Cloning and sequence determination of the gene for the human immunoglobulin epsilon chain expressed in a myeloma cell line.

Abstract

MRNA was isolated from cells of the human myeloma line 266BL which synthesizes IgE of the myeloma ND. A fraction enriched in mRNA for the .epsilon. H chain was copied into DNA and the DNA was cloned in Escherichia coli. A chemically synthesized oligonucleotide probe, based on the experimentally determined sequence of the specific message, was used to screen colonies. The largest .epsilon. chain c[complementary]DNA cloned, 2.0 kilobases, was characterized by restriction endonuclease mapping and DNA sequence analysis. It appears to encode the complete amino acid sequence of the .epsilon. chain, including a signal peptide at the NH2 terminus as well as untranslated sequences at the 5'' and 3'' ends of the mRNA. The missing part of the previously published amino acid sequence of the ND .epsilon. chain was determined from the DNA sequence.