Cloning and expression of the cDNA coding for a human lymphocyte IgE receptor.
Low-affinity receptors (Fc epsilon R) and secreted factors (IgE-BF) which bind to immunoglobulins of the IgE isotype play a key role in the regulation of human IgE synthesis. We report here the cloning of a cDNA coding for the Fc epsilon R of the human B-lymphoblast cell line RPMI 8866. The nucleotide sequence of this cDNA predicts a polypeptide with 321 amino acids and a mol. wt of 36,281 daltons. A functional Fc epsilon R capable of binding IgE was expressed in Chinese hamster ovary cells after stable transformation with the cDNA which had been cloned into a mammalian expression vector. Amino acid sequence analysis of IgE-BF purified from RPMI 8866 cells revealed an amino-terminal sequence of 19 residues which coincides with the predicted amino acid sequence of the Fc epsilon R, starting at residues 148 and 150. A computer search with the translated amino acid sequence of the Fc epsilon R revealed a domain of 120 amino acids having striking homology to the human asialoglycoprotein receptors.
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism*; D004262:DNA Restriction Enzymes; D005796:Genes; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology*; D009710:Nucleotide Mapping; D011961:Receptors, Fc / Q000235:genetics* / Q000378:metabolism; D017455:Receptors, IgE; D011971:Receptors, Immunologic / Q000235:genetics* / Q000378:metabolism
D011961:Receptors, Fc; D017455:Receptors, IgE; D011971:Receptors, Immunologic; D007073:Immunoglobulin E; D004247:DNA; D004262:DNA Restriction Enzymes