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The neural crest is a ridge-like structure that is formed transiently between the epidermal ectoderm and neural plate during vertebrate development. Neural crest cells originate from this structure through the epithelial-mesenchymal transition, and in turn give rise to a diverse cell lineage—including melanocytes, craniofacial cartilage and bone, smooth muscle, dentin, peripheral and enteric ...
Neural crest cells form ganglia above each rhombomere. The early neural tube is primarily composed of the germinal neuroepithelium, later called the ventricular zone, which contains primary neural stem cells called radial glial cells and serves as the main source of neurons produced during brain development through the process of neurogenesis ...
Cells from both the mesodermal and the ectodermal tissues contribute to the formation of the eye. Specifically, the eye is derived from the neuroepithelium, surface ectoderm, and the extracellular mesenchyme which consists of both the neural crest and mesoderm. [2] [3] [4] Neuroepithelium forms the retina, ciliary body, iris, and optic nerves.
These genes determine the basic structure and orientation of an organism after the embryonic segments have formed. [1] The neural crest cells that are found outside of a given neuromere will express the same proteins as the cells that are found inside the neural tube. [1]
Histologically, these cells are classified as pseudostratified columnar cells. [ 1 ] After recruitment from the ectoderm, the neuroectoderm undergoes three stages of development: transformation into the neural plate , transformation into the neural groove (with associated neural folds ), and transformation into the neural tube .
The face and neck development of the human embryo refers to the development of the structures from the third to eighth week that give rise to the future head and neck.They consist of three layers, the ectoderm, mesoderm and endoderm, which form the mesenchyme (derived form the lateral plate mesoderm and paraxial mesoderm), neural crest and neural placodes (from the ectoderm). [1]
In the fourth week—during the neurulation stage—the neural folds close to form the neural tube, bringing together the neural crest cells at the neural crest. [67] The neural crest runs the length of the tube with cranial neural crest cells at the cephalic end and caudal neural crest cells at the tail. Cells detach from the crest and migrate ...
Each of these three components will give rise to a particular complement of cells. The neural tube cells give rise to the central nervous system, neural crest cells give rise to the peripheral and enteric nervous system, melanocytes, and facial cartilage, and the epidermal region will give rise to the epidermis, hair, nails, sebaceous glands ...