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PubMed · 8011170

High-copy expression vector based on amplification-promoting sequences.

C Hemann·E Gärtner·U H Weidle·F Grummt
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Abstract

We describe a new vector system that allows efficient expression of heterologous proteins in transformed mouse L fibroblasts. This is due to its persistence at high copy numbers, achieved by a 370-bp amplification promoting element (muNTS1) derived from the nontranscribed spacer of murine rDNA. Copy number determination showed that this sequence mediates a 40- to 800-fold amplification of the vector DNA in transfected L cells. High copy number was accompanied by increased expression levels of the reporter gene secreted alkaline phosphatase (SEAP). Analyzing the structural organization of multicopy plasmid DNA in mouse L cells revealed that plasmid DNA is integrated as reiterated head-to-tail concatamers into the chromosomal DNA. The vector described here can be used as a versatile high-copy expression system for heterologous proteins overcoming any limitation to enzyme-deficient cell lines.

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Alkaline PhosphataseAnimalsDNA, RibosomalGene AmplificationGenes, ReporterGenetic VectorsL CellsMicePlasmidsThymidine KinaseTransfectionTransformation, GeneticJournal ArticleResearch Support, Non-U.S. Gov't

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C Hemann, E Gärtner, U H Weidle, F Grummt. 1994. High-copy expression vector based on amplification-promoting sequences.. https://doi.org/10.1089/dna.1994.13.437

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