STOCK Casp4^del Tg(CASP4)1Bux/J

Stock number: 037900
Product name: Casp11 KO; huCASP4 Tg
Strain synonyms: Casp4 KO; huCASP4 Tg
Research areas: Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

Casp11 KO; huCASP4 Tg mice lack mouse Casp4 (Casp11) and express human CASP4. When treated with LPS, mutant mice developed an enhanced endotoxin sensitivity. These mice maybe useful for research involving human endotoxin responses.

Detailed description

CASP4 (caspase 4, formerly Casp11) encodes an inflammatory caspase involved in cell apoptosis and in controlling inflammatory responses through the secretion of IL1B and IL18. CASP4 also is a component of the inflammasome and involved in activating CASP1. Inflammatory caspases, Casp1 and Casp11, are also involved in regulation of IL1B secretion and endotoxin response.

The Casp4^del null allele [Casp11 KO] is present in five 129 substrains including 129S2/SvPas. The del allele has a 5 bp deletion in exon 7 of Casp4 resulting in a frameshift; no CASP4 protein is expressed.

CASP4 transgenic mice express the human CASP4 gene (BAC RP11 693N9; Tg(CASP4)1Bux). CASP4 is not present in the mouse genome. CASP4 is constitutively expressed in lymphoid tissues including spleen and thymus, as well as intestine and lung. CASP4 has weak expression in the brain. Tg(CASP4)1Bux homozygotes are viable and fertile. When treated with a sublethal dose of LPS, all transgenic mice die within 24 hours exhibiting an enhanced endotoxin sensitivity.

Mice homozygous for the Casp4^del null allele [Casp11 KO] and hemizygous for the human CASP4 transgene [Tg(CASP4)1Bux] are viable and fertile.

Development

Mice carrying Casp4^del and Tg(CASP4)1Bux were combined to generate this strain.

The Casp4^del allele is naturally present in five 129 substrains including 129S2/SvPas. The del allele has a 5 bp deletion in exon 7 of Casp4 resulting in a frameshift after proline 304 and a stop codon after 5 aberrant amino acids; no mouse CASP4 protein is expressed.

The human CASP4 transgenic construct contains the entire human CASP4 gene and 6.8 kb of upstream sequences including the promoter region (bacterial artificial chromosome clone, RP11 693N9). The BAC clone also includes the long isoform of CASP12 (carrying a single nucleotide variant found in a small proportion of humans with African ancestry). The long isoform is catalytically inactive but acts to suppress LPS-induced cytokine secretion and NFKB activation. The BAC was microinjected into the pronuclei of fertilized C57BL/6 x C3 (B6C3) hybrid oocytes. The donating laboratory reports transgenic founder line 1 [Tg(CASP4)1Bux] was bred to C57BL/6J mice for at least 6 generations, and then bred to a 129 substrain harboring the Casp4^del allele (see SNP results below).

Upon arrival at The Jackson Laboratory Repository in 2023, sperm was cryopreserved (homozygous for Casp4^del, hemizygous for Tg(CASP4)1Bux). To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

In 2023, a 48 SNP (single nucleotide polymorphism) panel analysis, with 43 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the males sent to The Jackson Laboratory Repository. This revealed a total of 4 markers that were not fixed for C57BL/6 allele-type (1 marker on chromosome 4, 11, 17 and 19 was segregating for C57BL/6 and C3H/129S allele-type). These data suggest that the mice sent to The Jackson Laboratory Repository were not completely backcrossed to C57BL/6J, and may be ~80-85% C57BL/6 with ~15-20% contributions from C3H, 129S and/or other genetic backgrounds.

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: Tg(CASP4)1Bux
Name: transgene insertion 1, Joseph Buxbaum
MGI accession ID: MGI:7433250
Generation method: Transgenic
Attributes: Inserted expressed sequence; Humanized sequence
Marker symbol: Tg(CASP4)1Bux
Marker name: transgene insertion 1, Joseph Buxbaum
Chromosome: UN
Strain of origin: C57BL/6 x C3
Molecular note: The human CASP4 transgenic construct contains the entire human CASP4 gene and 6.8 kb of upstream sequences including the promoter region (bacterial artificial chromosome clone, RP11 693N9). The BAC clone also includes the long isoform of CASP12 (carrying a single nucleotide variant found in a small proportion of humans with African ancestry). The long isoform is catalytically inactive but acts to suppress LPS-induced cytokine secretion and NFKB activation.