Somites are spheres of epithelial cells that form sequentially along the anterior-posterior axis of the embryo through mesenchymal to epithelial transition of the presomitic mesoderm. [ http://dx.doi.org/10.1111/j.1439-0426.2012.01987.x http://en.wikipedia.org/wiki/Somite ]
Term information
- AAO:0010569
- FMA:85522
- XAO:0000058
- EHDAA:699
- ZFA:0000155
- BTO:0001558
- UMLS:C0376449 (ncithesaurus:Somite)
- MESH:D019170
- NCIT:C34302
- AEO:0001015
- EMAPA:31169
- GAID:1306
- TAO:0000155
- EHDAA:366
- MIAA:0000068
- EHDAA2:0003436
- Wikipedia:Somite
- MAT:0000068
- VHOG:0000191
uberon_slim, pheno_slim, vertebrate_core
relationship loss: develops_from paraxial mesenchyme (TAO:0000942)[TAO]
relationship type change: part_of paraxial mesoderm (AAO:0010568) CHANGED TO: develops_from paraxial mesoderm (UBERON:0003077)[AAO]
relationship type change: OBO_REL:part_of trunk (TAO:0001115) CHANGED TO: develops_from trunk (UBERON:0002100)[TAO]
When the somite becomes segmented from the segmental plate, it is composed of an epithelial sac enclosing mesenchymal somitocoel cells. Thereafter the somite differentiates into two parts, the ventro-medial mesenchymal sclerotome and the dorso-lateral epithelial dermomyotome. This change in the epithelial somite depends on surrounding tissue [PMID:15906248]
EDITOR_NOTE currently classified as an epithelial vesicle, consistent with EHDAA2 and https://github.com/obophenotype/uberon/wiki/The-neural-crest. Consider making 'somitic mesoderm' a separate term and correlate with regionalization processes. Consider moving ZFA term to 'trunk somite' as it is part of the trunk
Undifferentiated mesodermal components of early trunk or tail segments or metameres, derived from paraxial mesoderm; forms myotomes, sclerotomes and perhaps dermatomes. Kimmel et al, 1995.[TAO]
Post-cranial axial segments which form sclerotome and dermomyotome.[AAO]
(...) cephalocordates and craniates belong to a group known as Somitichordata. Somitichordate synapomorphies include (1) somites (...) (reference 1); The idea that the last common ancestor of bilaterian animals (Urbilateria) was segmented has been raised recently on evidence coming from comparative molecular embryology (reference 2).[well established][VHOG]
Term relations
- epithelial vesicle
- developing anatomical structure
- in taxon some Chordata
- in taxon some (not Tunicata)
- develops from some presomitic mesoderm