angiopoietin receptor angiopoietin receptor the angiopoietin receptors are receptors that bind angiopoietin. tie-1 and tie-2 comprise the cell-surface receptors that bind and are activated by the angiopoietins, (ang1, ang2, ang3, ang4). the angiopoietins are protein growth factors required for the formation of blood vessels (angiogenesis). angiopoietin receptoridentifierssymboltiepfampf10430interproipr018941membranome1214available protein structures:pfam structures / ecod pdbrcsb pdb; pdbe; pdbjpdbsumstructure summary tyrosine kinase with immunoglobulin-like and egf-like domains 1identifierssymboltie1alt. symbolstie, jtk14ncbi gene7075hgnc11809omim600222refseqnm_005424uniprotp35590other dataec number2.7.1.112locuschr. 1 p34-p33search forstructuresswiss-modeldomainsinterpro tek tyrosine kinase, endothelialidentifierssymboltekalt. symbolstie2, tie-2, vmcm1, cd202bncbi gene7010hgnc11724omim600221refseqnm_000459uniprotq02763other datalocuschr. 9 p21search forstructuresswiss-modeldomainsinterpro angiopoietins the angiopoietins are protein growth factors that regulate angiogenesis, the formation of blood vessels. in humans, three angiopoietins have been identified: ang1, ang2, and ang4 (ang 3 is the mouse ortholog of human ang4). ang1 and ang4 function as agonistic or activating ligands for tie2, whereas ang2 and ang3 behave as competitive antagonists. they function by binding their physiologic receptors, tie-1 and tie-2. these are receptor tyrosine kinases, so named because they mediate cell signals by inducing the phosphorylation of key tyrosines, thus initiating cell signalling. it is somewhat controversial which of the tie receptors mediate functional signals downstream of ang stimulation. but it is clear that at least tie-2 is capable of physiologic activation as a result of binding the angiopoietins.