SpTie1/2 is expressed in coelomocytes, axial organ and embryos of the sea urchin Strongylocentrotus purpuratus, and is an orthologue of vertebrate Tie1 and Tie2.
Stevens ME, Dhillon J, Miller CA, Messier-Solek C, Majeske AJ, Zuelke D, Rast JP, Smith LC. Dev Comp Immunol. 2010 Aug; 34(8):884-95. Epub 2010 Apr 10.