PubMed:8139691 JSONTXT

{"project":"AIMed","denotations":[{"id":"T1","span":{"begin":0,"end":3},"obj":"protein"},{"id":"T2","span":{"begin":24,"end":60},"obj":"protein"},{"id":"T3","span":{"begin":87,"end":123},"obj":"protein"},{"id":"T4","span":{"begin":177,"end":180},"obj":"protein"},{"id":"T5","span":{"begin":336,"end":339},"obj":"protein"},{"id":"T6","span":{"begin":552,"end":555},"obj":"protein"},{"id":"T7","span":{"begin":641,"end":669},"obj":"protein"},{"id":"T8","span":{"begin":703,"end":706},"obj":"protein"},{"id":"T9","span":{"begin":738,"end":741},"obj":"protein"},{"id":"T10","span":{"begin":775,"end":778},"obj":"protein"},{"id":"T11","span":{"begin":809,"end":812},"obj":"protein"},{"id":"T12","span":{"begin":814,"end":817},"obj":"protein"},{"id":"T13","span":{"begin":983,"end":986},"obj":"protein"}],"text":"B61 is a ligand for the ECK receptor protein-tyrosine kinase.\nA protein ligand for the ECK receptor protein-tyrosine kinase has been isolated by using the extracellular domain (ECK-X) of the receptor as an affinity reagent. Initially, concentrated cell culture supernatants were screened for receptor binding activity using immobilized ECK-X in a surface plasmon resonance detection system. Subsequently, supernatants from selected cell lines were fractionated directly by receptor affinity chromatography, resulting in the single-step purification of B61, a protein previously identified as the product of an early response gene induced by tumour necrosis factor-alpha. We report here that recombinant B61 induces autophosphorylation of ECK in intact cells, consistent with B61 being an authentic ligand for ECK. ECK is a member of a large orphan receptor protein-tyrosine kinase family headed by EPH, and we suggest that ligands for other members of this family will be related to B61, and can be isolated in the same way."}