Developmental Timing

Series Page

Contributors

Preface

Chapter One. How Clocks and Hormones Act in Concert to Control the Timing of Insect Development

1 General Considerations: The Problem of Time in Development

2 Evidence for Mechanisms Controlling the Timing of Developmental Events

3 Developmental Timing in Insects is Under Hormonal Control

4 Circadian Control and Developmental Transitions

5 Circadian Core Clock in Flies

6 Evidence of a Clock in the Insect Prothoracic Glands

7 Circadian Oscillations of EcR

8 Oscillations in the Prothoracic Gland: Input from the Brain

9 The Timing of CCAP Neuronal Differentiation is Ecdysone-Controlled

10 JHs and Developmental Timing

11 Outlook

References

Chapter Two. Nutrient Signaling and Developmental Timing of Maturation

1 Introduction

2 Interplay Between Nutrients, Systemic Growth, and Developmental Transitions

3 A Nutritional Checkpoint Based on Crosstalk Between Different Tissues

4 Fine-Tuning Systemic Insulin Signaling

5 A Developmental Checkpoint Couples Organ Growth and Tissue Regeneration to Timing

6 Conclusions and Perspectives

Acknowledgments

References

Chapter Three. Temporal Patterning of Neural Progenitors in Drosophila

1 Introduction

2 Sequentially Expressed Transcription Factors in NBs Control Birth-Order-Dependent Neuron Fates

3 How are Temporal Transitions in NBs Controlled?

4 Relationship Between Temporal Sequence and NB Competence

5 Feedforward Loops Downstream of the Temporal Sequence Control Neuron Fates

6 Progression of the TF Sequence Required for the End of Neurogenesis

7 Integration of Temporal and Spatial Information Determines Lineages

8 Integration of Temporal Identity with Binary Fate Choice

9 Conclusions and Future Questions

References

Chapter Four. MicroRNAs as Components of Systemic Signaling Pathways in Drosophila melanogaster

1 Introduction

2 Overview of miRNA Biogenesis and Function

3 Insulin and Nutritional Pathways

4 Lipophilic Hormone Signaling Pathways

5 Light Modulated Circadian Rhythm Pathways

6 Stress Induced and Immune Response Pathways

7 Summary

References

Chapter Five. Vegetative Phase Change and Shoot Maturation in Plants

1 Introduction

2 Terminology

3 Heteroblasty and Vegetative Phase Change

4 miR156 and miR157: Master Regulators of Vegetative Phase Change

5 miR156 Targets

6 Molecular Insights into the Phenomenology of Vegetative Phase Change

7 Conclusion

Acknowledgments

References

Chapter Six. Developmental Transitions in C. elegans Larval Stages

1 Introduction

2 A Worm Well-Suited to Timing Studies

3 Heterochronic Mutants

4 microRNA Switches

5 LIN-28: A microRNA Regulator at the Pathway’s Center

6 The Heterochronic Pathway

7 Developmental Transitions: The Molts

8 LIN-42: A Link Between Molting and Developmental Decisions

9 Reversible Interruption of Developmental Progression: DAF-12

10 Interrupted Development: Reprogramming and Resynchronization

11 Launching Larval Development

12 A Heterochronic Pathway for Larger Animals?

13 Conclusions and Future Directions

Acknowledgments

References

Chapter Seven. Steroid Regulation of C. elegans Diapause, Developmental Timing, and Longevity

1 Introduction

2 Endocrine Regulation of the Dauer Diapause

3 DAF-12 Regulates Developmental Timing

4 Hormonal Control of Longevity

5 Perspectives

Acknowledgments

References

Chapter Eight. Diapause: Delaying the Developmental Clock in Response to a Changing Environment

1 Introduction

2 Hormonal Control of Embryonic Diapause in Insects: The “Hatch-Ready” Example

3 Hormonal Control of Insect Diapause: The Mid-Embryonic Arrest Example

4 Developmental Control of Larval Diapause

5 Pupal Diapause

6 Diapause Can Modify Larval/Pupal Growth

7 Seasonal Polyphenisms Correlate with Diapause

8 The Killifish Diapausing Embryo: A Developmental Analogy in a Vertebrate

9 Summary and Perspective

Acknowledgments

References

Chapter Nine. Circannual Transitions in Gene Expression: Lessons from Seasonal Adaptations

1 Introduction

2 Seasonal Courtship and Territorial Behavior

3 Migration

4 Hibernation

5 Potential Pathways Involved in Circannual Timing

6 Recent Advances in Circannual Timing Research

7 Conclusions: Future Directions and Potential Applications

Acknowledgments

References

Chapter Ten. Unliganded Thyroid Hormone Receptor Regulates Metamorphic Timing via the Recruitment of Histone Deacetylase Complexes

1 Introduction

2 TR Function During Frog Development

3 Unliganded TR Recruits Corepressor Complexes to Control Metamorphic Timing

4 Coactivator Recruitment for Metamorphic Progression

5 Temporal Regulation of Organ-Specific Metamorphosis

6 Conclusions

Acknowledgment

References

Chapter Eleven. Keeping Puberty on Time: Novel Signals and Mechanisms Involved

1 Puberty is a Key Developmental Transition

2 Neurobiology of Puberty: Essential Roles of GnRH and Kiss1 Neurons

3 Putative Roles of Kisspeptin Partners in the Control of Puberty: The Case of NKB

4 Early Development and the Timing of Puberty: Kiss1 Neurons in Brain Sex Differentiation

5 Metabolic Control of Puberty: Leptin, Kisspeptins, and Cellular Energy Sensors

6 Novel Mechanisms in the Control of Puberty: Roles of Epigenetics and microRNAs

7 Concluding Remarks

Acknowledgments

References

Index