Tissue-specific expression in mouse P815 mastocytoma cells of the cloned rat alpha-subunit gene of the high-affinity receptor for immunoglobulin E.
The high-affinity multisubunit receptor for IgE, Fc epsilon RI, is expressed in vivo in a tissue-specific manner, being found only on mast cells, basophils and epidermal Langerhans cells. The expression of the rat Fc epsilon RI alpha-subunit transcript has been examined here in the mouse mastocytoma cell line, P815, which does not express the endogenous mouse Fc epsilon RI alpha- or beta-subunit transcripts. These studies indicate that an exogenously introduced rat alpha-subunit gene can be faithfully expressed in P815 cells, while no transcripts are produced in the mouse or rat B-lymphoid cell lines, SP2/0 and IR162, respectively. Therefore, in contrast to both B-cell lines, factors necessary for the tissue-specific expression of the alpha-subunit mRNA are present in the P815 cell line, yielding a correctly processed mRNA transcript; nevertheless, this tissue-specific expression is not rigorously species specific. Although the mechanism responsible for these observations is unknown, these results do imply that a specific cis-trans element interaction occurs between this transcriptional unit and factors in the P815 cells that control fidelity of tissue-specific mRNA synthesis and processing from the Fc epsilon RI alpha-subunit gene. Consequently, this reconstructed rat Fc epsilon RI alpha-subunit gene contains minimally sufficient cis elements for tissue-specific expression of mRNA, and so, the P815 cell line should be useful to define these requisite DNA cis elements of the gene, as well as the trans factors from P815 necessary for this process.
Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock 79430, USA.
B A
BA
Witthuhn
C
C
Faust
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology*; D012515:Mast-Cell Sarcoma / Q000235:genetics* / Q000276:immunology*; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics / Q000276:immunology; D051381:Rats; D017455:Receptors, IgE / Q000096:biosynthesis / Q000235:genetics*; D014162:Transfection; D014407:Tumor Cells, Cultured
D017455:Receptors, IgE