Isolation and characterization of a novel receptor-type protein tyrosine kinase (hek) from a human pre-B cell line.

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Citation

Boyd AW, Ward LD, Wicks IP, Simpson RJ, Salvaris E, Wilks A, Welch K, Loudovaris M, Rockman S, Busmanis I

Isolation and characterization of a novel receptor-type protein tyrosine kinase (hek) from a human pre-B cell line.

J Biol Chem. 1992 Feb 15;267(5):3262-7.

PubMed ID
1737782 [ View in PubMed
]
Abstract

In this report we describe the identification and characterization of a novel tumor-associated receptor-type tyrosine kinase (hek). We produced a monoclonal antibody (III.A4) that detected a novel glycoprotein on the immunizing pre-B cell acute lymphoblastic leukemia cell line (LK63). This antigen was shown to be expressed sporadically on hemopoietic tumor cell lines and on ex vivo tumors. However, using antibody staining, the molecule was undetectable on normal tissues. Further biochemical characterization showed this molecule (hek) to be a phosphoroprotein. This observation taken together with the tumor-associated nature of hek expression suggested that hek might be a receptor-type protein tyrosine kinase. This was demonstrated by affinity purification of hek. In in vitro kinase experiments the purified hek protein was autophosphorylated on tyrosine and also mediated tyrosine phosphorylation of casein. Purified hek was subjected to N-terminal amino acid sequence analysis which showed that hek had a unique N terminus. Amino acid sequence determination of peptides from a V8 protease digest of hek yielded one 21-amino acid stretch of sequence which showed close homology with the eph subfamily of protein tyrosine kinases. These studies show hek to be a novel human tumor-associated protein tyrosine kinase, which by analogy with previously characterized protein tyrosine kinase proto-oncogenes, may have a role in tumorigenesis.

DrugBank Data that Cites this Article

Polypeptides
NameUniProt ID
Ephrin type-A receptor 3P29320Details