The Chicken Lysozyme 5′ Matrix Attachment Region Increases Transcription from a Heterologous Promoter in Heterologous Cells and Dampens Position Effects on the Expression of Transfected Genes
Year: 1990
Type: article
Abstract: Matrix attachment regions (MARs) are DNA elements that dissect the genome into topologically separated domains by binding to a chromosomal skeleton. This study explored the putative influence of the MAR located 5' of the chicken lysozyme gene on expression of heterologous genes in heterologous cell systems. Expression of a construct with the chloramphenicol acetyltransferase (CAT) indicator gene controlled by the herpes simplex virus thymidine kinase promoter (TC) and a construct in which the same transcriptional unit is flanked by chicken lysozyme 5' MARs (MTCM) was assayed after stable transfection into rat fibroblasts. Median CAT activity per copy number in MTCM transfectants was elevated approximately 10-fold relative to that in TC transfectants. Total variation in normalized CAT activity decreased from more than 100-fold among TC transfectants to nearly 6-fold among MTCM transfectants. The steady-state level of transcripts and the relative rate of transcription were increased in MTCM transfectants, as shown by S1 nuclease and run-on transcription assays, respectively. The chicken lysozyme 5' MAR thus can confer elevated, less position-dependent expression on a heterologous promoter in cells of a different species by increasing the density of transcribing RNA polymerase molecules. MAR-mediated transcriptional enhancement suggests that MARs are important for gene expression and not just for DNA packaging.
Source: Molecular and Cellular Biology
Authors: L Phi-Van, J P von Kries, W Ostertag, W H Strätling
Institution: University Medical Center Hamburg-Eppendorf
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
Funder: Deutsche Forschungsgemeinschaft
OpenAlex ID: W1822511846