Cell-type specific expression of a transfected immunoglobulin gene

Abstract

The introduction of cloned genes into eukaryotic cells has become a major technique in the study of gene expression. Many experiments have demonstrated transcription of cloned genes after transfection into heterologous cell systems—cells in which the genes are not normally active^1–4. More recently, several investigators have obtained expression of specialized genes after transfection into cells of the corresponding specialized type, notably the β-globin gene in erythroleukaemic cells⁵ and immunoglobulin genes in myeloma cells^6,7. These results allow the study of gene expression during development by comparing transcription of a gene transfected into homologous and heterologous cells. We have shown that a rearranged κ immunoglobulin gene, cloned from a mouse myeloma, is transcribed transiently at a high level when reintroduced into mouse myeloma cells⁸. We show here, in an internally controlled manner, that the same immunoglobulin gene is not detectably transcribed when transfected into mouse 3T3 or L cells.