be involved in pattern formation in the limb bud 315

10-10 Limb muscle is patterned by the connective tissue 316

Box 10A Reaction-diffusion mechanisms 317

10-11 The initial development of cartilage， muscles，and tendons is autonomous 318

10-12 Separation of the digits is the result of programmed cell death 318

Insect imaginal discs 320

10-13 Signals from the ante ro-posterior compartment boundary pattern the wing imaginal disc 321

10-14 The dorso-ventral boundary of the wing acts as a pattern-organizing center 322

10-15 The leg disc is patterned in a similar manner to the wing disc，except for the proximo-distal axis 323

10-16 Butterfly wing markings are organized by additional positional fields 324

10-17 The segmental identity of imaginal discs is determined by the homeotic selector genes 325

The insect compound eye 328

10-18 Signals maintain progress of the morpho-genetic furrow and the ommatidia are spaced by lateral inhibition 329

10-19 The patterning of the cells in the ommatidium depends on intercellular interactions 329

10-20 The development of R7 depends on a signal from R8 330

10-21 Activation of the gene eyeless can initiate eye development 331

The nematode vulva 332

10-22 The anchor cell induces primary and secondary fates 333

Development of the kidney 334

10-23 The development of the ureteric bud and mesen-chymal tubules involves induction 334

Chapter 11： Development of the Nervous System 340

Specification of cell identity in the nervous system 340

11-1 Neurons in Drosophila arise from proneural clusters 340

11-2 Lateral inhibition allocates neuronal precursors 342

11-3 Asymmetric cell divisions are involved in Drosophila sensory organ development 343

11-4 The vertebrate nervous system is derived from the neural plate 344

11-5 Specification of vertebrate neuronal precursors involves lateral inhibition 345

11-6 The pattern of differentiation of cells along the dorso-ventral axis of the spinal cord depends on ventral and dorsal signals 346

11-7 Neurons in the mammalian central nervous system arise from asymmetric cell divisions，then migrate away from the proliferative zone 348

Axonalguidance 352

11-8 Motor neurons from the spinal cord make muscle-specific connections 353

11-9 The growth cone controls the path taken by the growing axon 354

11-10 Choice of axon pathway depends on environmental cues and neuronal identity 355

11-11 Neurons from the retina make ordered connections on the tectum to form a retino-tectal map 356

11-12 Axons may be guided by gradients of diffusible agents 358

Neuronal survival， synapse formation， and refinement 360

11-13 Many motor neurons die during limb innervation 361

11-14 Neuronal survival depends on competition for neurotrophic factors 361

11-15 Reciprocal interactions between nerve and muscle are involved in formation of the neuromuscular junction 362

11-16 The map from eye to brain is refined by neural activity 365

11-17 The ability of mature vertebrate axons to regenerate is restricted to peripheral nerves 367

Chapter 12：Germ Cells and Sex 372

Determination of the sexual phenotype 372

12-1 The primary sex-determining gene in mammals is on the Y chromosome 372

12-2 Mammalian sexual phenotype is regulated by gonadal hormones 373

12-3 In Drosophila， the primary sex-determining signal is the number of X chromosomes and is cell autonomous 374

12-4 Somatic sexual development in Caenorhabditis is determined by the number of X chromosomes 376

12-5 Most flowering plants are hermaphrodites，but some produce unisexual flowers 377

12-6 Germ cell sex determination may depend both on cell signals and genetic constitution 378

12-7 Various strategies are used for dosage compen-sation of X-linked genes 379

The development of germ cells 382

12-8 Germ cell fate can be specified by a distinct germ plasm in the egg 382

12-9 Pole plasm becomes localized at the posterior end of the Drosophila egg 384

12-10 Germ cells migrate from their site of origin to the gonad 384

12-11 Germ cell differentiation involves a reduction in chromosome number 385

12-12 Oocyte development can involve gene amplifi-cation and contributions from other cells 387

12-13 Genes controlling embryonic growth are imprinted 387

Fertilization 390

12-14 Fertilization involves cell-surface interactions between egg and sperm 391

12-15 Changes in the egg membrane at fertilization block polyspermy 392

12-16 A calcium wave initiated at fertilization results in egg activation 393

Chapter 13：Regeneration 401

Morphallaxis 401

13-1 Hydra grows continuously， with loss of cells from its ends and by budding 401

13-2 Regeneration in Hydra is polarized and does not depend on growth 402

13-3 The head region of Hydra acts both as an organizing region and as an inhibitor of inappropriate head formation 402

13-4 Head regeneration in Hydra can be accounted for in terms of two gradients 403

Epimorphosis 405

13-5 Vertebrate limb regeneration involves cell dedifferentiation and growth 406

13-6 The limb blastema gives rise to structures with positional values distal to the site of amputation 408

13-7 Retinoic acid can change proximo-distal positional values in regenerating limbs 410

13-8 Insect limbs intercalate positional values by both proximo-distal and circumferential growth 412

13-9 Polarized regeneration in plants is due to the polarized transport of auxin 413

Chapter 14： Growth and Post-Embryonic Development 418

Growth 418

14-1 Tissues can grow by cell proliferation，cell enlargement，or accretion 418

14-2 Cell proliferation can be controlled by an intrinsic program and by external signals 419

14-3 Growth of mammals is dependent on growth hormones 421

14-4 Developing organs can have their own intrinsic growth programs 423

14-5 Growth of the long bones occurs in the growth plates 424

14-6 Growth of vertebrate striated muscle is dependent on tension 426

14-7 The epithelia of adult mammalian skin and gut are continually replaced by derivatives of stem cells 426

14-8 Cancer can result from mutations in genes controlling cell multiplication and differentiation 430

14-9 Hormones control many features of plant growth 430

14-10 Cell enlargement is central to plant growth 431

Molting and metamorphosis 432

14-11 Arthropods have to molt in order to grow 433

14-12 Metamorphosis is under environmental and hormonal control 434

Aging and senescence 437

14-13 Genes can alter the timing of senescence 438

14-14 Cells senesce in culture 439

Chapter 15： Evolution and Development 444

Modification of development in evolution 444

15-1 Embryonic structures have acquired new functions during evolution 445

15-2 Limbs evolved from fins 446

15-3 Development of vertebrate and insect wings makes use of evolutionarily conserved mechanisms 449

15-4 Hox gene complexes have evolved through gene duplication 450

15-5 Changes in specification and interpretation of positional identity have generated the elaboration of vertebrate and arthropod body plans 451

15-6 The position and number of paired appendages in insects is dependent on Hox gene expression 453

15-7 The body plan of arthropods and vertebrates is similar，but the dorso-ventral axis is inverted 454

Changes in the timing of developmental processes during evolution 456

15-8 Changes in relative growth rates can alter the shapes of organisms 456

15-9 Evolution of life histories has implications for development 457

15-10 The timing of developmental events has changed during evolution 458