Notochord definition

[wdahdul]

VAO:0000032 : notochord

VAO: Avascular multi-tissue structure composed of large vacuolated epithelial cells (chordablasts) and perichordal fibrous tissue.
UBR: The notochord is an elongate, rod-like, skeletal structure dorsal to the gut tube and ventral to the nerve cord. The notochord should not be confused with the backbone or vertebral column of most adult vertebrates. The notochord appears early in embryogeny and plays an important role in promoting or organizing the embryonic development of nearby structures. In most adult chordates the notochord disappears or becomes highly modified. In some non-vertebrate chordates and fishes the notochord persists as a laterally flexible but incompressible skeletal rod that prevents telescopic collapse of the body during swimming[TOLWEB]. a flexible, rod-shaped body found in embryos of all chordates. It is composed of cells derived from the mesoderm and defines the primitive axis of the embryo. In some chordates, it persists throughout life as the main axial support of the body, while in most vertebrates it becomes the vertebral body of the vertebral column. The notochord is found ventral to the neural tube. The notochord is composed primarily of a core of glycoproteins, encased in a sheath of collagen fibers wound into two opposing helices. The angle between these fibers determines whether increased pressure in the core will result in shortening and thickening versus lengthening and thinning[WP].

CJM-NOTES:Use VAO def. Retain portion of UBR def as gloss?

WD-notes: Seems fine to retain addition information from uberon definition.

[cmungall]

Changed to:

def: "Avascular multi-tissue structure composed of large vacuolated epithelial cells (chordablasts) and perichordal fibrous tissue[VAO]. The notochord is an elongate, rod-like, skeletal structure dorsal to the gut tube and ventral to the nerve cord. The notochord should not be confused with the backbone or vertebral column of most adult vertebrates. The notochord appears early in embryogeny and plays an important role in promoting or organizing the embryonic development of nearby structures. In most adult chordates the notochord disappears or becomes highly modified. In some non-vertebrate chordates and fishes the notochord persists as a laterally flexible but incompressible skeletal rod that prevents telescopic collapse of the body during swimming[TOLWEB]." [VAO:0000032, ISBN:0815318960, NLM:notochord, Wikipedia:Notochord, ZFIN:curator, http://tolweb.org/Chordata/2499, https://github.com//issues/25]