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. 1992 Jul 1;176(1):233–243. doi: 10.1084/jem.176.1.233

Two unusual forms of human immunoglobulin E encoded by alternative RNA splicing of epsilon heavy chain membrane exons

PMCID: PMC2119292  PMID: 1613458

Abstract

We present evidence for RNA transcripts encoding two forms of human epsilon immunoglobulin (Ig) heavy chain that differ significantly from those of other isotypes. We previously demonstrated three human epsilon mRNA species, instead of the two, corresponding to membrane and secreted proteins, seen with other heavy chain transcripts. In human genomic DNA downstream of the C epsilon gene, we identified sequences homologous to the two putative murine exons M1 (encoding a hydrophobic, presumably transmembrane region) and M2 (encoding hydrophilic residues). To determine the structures of epsilon transcripts containing these sequences, we amplified epsilon-related RNAs with the reverse transcriptase polymerase chain reaction. RNA was examined from fresh human B cells stimulated to IgE production by interleukin 4 plus anti-CD40, as well as from the human IgE-producing line AF10. Instead of the single CH4-M1-M2 splice product predicted for murine membrane IgE, we found two other RNA species. One form has the structure CH4-M1'- M2, in which M1' includes the human sequence homologous to the murine M1 as well as a unique segment of 52 codons further upstream in the genomic sequence; this RNA species apparently encodes the IgE expressed on the membrane of IgE-producing lymphocytes. The other RNA has the structure CH4-M2', in which M2' is spliced in an alternative reading frame that includes an additional 109 codons downstream of the termination codon of the CH4-M1'-M2 form. Because the CH4-M2' mRNA form does not encode a hydrophobic segment, its translated product should be secreted. A secreted epsilon protein of approximately the size predicted for this form was identified by Western blotting. This novel IgE protein could play a significant and distinctive role in allergic disorders.

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Selected References

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  1. Bennich H., Johansson S. G. Structure and function of human immunoglobulin E. Adv Immunol. 1971;13:1–55. doi: 10.1016/s0065-2776(08)60182-0. [DOI] [PubMed] [Google Scholar]
  2. Bensmana M., Lefranc M. P. Gene segments encoding membrane domains of the human immunoglobulin gamma 3 and alpha chains. Immunogenetics. 1990;32(5):321–330. doi: 10.1007/BF00211646. [DOI] [PubMed] [Google Scholar]
  3. Boyd D., Beckwith J. The role of charged amino acids in the localization of secreted and membrane proteins. Cell. 1990 Sep 21;62(6):1031–1033. doi: 10.1016/0092-8674(90)90378-r. [DOI] [PubMed] [Google Scholar]
  4. Cambier J. C., Campbell K. S. Signal transduction by B lymphocyte receptors: structure-function relationships of membrane immunoglobulins and associated molecules. Semin Immunol. 1990 Mar;2(2):139–149. [PubMed] [Google Scholar]
  5. Cheng H. L., Blattner F. R., Fitzmaurice L., Mushinski J. F., Tucker P. W. Structure of genes for membrane and secreted murine IgD heavy chains. Nature. 1982 Apr 1;296(5856):410–415. doi: 10.1038/296410a0. [DOI] [PubMed] [Google Scholar]
  6. Early P., Rogers J., Davis M., Calame K., Bond M., Wall R., Hood L. Two mRNAs can be produced from a single immunoglobulin mu gene by alternative RNA processing pathways. Cell. 1980 Jun;20(2):313–319. doi: 10.1016/0092-8674(80)90617-0. [DOI] [PubMed] [Google Scholar]
  7. Early P., Rogers J., Davis M., Calame K., Bond M., Wall R., Hood L. Two mRNAs can be produced from a single immunoglobulin mu gene by alternative RNA processing pathways. Cell. 1980 Jun;20(2):313–319. doi: 10.1016/0092-8674(80)90617-0. [DOI] [PubMed] [Google Scholar]
  8. Flanagan J. G., Rabbitts T. H. Arrangement of human immunoglobulin heavy chain constant region genes implies evolutionary duplication of a segment containing gamma, epsilon and alpha genes. Nature. 1982 Dec 23;300(5894):709–713. doi: 10.1038/300709a0. [DOI] [PubMed] [Google Scholar]
  9. Hassner A., Saxon A. Isotype-specific human suppressor T cells for IgE synthesis activated by IgE-anti-IgE immune complexes. J Immunol. 1984 Jun;132(6):2844–2849. [PubMed] [Google Scholar]
  10. Ishida N., Ueda S., Hayashida H., Miyata T., Honjo T. The nucleotide sequence of the mouse immunoglobulin epsilon gene: comparison with the human epsilon gene sequence. EMBO J. 1982;1(9):1117–1123. doi: 10.1002/j.1460-2075.1982.tb01306.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Ishida N., Ueda S., Hayashida H., Miyata T., Honjo T. The nucleotide sequence of the mouse immunoglobulin epsilon gene: comparison with the human epsilon gene sequence. EMBO J. 1982;1(9):1117–1123. doi: 10.1002/j.1460-2075.1982.tb01306.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Ishizaka K., Ishizaka T., Hornbrook M. M. Physico-chemical properties of human reaginic antibody. IV. Presence of a unique immunoglobulin as a carrier of reaginic activity. J Immunol. 1966 Jul;97(1):75–85. [PubMed] [Google Scholar]
  13. Kinoshita K., Shimizu A., Honjo T. The membrane exons of the pseudo-gamma-chain gene of the human immunoglobulin are apparently functional and highly homologous to those of the gamma 1 gene. Immunol Lett. 1991 Feb;27(2):151–155. doi: 10.1016/0165-2478(91)90143-x. [DOI] [PubMed] [Google Scholar]
  14. Max E. E., Battey J., Ney R., Kirsch I. R., Leder P. Duplication and deletion in the human immunoglobulin epsilon genes. Cell. 1982 Jun;29(2):691–699. doi: 10.1016/0092-8674(82)90185-4. [DOI] [PubMed] [Google Scholar]
  15. Milstein C. P., Deverson E. V., Rabbitts T. H. The sequence of the human immunoglobulin mu-delta intron reveals possible vestigial switch segments. Nucleic Acids Res. 1984 Aug 24;12(16):6523–6535. doi: 10.1093/nar/12.16.6523. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Mitchell R. N., Shaw A. C., Weaver Y. K., Leder P., Abbas A. K. Cytoplasmic tail deletion converts membrane immunoglobulin to a phosphatidylinositol-linked form lacking signaling and efficient antigen internalization functions. J Biol Chem. 1991 May 15;266(14):8856–8860. [PubMed] [Google Scholar]
  17. Peng C., Davis F. M., Sun L. K., Liou R. S., Kim Y. W., Chang T. W. A new isoform of human membrane-bound IgE. J Immunol. 1992 Jan 1;148(1):129–136. [PubMed] [Google Scholar]
  18. Saxon A., Feldhaus J., Robins R. A. Single step separation of human T and B cells using AET treated srbc rosettes. J Immunol Methods. 1976;12(3-4):285–288. doi: 10.1016/0022-1759(76)90050-8. [DOI] [PubMed] [Google Scholar]
  19. Saxon A., Kurbe-Leamer M., Behle K., Max E. E., Zhang K. Inhibition of human IgE production via Fc epsilon R-II stimulation results from a decrease in the mRNA for secreted but not membrane epsilon H chains. J Immunol. 1991 Dec 1;147(11):4000–4006. [PubMed] [Google Scholar]
  20. Saxon A., Portis J. Lymphoid subpopulation changes in regional lymph nodes in squamous head and neck cancer. Cancer Res. 1977 Apr;37(4):1154–1158. [PubMed] [Google Scholar]
  21. Seif I., Khoury G., Dhar R. BKV splice sequences based on analysis of preferred donor and acceptor sites. Nucleic Acids Res. 1979 Jul 25;6(10):3387–3398. doi: 10.1093/nar/6.10.3387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Sun L. K., Liou R. S., Sun N. C., Gossett L. A., Sun C., Davis F. M., MacGlashan D. W., Jr, Chang T. W. Transfectomas expressing both secreted and membrane-bound forms of chimeric IgE with anti-viral specificity. J Immunol. 1991 Jan 1;146(1):199–205. [PubMed] [Google Scholar]
  23. White M. B., Shen A. L., Word C. J., Tucker P. W., Blattner F. R. Human immunoglobulin D: genomic sequence of the delta heavy chain. Science. 1985 May 10;228(4700):733–737. doi: 10.1126/science.3922054. [DOI] [PubMed] [Google Scholar]
  24. Word C. J., Mushinski J. F., Tucker P. W. The murine immunoglobulin alpha gene expresses multiple transcripts from a unique membrane exon. EMBO J. 1983;2(6):887–898. doi: 10.1002/j.1460-2075.1983.tb01518.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Yamawaki-Kataoka Y., Nakai S., Miyata T., Honjo T. Nucleotide sequences of gene segments encoding membrane domains of immunoglobulin gamma chains. Proc Natl Acad Sci U S A. 1982 Apr;79(8):2623–2627. doi: 10.1073/pnas.79.8.2623. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Yu L. M., Peng C., Starnes S. M., Liou R. S., Chang T. W. Two isoforms of human membrane-bound alpha Ig resulting from alternative mRNA splicing in the membrane segment. J Immunol. 1990 Dec 1;145(11):3932–3936. [PubMed] [Google Scholar]
  27. Yu L. M., Peng C., Starnes S. M., Liou R. S., Chang T. W. Two isoforms of human membrane-bound alpha Ig resulting from alternative mRNA splicing in the membrane segment. J Immunol. 1990 Dec 1;145(11):3932–3936. [PubMed] [Google Scholar]
  28. Zorn A. M., Krieg P. A. PCR analysis of alternative splicing pathways: identification of artifacts generated by heteroduplex formation. Biotechniques. 1991 Aug;11(2):180–184. [PubMed] [Google Scholar]

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