C57BL/6J-Il1a^em1Tdk/J

Stock number: 037967
Product name: Il1a-KO^line2
Strain synonyms: Il1a^-
Research areas: Cancer Research, Immunology, Inflammation and Autoimmunity Research

Description

The Il1a KO^{line 2} mice have a CRISPR/Cas9 generated deletion of exons 2-6 of the interleukin 1 alpha (Il1a) gene. These mice may be useful when studying inflammatory pathways, hematopoiesis and immunity.

Detailed description

Interleukin 1 alpha (encoded by the Il1a gene) is a dual-function cytokine involved with inflammation, immune response and hematopoiesis. Using CRISPR/Cas9-mediated genome editing, exons 2-6 of the Il1a gene were deleted in this Il1a knock-out model.

Homozygous Il1a KO^{line 2} mice are viable and fertile with no overt phenotype. The donating laboratory indicates that bone marrow-derived macrophages from these mice are deficient in IL-1α but still demonstrate normal IL-1β production; this is in contrast to the Il1a^tm1Yiw allele (Il1a KO^line1) which has been found to have a significant reduction in IL-1β production as well as IL-1α expression. Il1a KO^{line 2} mice have white blood cell counts similar to wildtype mice and no defects in expression or activation of inflammasome components in response to pathogens. Due to the deficiency of IL-1α, these mice do have decreased expression of the neutrophil chemoattractant KC/CXCL1 in response to innate immune triggers. These mice may be useful for studying the regulatory role of Il1a in autoinflammatory diseases and cancers.

Development

The Il1a KO^line2 allele was generated using CRISPR/Cas9 endonuclease-mediated genome editing. Guide RNAs [AAAAGCTTCTGACGTACCACagg and AAGTAACAGCGGAGCGCTTTtgg, PAM sequences indicated by lowercase letters] were selected to delete exons 2 to 6 of the interleukin 1 alpha gene (Il1a) on Chromosome 2. Il1a transcript from Mus musculus interleukin 1 alpha (Il1a); NCBI Reference Sequence: NM_010554.4, was used as reference for the exon numbering and the guide/donor sequences. These sequences and Cas9 nuclease were introduced into C57BL/6J zygotes and transferred to pseudopregnant CD1 females. Correctly targeted pups were identified by PCR and Sanger sequencing. The resulting heterozygous Il1a KO^line2 mice were bred to C57BL/6J mice for 3 generations to reduce off-target CRISPR events. Upon arrival at The Jackson Laboratory, 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: Il1a^em1Tdk
Name: endonuclease-mediated mutation 1, Thirumala-Devi Kanneganti
MGI accession ID: MGI:7431279
Generation method: Endonuclease-mediated
Attributes: Null/Knockout
Synonyms: Il1a-KO^line2
Marker symbol: Il1a
Marker name: interleukin 1 alpha
Marker synonyms: IL1; IL-1 alpha; Il-1a; IL1-ALPHA; IL1F1; IL-1F1
Chromosome: 2
Strain of origin: Not Applicable
Molecular note: CRISPR/cas9 genome editing uses guide RNAs (AAAAGCTTCTGACGTACCACagg and AAGTAACAGCGGAGCGCTTTtgg, PAM sequences indicated by lowercase letters) to delete exons 2 to 6. Il1a transcript from Mus musculus interleukin 1 alpha (Il1a); NCBI Reference Sequence: NM_010554.4, was used as reference for the exon numbering and the guide/donor sequences.