Rearranged MOPC41 immunoglobulin κ gene constructs have been stably introduced into cultured S194 mouse plasmacytoma cells to investigate the effects of deleting the intronic enhancer and/or matrix association region (MAR) on gene expression. Intact single-copy κ genes containing 1.5 kilobase pairs of upstream and 8.5 kilobase pairs of downstream flanking sequences exhibited sensitivity to chromosome position effects and were expressed at a mean level of 27% relative to the endogenous κ gene expression or only 6% with respect to the MOPC41 κ mRNA levels in the tumor. Deletion of the intronic MAR led to a 4-fold decrease in expression, while deletion of both the MAR and enhancer led to an 11-fold decline. These effects were dampened by preselecting for integration into a transcriptionally poised chromatin location as demonstrated by linkage to a selectable marker which lacked both a MAR and an enhancer. Significantly, we found that sequences downstream of the poly(A) addition site compensated 150-fold for deletion of the intronic enhancer.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of Biological Chemistry|
|State||Published - 1989|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology