Gastrulation From Embryonic Pattern to Form

Cover
Series page
Copyright
Contributors
Preface
Preface
Acknowledgments
Chapter 1
Setting up for gastrulation: D. melanogaster
Introduction
Establishment of embryonic polarity occurs in oocytes
Navigating the maternal-to-zygotic transition
Gene expression patterns establish the prospective germ layers
Gene regulatory interactions prepare cells for diverse cell movements at gastrulation
Dynamic feedback between genetic patterning and physical tissue morphogenesis
References
Chapter 2
Setting up for gastrulation in zebrafish
Introduction
Maternal factors and dorsal-ventral patterning
Defining and delimiting dorsal: Maternal β-catenin with or without Wnt
Determinants at the vegetal pole
Turning BMP on by shutting down the organizer
Transforming blastula tissues to form the germ layers
It takes two to tango: TGFβ heterodimers specify mesendoderm
Exposure matters, inhibition needed, no feedback required when nodal organizes
Cohabiting or dwelling alone, location matters in mesendoderm patterning
Pattering along, toddler loses endoderm
Mom´s got skin in the game, patterning the ectoderm and the enveloping layer
Conclusion
Acknowledgments
References
Chapter 3
Signaling events regulating embryonic polarity and formation of the primitive streak in the chick embryo
Introduction
Embryonic regulation
Role of the posterior marginal zone in initiation of primitive streak formation
Molecular basis of primitive streak induction by the posterior marginal zone
cVg1 (GDF1)
Wnt8C
Pitx2
The hypoblast inhibits primitive streak formation
Hypoblast, endoblast and definitive endoderm
Formation and shaping of the primitive streak
Mechanisms ensuring that gastrulation is initiated only in one place
Inhibitors
Communication
Comparison to other model organisms
Summary and conclusions
References
Chapter 4
Comparative analysis of human and mouse development: From zygote to pre-gastrulation
Introduction
Pre-implantation development: From zygote to blastocyst formation
Implantation and the role of trophectoderm
Epiblast epithelization and pro-amniotic cavity formation
Pre-gastrulation patterning and establishment of the anterior-posterior axis
Conclusions
References
Further reading
Chapter 5
The cellular and molecular mechanisms that establish the mechanics of Drosophila gastrulation
Overview
Apical constriction: Force generation at the molecular and cellular level
Tissue invagination: Integrating cells across the tissue
RhoA signaling: Activating contractility and coordinating cell behavior
Gene regulation: Cell signaling centers and tissue geometry
Late gastrulation: Subsequent mesoderm EMT and spreading
Concluding remarks
References
Chapter 6
Cellular, molecular, and biophysical control of epithelial cell intercalation
Convergent extension: A conserved mechanism for shaping epithelia
Cell rearrangements during convergent extension in the Drosophila embryo
The molecular basis of epithelial cell intercalation
Biophysical control of epithelial cell intercalation
Breaking planar symmetry
Toll receptors direct planar polarity and cell intercalation
Regulation of planar polarity at compartment boundaries
Control of junctional and medial myosin by G protein-coupled receptors
Current questions and future challenges
Acknowledgments
References
Further reading
Chapter 7
Gastrulation in the sea urchin
A sequential overview of sea urchin gastrulation
Setting the stage for gastrulation: Specification of the vegetal plate
The pigment cells invade the blastocoel shortly after the skeletogenic cells
Mechanistic studies of primary invagination
Specification of endoderm
Cells at the tip of the advancing archenteron are necessary for establishing right-left asymmetry
Homing of the primordial germ cells to the coelomic pouches
Summary
Acknowledgments
References
Chapter 8
Tunicate gastrulation
Introduction: Tunicates-their place on the evolutionary tree and their contribution to our understanding of embryology
Events leading up to gastrulation
Cleavage patterns
Ooplasmic segregation/PEM
Origin of germ layers
Mechanisms of gastrulation
Endoderm-intrinsic forces in gastrulation
Gastrulation in other tunicates
Colonial tunicates
The thaliaceans: Salps, doliods and pyrosomes
Peri-gastrulation events
Notochord development
Neural induction and neurulation
Conclusion
Acknowledgments
References
Chapter 9
Mesoderm and endoderm internalization in the Xenopus gastrula
Introduction
Outline of Xenopus gastrulation
Bottle cell formation
Dorsal multilayer invagination
Apical layer processes
Deep cell movements
Convergent extension by parallel intercalation
Peak involution of the dorsal Xbra domain
Ventral internal involution
Orthogonal convergent extension of the dorsal Xbra domain
Internalization of the vegetal cell mass by ingression-type deep bottle cell migration
Blastopore closure
Conclusions
Acknowledgments
References
Chapter 10
Convergent extension in the amphibian, Xenopus laevis
Introduction
Active, force-producing CE occurs in presumptive notochordal and somitic mesoderm and in presumptive hindbrain-spinal ...
CE is driven by both radial intercalation (RI) and mediolateral intercalation (MI) of cells
Mechanisms underlying the RI component of CE
The mechanism and function of mediolateral intercalation behavior (MIB) in mesodermal CE
The node and cable network (NCN) and iterated actomyosin contraction is the ``power stroke´´ of MIB
Cell-on-cell traction rather than cell on matrix traction generates most of the tissue-level, tensile forces driving c ...
Balanced traction, regulation of contraction, and the logic of cell intercalation
An epithelial, junction remodeling model of notochordal cell intercalation
Comparison of the mesenchymal, cell-on-cell traction (CCT) model and the epithelial junction remodeling (EJR) model o ...
Computational models of CE by MIB mediated CCT
Large scale patterning of MIB is essential for Normal CE function
Patterning of mesodermal CE relative to other landmarks and presumptive tissues
Neural cell intercalation and CE
Forces and mechanics of the progressive expression of mesodermal MIB
Evaluating the contributions of the epithelial and deep layers to forces driving CE
The role of tissue boundary formation, Eph/Ephrin signaling, and tissue surface tension in CE
Late elongation and straightening of the body plan is driven by notochord straightening and elongation, and elongatio ...
Late endoderm elongation
CE as a large-scale mechanical patterning mechanism
Outlook
References
Chapter 11
Mechanisms of zebrafish epiboly: A current view
Introduction and overview
Setting the stage for epiboly
Epiboly initiation
Epiboly progression
EVL morphogenesis during epiboly progression
Deep cell movements
E-YSN and yolk cell microtubules
Conclusions and perspectives
Acknowledgments
References
Further reading
Chapter 12
Zebrafish gastrulation: Putting fate in motion
The fundamentals of germ layer specification and patterning
Nodal signaling and mesendoderm patterning
Setting up the Nodal signaling domain
Dose-dependent responses to Nodal signaling
Ectoderm specification: The default cell fate?
Shaping the zebrafish gastrula: Cell and tissue morphogenesis
Mesendoderm internalization movements
Dual role of Nodal signals in mesendoderm specification and internalization
Directed cell migration, a key mechanism to ensure germ layer segregation
Establishment of inside-out polarity in the zebrafish gastrula
Maintaining epiblast/hypoblast tissue boundary
Animal pole-directed mesendoderm migration-A path that comes in many flavors
Dorsal mesendoderm migration: Integrating autonomous cell motility amid a collective
Ventrolateral mesendoderm migration: The role of Apelin signaling
Endoderm migration-A `guided random walk?
Outlook
Acknowledgments
Glossary
References
Chapter 13
Cellular and molecular mechanisms of convergence and extension in zebrafish
Overview of zebrafish C&E
C&E of the mesoderm
Axial mesoderm: Chordamesoderm
Axial mesoderm: Prechordal plate
Paraxial mesoderm
Lateral mesoderm
Ventral mesoderm
C&E of the endoderm
C&E of the neuroectoderm
Neural plate
Neural keel
Interactions between germ layers influence C&E
Mesoderm-neuroectoderm interactions
Endoderm-mesoderm interactions
Concluding remarks
References
Chapter 14
Movements of chick gastrulation
Introduction: Morphology of the early embryo
Early movements in the epiblast position the gastrulation site before its formation
Initial positioning of gastrulation regulators
Rearrangement of the primitive streak precursors and global movements in the epiblast
Cooperative EMT triggers the formation of the initial primitive streak
Movements during gastrulation
Cell behaviors in the primitive streak
Tension created by ingression at the primitive streak drives movements in the entire epiblast
Movements into the lower layers
End of gastrulation stage
Summary and conclusions
References
Chapter 15
Guts and gastrulation: Emergence and convergence of endoderm in the mouse embryo
Preimplantation development, the blastocyst and emergence of the first endoderm population in the mouse
Anterior visceral endoderm (AVE), a derivative of the primitive endoderm (PrE) establishes the anterior-posterior axis ...
Gastrulation: Convergence of signals driving exit from pluripotency and acquisition of distinct cell identities in tim ...
Morphogenetic cell behaviors at the primitive streak: The gastrulation EMT
Morphogenetic cell behaviors driving gut endoderm formation
Gut endoderm morphogenesis coincides with germ layer segregation
Behavior of VE cells at the midline
Single-cell transcriptomic studies support the dual origin of the gut endoderm
The epigenetic landscape of embryonic (definitive) and extra-embryonic (visceral) endoderm
Mesendoderm and the mouse
Transforming the gut endoderm into the gut tube: Ventral folding
Patterning the gut tube and the emergence of organ identities
Concluding remarks
Acknowledgments
References