B6;129-Scgb1a1^tm2(icre)Fjd/J

Stock number: 036525
Product name: CCSP^icre
Research areas: Internal/Organ Research, Research Tools

Description

These CCSP^icre knock-in/knock-out mice contain an icre recombinase gene inserted upstream of the Scgb1a1 gene. This strain may useful for inducing efficient icre recombinase activity only in bronchiolar non-ciliated Clara cells.

Detailed description

These CCSP^icre knock-in/knock-out mice have an improved cre (icre) recombinase gene inserted upstream of the start codon of the secretoglobin, family 1A, member 1 (uteroglobin) (Scgb1a1) gene. icre activity is observed specifically in non-ciliated Clara cells in the trachea, the bronchi, and bronchioles. Homozygous mice are viable and fertile. When these mice are bred with mice containing loxP-flanked sequence, icre-mediated recombination will result in deletion of the floxed sequences in the cre-expressing cells of the offspring. icre activity is observed in the majority of airway epithelial cells including the trachea, the bronchi and bronchioles.

When bred to Pten floxed mice (Stock No. 006440), resulting Pten^d/d offspring, with airway-specific deletion of Pten, develop airway epithelial hyperplasia without progression to tumor.

Of note, Stock No. 016225 is a knock-in strain that expresses a tamoxifen-inducible form of cre recombinase from the ^Scgb1a1 locus, without disrupting the endogenous gene.

In November 2021, it was determined that the frt-flanked neo cassette was still present in the mice sent to The Jackson Laboratory. The donating investigator confirms that the presence of the neo does not interfere with pulmonary cre expression pattern.

Development

The CCSP^icre knock-in/knock-out targeting vector contains an improved cre (icre) recombinase gene sequence followed by SV40 PolyA and an inverted PGK-Neo-cassette flanked by frt sites upstream of the start codon of the secretoglobin, family 1A, member 1 (uteroglobin) (Scgb1a1) gene. The construct was electroporated into (129X1/SvJ x 129S1/Sv)F1-Kitl⁺-derived R1 embryonic stem (ES) cells and correctly targeted ES cells were injected into C57BL/6 blastocysts. Resulting chimeric animals were bred to a mutant strain containing a Gt(ROSA) knock-in allele on a B6;129 mixed genetic background for a few generations. Recently, the contaminating mutant allele was removed from the colony by breeding mice containing only the CCSP^icre allele to C57BL/6J mice for at least three generations. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Scgb1a1^tm2(icre)Fjd
Name: targeted mutation 2, Franco J DeMayo
MGI accession ID: MGI:5433101
Generation method: Targeted
Attributes: Recombinase-expressing
Synonyms: CCSP^iCre; Scgb1a1^tm1(icre)Eem; Scgb1a1-cre
Marker symbol: Scgb1a1
Marker name: secretoglobin, family 1A, member 1 (uteroglobin)
Marker synonyms: Blastokinin; CC10; CC16; CCPBP; CCSP; club cell secretory protein; PCBB; PCB-BP; UG; Ugb; UP1; UP-1; Utg
Chromosome: 19
Strain of origin: (129X1/SvJ x 129S1/Sv)F1-Kitl⁺
Site of expression: Improved cre (icre) recombinase activity is observed specifically in non-ciliated Clara cells in the trachea, the bronchi, and bronchioles. icre activity is observed in the majority of airway epithelial cells including the trachea, the bronchi and bronchioles.
Molecular note: The improved cre (icre) and FRT-flanked neomycin resistance cassette were inserted at the translation initation site. Activity was observed the majority of airway epithelial cells including the trachea, the bronchi and bronchioles.