Targeted Mutagenesis in the Immune System


Mice with defined mutations in any known gene can be created by homologous recombination in embryonic stem cells. The genetic approach is instrumental in delineating the mechanisms that control leucocyte development and immune response.

Keywords: immunology; gene targeting; Cre‐loxP; homologous recombination; embryonic stem cells

Figure 1.

Gene targeting by homologous recombination in mouse embryonic stem (ES) cells. The successive stages of the procedures are indicated (see text for details).

Figure 2.

Conditional mutagenesis in mice using the Cre‐loxP system. Top: Introduction of loxP sites into a chromosomal gene by homologous recombination in embryonic stem (ES) cells. Middle: Removal of the resistance marker from the targeted locus by Cre‐mediated recombination in ES cells to create a modified locus containing only the two loxP sites required for conditional mutagenesis. Bottom: Cell‐type specific gene inactivation in vivo by Cre‐mediated recombination of the floxed locus. Animals carrying the floxed locus are mated with transgenic or ‘Cre knock‐in’ mice expressing Cre in the target tissue. Gene inactivation by Cre‐mediated exon deletion occurs only in the target tissue.



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Further Reading

Biomednet. Mouse Knockout Database. [ ]

Induced Mutation Database ‘Tbase’. [ ]

Mouse Genome Informatics Project. [ ]

Torres R, Kühn R and Rajewsky K (1997) Laboratory Protocols for Conditional Gene Targeting. Oxford: Oxford University Press.

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How to Cite close
Roes, Jürgen(Mar 2002) Targeted Mutagenesis in the Immune System. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0001182]