Zp3-cre, a transgenic mouse line for the activation or inactivation of loxP-flanked target genes specifically in the female germ line.
The site-specific DNA recombinase Cre is being used to develop a new generation of tools for controlling gene expression in mice [1]. Cre mediates the recombination of two directly repeated target (loxP) sites to a single loxP site, with concomitant excision of the DNA segment flanked by the loxP sites (the 'floxed' DNA). Such recombination can function to activate a gene by excising a floxed DNA segment that blocks expression because it either separates the regulatory and coding sequences of the gene [2] or interrupts the gene's open reading frame. Conversely, DNA excision can inactivate a gene if an essential fragment of the gene is floxed [3]. Gene activation or inactivation in vivo can be achieved by mating two different animals, one carrying a 'target gene' with appropriately placed loxP sites and one carrying a cre transgene. In most cases, the specificity of the system is dependent upon stringent regulation of cre expression. We describe here a mouse line in which cre expression is controlled by regulatory sequences from the mouse zona pellucida 3 (Zp3) gene, which is normally expressed exclusively in the growing oocyte prior to the completion of the first meiotic division [4]. We show that in target-bearing Zp3-cre mice, Cre-mediated recombination of the target gene apparently occurs in 100 % of oocytes. Moreover, Cre activity is not detected in the somatic tissues of most target-bearing Zp3-cre mice. Potential uses for this mouse line are discussed.
Lewandoski
M
M
Department of Anatomy and Program in Developmental Biology, School of Medicine, University of California, San Francisco, California 94143-0452, USA.
Wassarman
K M
KM
Martin
G R
GR
D000818:Animals; D001483:Base Sequence; D003433:Crosses, Genetic; D017931:DNA Primers; D004527:Egg Proteins / Q000096:biosynthesis / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D019426:Integrases / Q000096:biosynthesis* / Q000235:genetics; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D008822:Mice, Transgenic; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D011956:Receptors, Cell Surface; D011995:Recombination, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D012091:Repetitive Sequences, Nucleic Acid; D012727:Sex Characteristics; D015533:Transcriptional Activation; D014764:Viral Proteins; D015044:Zona Pellucida / Q000502:physiology*; D000072216:Zona Pellucida Glycoproteins
D017931:DNA Primers; D004527:Egg Proteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D014764:Viral Proteins; D000072216:Zona Pellucida Glycoproteins; C000606521:Zp3 protein, mouse; C045073:Cre recombinase; D019426:Integrases