Temporally-controlled Site-Specific Mutagenesis in the Basal Layer of the Epidermis: Comparison of the Recombinase Activity of the Tamoxifen-Inducible Cre-ER(T) and Cre-ER(T2) Recombinases

Nucleic Acids Res. 1999 Nov 15;27(22):4324-7. doi: 10.1093/nar/27.22.4324.

Abstract

Conditional DNA excision between two LoxP sites can be achieved in the mouse using Cre-ER(T), a fusion protein between a mutated ligand binding domain of the human estrogen receptor (ER) and the Cre recombinase, the activity of which can be induced by 4-hydroxy-tamoxifen (OHT), but not natural ER ligands. We have recently characterized a new ligand-dependent recombinase, Cre-ER(T2), which was approximately 4-fold more efficiently induced by OHT than Cre-ER(T) in cultured cells. In order to compare the in vivo efficiency of these two ligand-inducible recombinases to generate temporally-controlled somatic mutations, we have engineered transgenic mice expressing a LoxP-flanked (floxed) transgene reporter and either Cre-ER(T) or Cre-ER(T2) under the control of the bovine keratin 5 promoter that is specifically active in the epidermis basal cell layer. No background recombinase activity could be detected, while recombination was induced in basal keratinocytes upon OHT administration. Interestingly, a dose-response study showed that Cre-ER(T2) was approximately 10-fold more sensitive to OHT induction than Cre-ER(T).

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Enzyme Induction
  • Epidermis / drug effects
  • Epidermis / enzymology*
  • Estrogen Receptor Modulators / pharmacology*
  • Genes, Reporter
  • Humans
  • Integrases / biosynthesis*
  • Integrases / genetics
  • Integrases / metabolism
  • Keratinocytes / drug effects
  • Keratinocytes / physiology
  • Mice
  • Mice, Transgenic
  • Mutagenesis, Site-Directed
  • Receptors, Estrogen / antagonists & inhibitors
  • Receptors, Estrogen / genetics
  • Receptors, Estrogen / metabolism
  • Recombinant Fusion Proteins / drug effects
  • Recombinant Fusion Proteins / metabolism
  • Tamoxifen / analogs & derivatives*
  • Tamoxifen / pharmacology
  • Viral Proteins*

Substances

  • Estrogen Receptor Modulators
  • Receptors, Estrogen
  • Recombinant Fusion Proteins
  • Viral Proteins
  • Tamoxifen
  • afimoxifene
  • Cre recombinase
  • Integrases