SpTie1/2 is expressed in coelomocytes, axial organ and embryos of the sea urchin Strongylocentrotus purpuratus, and is an orthologue of vertebrate Tiel and Tie2

作者：Stevens Margaret E; Dhillon Jatinder; Miller Chase A; Messier Solek Cynthia; Majeske Audrey J; Zuelke Dustin; Rast Jonathan P; Smith L Courtney^*

来源：Developmental and Comparative Immunology, 2010, 34(8): 884-895.

DOI：10.1016/j.dci.2010.03.010

• Echinoderm
• Receptor tyrosine kinase
• TEK
• Coelomocyte
• Axial organ
• Embryo

A full length cDNA sequence expressed in coelomocytes shows significant sequence match to vertebrate Tie1 and Tie2/TEK. Vertebrate Tie2/TEK is the receptor for the angiopoietins and plays an important role in angiogenesis and hematopoiesis. whereas Tie1 regulates the activity of Tie2. The deduced sequence of the SpTie1/2 protein has a similar order and organization of domains to the homologous vertebrate proteins including a highly conserved receptor tyrosine kinase domain in the cytoplasmic tail. The N terminus of the ectodomain has one immunoglobulin (Ig)-Tie2_1 domain, followed by an Ig domain, four epidermal growth factor domains, a second Ig domain, and three fibronectin type Ill domains. The SpTie1/2 gene is expressed in coelomocytes and the axial organ, whereas other organs do not show significant expression. The timing of embryonic expression corresponds with the differentiation of blastocoelar cells, the embryonic and larval immune cells. Searches of the sea urchin genome show several gene models encoding putative ligands and signaling proteins that might interact with SpTie1/2. We speculate that SpTie1/2 may be involved in the proliferation of sea urchin immune cells in both adults and embryos.

• 出版日期2010-8