Gene trapping

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Gene trapping is a high-throughput approach that is used to introduce insertional mutations across an organism's genome.

Contents

Method

Trapping is performed with gene trap vectors whose principal element is a gene trapping cassette consisting of a promoterless reporter gene and/or selectable genetic marker, flanked by an upstream 3' splice site (splice acceptor; SA) and a downstream transcriptional termination sequence (polyadenylation sequence; polyA).

When inserted into an intron of an expressed gene, the gene trap cassette is transcribed from the endogenous promoter of that gene in the form of a fusion transcript in which the exon(s) upstream of the insertion site is spliced in frame to the reporter/selectable marker gene. Since transcription is terminated prematurely at the inserted polyadenylation site, the processed fusion transcript encodes a truncated and nonfunctional version of the cellular protein and the reporter/selectable marker. Thus, gene traps simultaneously inactivate and report the expression of the trapped gene at the insertion site, and provide a DNA tag (gene trap sequence tag, GTST) for the rapid identification of the disrupted gene. [1] [2]

Access

The International Gene Trap Consortium is centralizing the data and supplies modified cell lines. [3]

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References

  1. Cobellis, G; Nicolaus, G; et al. (2005). "Tagging genes with cassette-exchange sites". Nucleic Acids Res. 33 (4): e44. doi:10.1093/nar/gni045. PMC   552971 . PMID   15741177.
  2. De-Zolt, S; Schnutgen, F; et al. (2006). "High-throughput trapping of secretory pathway genes in mouse embryonic stem cells". Nucleic Acids Res. 34 (3): 25. doi:10.1093/nar/gnj026. PMC   1369290 . PMID   16478711.
  3. "IGTC, International Gene Trap Consortium". www.genetrap.org. Retrieved 2018-02-11.

Further reading