Since its identification in 1927, the mouse T (Brachyury) locus has be
en implicated in mesoderm formation and and notochord differentiation
Recent work; has demonstrated that this gene encodes a putative transc
ription factor expressed specifically in nascent mesoderm and in the d
ifferentiating notochord. Homologous genes have been cloned from the f
rog Xenopus laevis, the zebrafish Brachydanio rerio and the ascidian H
alocynthia roretzi. The T gene is an important tool for elucidating me
sodermal and embryonic pattern formation.