STOCK Gt(ROSA)26Sor^{tm2(Casp1)Vnce} Casp1^tm1Sesh Casp4^del/J

Stock number: 032661
Product name: iCasp1
Research areas: Diabetes and Obesity Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

iCasp1 compound mutant mice carry knock-out alleles of the mouse Casp1 and Casp4 (Casp11) genes in addition to a loxP-flanked Stop cassette-Casp1 cDNA-IRES-GFP-cre reporter knocked into the Gt(ROSA)26Sor gene. Cre-mediated excision of the loxP-flanked Stop cassette enables tissue-specific expression of mouse Casp1 cDNA and EGFP reporter. These mice have been useful in studies of bacterial pathogenesis.

Detailed description

Casp1 (caspase 1) mediates NLRC4 (NLR family, CARD domain containing 4)-induced pyroptosis and cytokine processing in macrophages.

These iCasp1 compound mutant mice carry a targeted knock-out allele of the mouse Casp1 (caspase 1) and Casp4 (caspase 4, apoptosis-related cysteine peptidase; also called Casp11) genes in addition to a loxP-flanked Stop cassette-Casp1 cDNA-IRES-GFP-cre reporter knocked into the Gt(ROSA)26Sor gene.

Cre-mediated excision of the loxP-flanked Stop cassette enables tissue-specific expression of mouse Casp1 cDNA and EGFP reporter in the presence of the Casp4 (Casp11) knock-out.

Crosses with Vil1-cre mice (see Stock No. 004586) or Lyz2-cre (see Stock No. 004781) have been used to demonstrate that Casp1 is required for intestinal epithelial cell pyroptosis but not expulsion in a model of Salmonella infection.

Development

A loxP-flanked transcriptional Stop cassette (in reverse transcriptional orientation) upstream of the mouse Casp1 cDNA and IRES-EGFP were introduced to the Gt(ROSA)26Sor gene via homologous recombination in C57BL/6NTac-derived JM8.F6 embryonic stem (ES) cells.

Resultant mice were intercrossed with mice expressing Casp1^tm1Sesh backcrossed to C57BL/6J for an unknown number of generations. This Casp1 knock-out allele (involving a neomycin cassette insertion in intron 6) was made in 129S2/SvPas-derived D3 embryonic stem (ES) cells carrying the truncated Casp4^del allele (also called Casp11^129mt or Casp11^-) that fails to produce functional CASP4. Casp4^del involves a 5 bp deletion in exon 7 that results in the fusion of exons 6 and 8, a frameshift after proline 304, and a stop codon after 5 aberrant amino acids.

Allele

Symbol: Casp4^del
Name: deletion
MGI accession ID: MGI:5473345
Generation method: Spontaneous
Attributes: Null/Knockout
Synonyms: Casp¹²⁹
Marker symbol: Casp4
Marker name: caspase 4, apoptosis-related cysteine peptidase
Marker synonyms: Casp11; CASP-4; Caspase-11; ICE(rel)II; ICE(rel)III; ICEREL-II; ICEREL-III; ICH-2; ich-3; Mih1; Mih1/TX; TX
Chromosome: 9
Strain of origin: 129P3/J and 129S1/SvImJ and 129S2/SvPas and 129S6/SvEvTac and 129X1/SvJ
Molecular note: RT-PCR confirmed that five 129 substrains (129X1/SvJ, 129S1/SvImJ, 129S2/SvPas, 129S6/SvEvTac and 129P3/J) express a transcript that lacks exon 7 (delta110 isoform). Sequencing identified a 5 bp deletion in exon 7 that results in the fusion of exon 6 and 8, a frame-shift after proline 304 and a stop codon after 5 aberrant amino acids. This deletion is not present in C57BL/6. Western blot analysis confirmed the absence of protein expression in LPS-primed macrophage.

Allele

Symbol: Gt(ROSA)26Sor^{tm2(Casp1)Vnce}
Name: targeted mutation 2, Russell E Vance
MGI accession ID: MGI:6246543
Generation method: Targeted
Attributes: Reporter; Inserted expressed sequence
Synonyms: iCasp1; Gt(ROSA)26Sor^{tm1(Casp1)Vnce}
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Marker synonyms: beta geo; Gtrgeo26; Gtrosa26; R26; ROSA26; SETD5-AS1; Thumpd3as1
Chromosome: 6
Strain of origin: C57BL/6N
Molecular note: The targeting vector includes a loxP-flanked transcriptional Stop cassette (in reverse transcriptional orientation) followed by mouse Casp1 cDNA and IRES-EGFP is introduced into the Gt(ROSA)26Sor gene via homologous recombination.

Allele

Symbol: Casp1^tm1Sesh
Name: targeted mutation 1, Tara Seshadri
MGI accession ID: MGI:1927822
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: Casp1 -; casp-1^-; Casp1^-/Casp11^129mt; Caspase-1-; ICE -
Marker symbol: Casp1
Marker name: caspase 1
Marker synonyms: Caspase-1; ICE; Il1bc; interleukin 1 beta-converting enzyme; p45
Chromosome: 9
Strain of origin: 129S2/SvPas
Molecular note: A neomycin expression cassette was inserted into exon 6, deleting 31 bp of sequence encoding the region of the active site and rendering the sequence out of frame after the insertion. Northern blot analysis on spleen RNA demonstrated an absence of the normal transcript in homozygous mice, and western blot analysis showed that the protein was not expressed in peritoneal macrophages of homozygous mice. This allele was generated in ES cells that lack protein expression of Casp11 (Casp^129mt).
General note: The ES cells used to generate this allele contain the linked Casp4^del truncated allele that fails to produce a functional Casp4. Phenotypes associated with this allele may be affected by the presence of the Casp^del allele. J:193522