Cranial Placodes And Neural Crest Interactions In Craniofacial Development

Craniofacial development is a multistep and intricate process initially involving a number of inductive interactions that control neural and neural crest development, which are followed by a series of epithelial-mesenchymal interactions that control outgrowth, patterning, and skeletal differentiation. Certain aspects of craniofacial development are unique developmental processes in higher vertebrates. First, in higher vertebrates the cranial neural crest, in contrast to the trunk neural crest, gives rise to the skeletal structures. These skeletal elements include those comprising mem brane bone and secondary cartilage, which with the exception of the clavicle are tissue types found exclusively in the head in higher vertebrates. Second, with the exception of the tongue, the origin of the musculature is distinct from other regions of the body. The body and tongue muscles are formed from the segmented epithelial somites whilst the head musculature is formed from unsegmented paraxial and prechordal mesoderm. Furthermore, the signalling cascades that control myogenic differentia tion appear to be distinct as determined by gene expression and the response of myogenic cells to growth factors. Finally, the neurogenic placodes, which give rise to the sensory organs and some cranial ganglia, are only found in the head. Over recent years, there have been significant advances in our knowledge of the molecular proc esses that control craniofacial development in a number of animal models. This has given insight into the genes that control many aspects of head development from the initial induction of the head to the final stages of differentiation.

Craniofacial development is a multistep and intricate process initially involving a number of inductive interactions that control neural and neural crest development, which are followed by a series of epithelial-mesenchymal interactions that control outgrowth, patterning, and skeletal differentiation. Certain aspects of craniofacial development are unique developmental processes in higher vertebrates. First, in higher vertebrates the cranial neural crest, in contrast to the trunk neural crest, gives rise to the skeletal structures. These skeletal elements include those comprising mem brane bone and secondary cartilage, which with the exception of the clavicle are tissue types found exclusively in the head in higher vertebrates. Second, with the exception of the tongue, the origin of the musculature is distinct from other regions of the body. The body and tongue muscles are formed from the segmented epithelial somites whilst the head musculature is formed from unsegmented paraxial and prechordal mesoderm. Furthermore, the signalling cascades that control myogenic differentia tion appear to be distinct as determined by gene expression and the response of myogenic cells to growth factors. Finally, the neurogenic placodes, which give rise to the sensory organs and some cranial ganglia, are only found in the head. Over recent years, there have been significant advances in our knowledge of the molecular proc esses that control craniofacial development in a number of animal models. This has given insight into the genes that control many aspects of head development from the initial induction of the head to the final stages of differentiation.

Written by an international panel of recognized leaders in the field, Neural Crest Induction and Differentiation discusses all aspects of modern neural crest biology from its evolutionary significance to its specification, migration, plasticity and contribution to multiple lineages of the vertebrate body, to the pathologies associated with abnormal neural crest development and function. Abundant color figures enhance the text providing clear and attractive illustrations of central issues and concepts.

Most of the cranial sense organs of vertebrates arise from embryonic structures known as cranial placodes. Such placodes also give rise to sensory neurons that transmit information to the brain as well as to many neurosecretory cells. This book focuses on the development of sensory and neurosecretory cell types from cranial placodes by introducing the vertebrate head with its sense organs and neurosecretory organs and providing an overview of the various cranial placodes and their derivatives, including evidence of common embryonic primordia. Schlosser discusses how these primordia are established in the early embryo and how individual placodes develop. The latter chapters explain how various placodally derived sensory and neurosecretory cell types differentiate into discrete structures.

The neural crest is a remarkable embryonic population of cells found only in vertebrates and has the potential to give rise to many different cell types contributing throughout the body. These derivatives range from the mesenchymal bone and cartilage comprising the facial skeleton, to neuronal derivatives of the peripheral sensory and autonomic nervous systems, to melanocytes throughout the body, and to smooth muscle of the great arteries of the heart. For these cells to correctly progress from an unspecifi ed, nonmigratory population to a wide array of dynamic, differentiated cell types—some of which retain stem cell characteristics presumably to replenish these derivatives—requires a complex network of molecular switches to control the gene programs giving these cells their defi ning structural, enzymatic, migratory, and signaling capacities. This review will bring together current knowledge of neural crest-specifi c transcription factors governing these progressions throughout the course of development. A more thorough understanding of the mechanisms of transcriptional control in differentiation will aid in strategies designed to push undifferentiated cells toward a particular lineage, and unraveling these processes will help toward reprogramming cells from a differentiated to a more naive state. Table of Contents: Introduction / AP Genes / bHLH Genes / ETS Genes / Fox Genes / Homeobox Genes / Hox Genes / Lim Genes / Pax Genes / POU Domain Genes / RAR/RXR Genes / Smad Genes / Sox Genes / Zinc Finger Genes / Other Miscellaneous Genes / References / Author Biographies

Neural Crest Cells: Evolution, Development and Disease summarizes discoveries of historical significance and provides in-depth, current analyses of the evolution of neural crest cells, their contribution to embryo development, and their roles in disease. In addition, prospects for tissue engineering, repair and regeneration are covered, offering a timely synthesis of the current knowledge in neural crest cell research. A comprehensive resource on neural crest cells for researchers studying cell biology, developmental biology, stem cells and neurobiology, Neural Crest Cells: Evolution, Development and Disease provides foundational information needed for students , practicing physicians and dentists treating patients with craniofacial defects. BMA Medical Book Awards 2014 - Highly Commended,Basic and Clinical Sciences,2014, British Medical Association Provides timely, comprehensive synthesis of the current knowledge of neural crest cells Covers the evolution and development of neural crest cells Includes content on applications for tissue engineering, repair and regeneration