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Complexity of expression from transiently transfected plasmids

ABSTRACT: Transient plasmid transfection is common approach for studies in cultured mammalian cells. To examine behavior of transfected plasmids, we analyzed their transcriptional landscape by deep sequencing. We found that plasmids generate different levels of transcripts virtually everywhere. Spurious transcription may have undesirable effects as some co-transfected plasmids inhibited expression of luciferase reporters in a dose-dependent manner. In one case, we attributed this effect to kan/neo resistance cassette, which generated a unique population of edited sense and antisense small RNAs. The unexpected complexity of expression of transiently transfected plasmids highlights the importance of appropriate experimental controls. HEK293 cells (human origin) transiently transfected with 4 various plasmids

ORGANISM(S): Homo sapiens

SUBMITTER: Radek Malik

PROVIDER: E-GEOD-36062 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Deep sequencing reveals complex spurious transcription from transiently transfected plasmids.

Nejepinska Jana J Malik Radek R Moravec Martin M Svoboda Petr P

PloS one 20120816 8

Transient plasmid transfection is a common approach in studies in cultured mammalian cells. To examine behavior of transfected plasmids, we analyzed their transcriptional landscape by deep sequencing. We have found that the entire plasmid sequence is transcribed at different levels. Spurious transcription may have undesirable effects as some plasmids, when co-transfected, inhibited expression of luciferase reporters in a dose-dependent manner. In one case, we attributed this effect to a Kan/Neo ...[more]

PMID: 22916237

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