Human transferrin receptor: Expression of the receptor is assigned to chromosome 3

Human chromosome 3 has been identified as responsible for expression of the transferrin receptor in mouse-human lymphocyte hybrids. The receptor was detected by immunoprecipitation with anti-human receptor antibody of ¹²⁵I-labeled cells. This method also detected a similar 94,000-dalton protein in mouse cells. A radioimmunoassay developed for the human transferrin receptor measured 10% crossreactivity with the mouse protein. The two proteins were distinguished by NaDodSo₄/polyacrylamide gel patterns of partial proteolytic digests of the immunoprecipitated proteins. Mouse-human hybrids were generated by fusing a mouse thymoma (BW5147) cell line to either concanavalin A- or pokeweed mitogen-activated human peripheral blood lymphocytes or a mouse myeloma (NS-1) to uncultured human peripheral blood lymphocytes. Each hybrid was karyotyped with respect to both mouse and human chromosomes. In every case, expression of the human transferrin receptor correlated only with human chromosome 3.