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Molecular cloning of a ligand for the EPH-related receptor protein-tyrosine kinase Htk.

ABSTRACT: Htk is a receptor protein-tyrosine kinase that is related to the EPH subfamily of tyrosine kinases. The receptor has a wide tissue distribution including expression in several myeloid hematopoietic cell lines. Using an Htk-Fc fusion protein, a protein ligand for this receptor was expression cloned from the murine kidney mesangial cell line SV40MES 13. The Htk ligand cDNA encodes a transmembrane protein of 336 amino acids. Binding competition experiments demonstrated a Kd of 535 pM for binding of Htk-Fc to the Htk ligand. Incubation of 3T3 cells expressing Htk with COS-7 cells expressing the ligand resulted in tyrosine phosphorylation of Htk. The ligand, like its receptor, is widely expressed and may function in a variety of tissues. However, we localized hematopoietic expression of Htk to the monocytic lineage, suggesting that the ligand may play a role in differentiation and/or proliferation of these cells.

SUBMITTER: Bennett BD

PROVIDER: S-EPMC42383 | biostudies-other | 1995 Mar

REPOSITORIES: biostudies-other

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Molecular cloning of a ligand for the EPH-related receptor protein-tyrosine kinase Htk.

Bennett B D BD Zeigler F C FC Gu Q Q Fendly B B Goddard A D AD Gillett N N Matthews W W

Proceedings of the National Academy of Sciences of the United States of America 19950301 6

Htk is a receptor protein-tyrosine kinase that is related to the EPH subfamily of tyrosine kinases. The receptor has a wide tissue distribution including expression in several myeloid hematopoietic cell lines. Using an Htk-Fc fusion protein, a protein ligand for this receptor was expression cloned from the murine kidney mesangial cell line SV40MES 13. The Htk ligand cDNA encodes a transmembrane protein of 336 amino acids. Binding competition experiments demonstrated a Kd of 535 pM for binding of ...[more]

PMID: 7534404

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