Chordin (from Greek χορδή, string, catgut) is a protein with a prominent role in dorsal–ventral patterning during early embryonic development.
[1][2] Chordin was originally identified in the African clawed frog (Xenopus laevis) in the laboratory of Edward M. De Robertis as a key developmental protein that dorsalizes early vertebrate embryonic tissues.
Chordin is a 941 amino-acids long protein, whose three-dimensional transmission electron microscopy structure resembles a horseshoe.
These repeats are homologous with domains in a number of extracellular matrix proteins, including von Willebrand factor.
[6] Chordin function is improved by a few co-factors that include the Twisted Gastrulation gene (Tsg) and the zinc metalloprotease.
[13] Further experiments testing the role of both noggin and chordin showed that these two proteins are essential for mesodermal development and anterior pattern elaboration.
[13] When chordin was inactivated, animals may initially appear to have normal development, but later on issues manifest in the inner and outer ear along with pharyngeal and cardiovascular abnormalities.