STOCK Col1a1^{tm1c(EUCOMM)Wtsi}/RklJ

Stock number: 037657
Product name: Col1a1^loxP
Research areas: Cancer Research, Developmental Biology Research, Internal/Organ Research, Research Tools

Description

Col1a1^loxP mice possess loxP sites flanking exons 2-5 of the collagen, type I, alpha 1 (Col1a1) gene. These mice may be useful for generating conditional mutants to evaluate the role of type 1 collagen in cre-expressing tissues.

Detailed description

Collagens are a family of structural proteins that are found in bones, cartilage, tendons, and skin; the most abundant being type I collagen (COL1). Typically, COL1 consists of two chains of collagen type I alpha 1 (encoded by Col1a1) and one chain of collagen type I alpha 2 (encoded by Col1a2). Systemic deletion of the Col1a1 gene results in embryonic lethality. In pathogenic conditions, such as organ fibrosis and cancer, there is excess accumulation of COL1 in the affected tissues and mutations in Col1a1 have been implicated in diseases such as osteogenesis imperfecta (OI) and osteoporosis.

Mice that are homozygous for this Col1a1^loxP floxed allele are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exons 2-5 deleted in the cre-expressing tissues. These Col1a1^loxP mice may be useful for studying the role of Col1a1 in multiple diseases.

Development

C57BL/6N-derived JM8A3.N1 embryonic stem (ES) cells (clone EPD0697_4_A06) bearing the Col1a1^{tm1a(EUCOMM)Wtsi} targeted allele were obtained from The European Conditional Mouse Mutagenesis Program (EUCOMM). The targeting cassette is composed of an FRT site followed by lacZ sequence and an initial loxP site upstream of exon 2 of the collagen, type I, alpha 1 (Col1a1) gene. This first loxP site is followed by a neomycin resistance gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site is inserted downstream of exon 5. Targeted ES cells were injected into recipient blastocysts. The resulting chimeric mice were bred with mice expressing Flp recombinase (B6.129S4-Gt(ROSA)26^{Sortm1(FLP1)Dym}/RainJ ; Stock No. 009086) to excise the FRT site-flanked lacZ and neo cassette. The Flp-expressing transgene was removed through selective breeding. The resulting Col1a1^loxP mice, with neo cassette removed and floxed exons 2-5 intact, were backcrossed for one generation to C57BL/6J mice. After which these mice were maintained on a mixed genetic background of C57BL/6, 129 and BALB/c by intercrossing homozygous Col1a1^loxP mice. 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: Col1a1^{tm1c(EUCOMM)Wtsi}
Name: targeted mutation 1c, Wellcome Trust Sanger Institute
MGI accession ID: MGI:6870533
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Synonyms: Col1a1^loxP
Marker symbol: Col1a1
Marker name: collagen, type I, alpha 1
Marker synonyms: CAFYD; Col1a-1; Cola1; Cola-1; COLIA1; EDSARTH1; EDSC; Mov-13; OI1; OI2; OI3; OI4
Chromosome: 11
Strain of origin: C57BL/6N-A^tm1Brd
Molecular note: The L1L2_Bact_P cassette was inserted at position 94828245 of Chromosome 11 upstream of the critical exon(s) (Build GRCm39). The cassette is composed of an FRT site followed by lacZ sequence and a loxP site. This first loxP site is followed by a neomycin resistance gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site is inserted downstream of the targeted exon(s) at position 94829703. The critical exon(s) is/are thus flanked by loxP sites. A "conditional ready" (floxed) allele was created by flp recombinase expression in mice carrying this allele to remove the lacZ sequence and neo selection cassette, leaving loxP sites flanking the critical exon(s). Further information on targeting strategies used for this and other IKMC alleles can be found at http://www.informatics.jax.org/mgihome/nomen/IKMC_schematics.shtml