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Keratin Transgenic and Knockout Mice

Functional Analysis and Validation of Disease-Causing Mutations
  • Preethi Vijayaraj
  • Goran Söhl
  • Thomas M. Magin
Part of the Methods in Molecular Biology™ book series (MIMB, volume 360)

Summary The intermediate filament (IF) cytoskeleton of mammalian epithelia is generated from pairs of type I and type II keratins that are encoded by two large gene families, made up of 54 genes in humans and the mouse. These genes are expressed in a spatiotemporal and tissue-specific manner from the blastocyst stage onward. Since the discovery of keratin mutations leading to epidermolysis bullosa simplex, mutations in at least 18 keratin genes have been identified that result in keratinopathies of the epidermis and its appendages. Recently, noncanonical mutations in simple epithelial keratins were associated with pancreatic, liver, and intestinal disorders, demonstrating that keratins protect epithelia against mechanical and other forms of stress. In recent years, animal models provided novel insight and significantly improved understanding of IF function in tissue homeostasis and its role in disease. Pathological phenotypes detected in mutant mice generated so far range from embryonic lethality to tissue fragility to subtlety, which often depends on their genetic background. This range implies at least a partial influence of yet unidentified modifier genes on the phenotype after the ablation of the respective keratin. To date, nearly all available keratin mouse models were generated by taking advantage of conventional gene-targeting strategies. To reveal their cell type-specific functions and the mechanisms by which mutations lead to disease, it will be necessary to use conditional gene-targeting strategies and the introduction of point-mutated gene copies. Furthermore, conditional strategies offer the possibility to overcome embryonic or neonatal lethality in some of the keratin-deficient mice.

Key Words

Blastocysts injection Cre/LoxP system epidermolysis bullosa simplex (EBS) epidermolytic hyperkeratosis (EHK) pachyonychia congenita embryonic stem (ES) cell culture Flp/FRT system genomic cluster knockout intermediate filaments knockout mice tetraploids transgenic mice 

Notes

Acknowledgments

We thank Ursula Reuter, Silke Loch, and Claudia Wohlenberg for excellent technical assistance. Work by the authors was supported by the Deutsche Forschungsgemeinschaft, the Bundesministerium fr Bildung und Forschung, and the Thyssen foundation. We apologize to those colleagues whose work has not been cited because of space restrictions.

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Copyright information

© Humana Press Inc. 2007

Authors and Affiliations

  • Preethi Vijayaraj
    • 1
  • Goran Söhl
    • 1
  • Thomas M. Magin
    • 1
  1. 1.Institut für Physiologische Chemie, Abteilung für Zellbiochemie, Bonner Forum Biomedizin and LIMESUniversitätsklinikum BonnBonnGermany

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