Angiopoietin-2, a Natural Antagonist for Tie2 That Disrupts in vivo Angiogenesis

• DOI: 10.1126/science.277.5322.55
• Publication Date: 2002-07-27T05:50:55Z
• Authors: Peter C. Maisonpi...; Chitra Suri; Pamela F. Jones; Sona Bartunkova; Stanley J. Wiegand; Czeslaw Radziejewski; Debra Compton; Joyce McClain; Thomas H. Aldrich; Nick Papadopoulos; Thomas J. Daly; Samuel Davis; Thomas N. Sato; George D. Yancopo...
• Keywords: Angiopoietin receptor; Angiopoietin

Angiogenesis is thought to depend on a precise balance of positive and negative regulation. Angiopoietin-1 (Ang1) an angiogenic factor that signals through the endothelial cell–specific Tie2 receptor tyrosine kinase. Like vascular growth factor, Ang1 essential for normal development in mouse. An relative, termed angiopoietin-2 (Ang2), was identified by homology screening shown be naturally occurring antagonist Tie2. Transgenic overexpression Ang2 disrupts blood vessel formation mouse embryo. In adult mice humans, expressed only at sites remodeling. Natural antagonists vertebrate kinases are atypical; thus, discovery regulator acting emphasizes need exquisite regulation this system.