Induction of immunoglobulin gene expression in mouse fibroblasts by cycloheximide treatment

A complete set of a rearranged human gamma 1-heavy chain gene, HIG1, was cloned from human plasma cell leukemia line, ARH-77, and transferred into mouse cells. It was strongly expressed in mouse myeloma cells but not in mouse L cells, indicating that immunoglobulin gene expression is not species-specific but cell-specific. However, a remarkable production of human gamma 1 chain was induced in mouse L cells containing HIG1 gene when the cells were treated with cycloheximide for a short period. The role of a labile repressor molecule in the expression of the immunoglobulin gene is proposed.