There is also evidence to suggest that the fate of neural crest cells depends upon their migratory path in the trunk which is dictated by somites. Cells which migrate early move ventrally and pass through the anterior half sclerotome, form the sensory ganglia. Cells which are more dorsal within the anterior sclerotome form the sensory neurons and glia of the dorsal root ganglia, partly due to signals which come from the neural tube. Alternatively, the neural crest cells which migrate late travel laterally between the somite and the ectoderm, forming melanocytes in amniotes. It is thought that the increased complexity in vertebrate neuroanatomy may stem from interactions between neural crest cells and other cell types. An example of this is the essential role of neural crest cells in the expansion of the head and formation of a ‘true neck’. Neural crest cells are thought to be crucial in multiple stages of cranial mesoderm development and secrete signals which depress myogenesis, consequently allowing the formation of cranial myofibres. Research has suggested that these distinct myogenic regulatory sub-networks arose in early vertebrates. The formation of a ‘true neck’ is a result of the pectoral girdle losing its attachment to the skull, and allowed tetrapods to colonise land as they could now move their head independent of limbs. Despite
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for example neural tube defects (NTD). Folate Folate is a necessary vitamin part of the B complex group, not synthesized de novo, but consumed through foods such as leafy green vegetables (Djukic, 2007). In the developing fetus, folate transport across the placenta is regulated by reduced-folate-carriers and folate receptor proteins, which allow large folate requirements needed for high cell proliferation rates to be met. Both also show an increased pattern of expression during neural tube closure
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end of the neural tube and later leads to become a spinal cord (1,2). Development of the CNS involves many complex mechanisms beginning at the onset of transformation of a single layer of ectodermal cells, the neuroectoderm until the end of the differentiation process resulting into highly complex structure involving variety of neural cell types (1,2). A large number of cell types need to be arranged spatially and temporally to form a complex structure during an
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