STOCK Ptprc^a Pepc^b Pkm^tm1.1Mgvh/J

Stock number: 030113
Product name: Pkm2^fl on B6 Cd45.1, Pep Boy
Research areas: Cancer Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

These mutant mice are homozygous for the Ptprc^a, Pepc^b, and Pkm^tm1.1Mgvh alleles. When crossed to a Cre recombinase expressing strain, resulting offspring will have loxP site flanked exon 10 of the Pkm gene deleted in the cre expressing tissues. This strain is useful in transplantation studies related to as the Ptprc^a pan leukocyte marker commonly known as CD45.1 or Ly5.1 allows tracking of transplanted hematopoietic cells. Wild-type C57BL/6 inbred mice express the Ptprc^b (CD45.2 or Ly5.2) allele.

Detailed description

These triple mutant mice were generated by crossing Stock No. 024048 mice to Stock No. 002014 mice. Mice that are homozygous for all 3 alleles are viable and fertile. The Pkm, pyruvate kinase muscle, gene encodes different splicing variant isoenzymes which are involved in glycolysis. The pyruvate kinase M2 isoform is found in tumor cells, some normal tissues, and is the major pyruvate kinase in bone marrow hematopoietic cells. The Pkm^tm1.1Mgvh (Pkm2^fl) allele possesses loxP sites flanked exon 10. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exon 10 of the Pkm gene deleted in the cre-expressing tissues. Removal of the floxed Pkm sequence creates a null allele. These mice also carry the Ptprc^a pan leukocyte marker commonly known as CD45.1 or Ly5.1, which allows tracking of transplanted hematopoietic cells. Wild-type C57BL/6 inbred mice express the Ptprc^b (CD45.2 or Ly5.2) allele.

Development

These triple mutant mice were generated by crossing Stock No. 024048 mice to Stock No. 002014 mice. The mice are homozygous for all 3 alleles.

To generate the Pkm^tm1.1Mgvh allele, a targeting vector containing a FRT site flanked NEO cassette upstream of exon 9 of the targeted gene, and loxP sites flanking exon 10 was electroporated into 129S6/SvEvTac derived TC1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were crossed to mice (on an unconfirmed B6;129 genetic background) expressing FLP1 (FlpO) recombinase (ROSA26Flpo) to excise the NEO cassette. Mice that retained the loxP site flanked exon 10 were then bred to remove the FLP1 (FlpO) recombinase allele. Heterozygotes were crossed to generate homozygotes.

To generate the Pep Boy strain (Stock No. 002014), the Ptprc^a allele and closely linked Pepc^b allele were serially backcrossed from SJL/J onto C57BL/6 with selection at each generation for Ptprca by serotyping (Shen et al., 1985). In 1990 this strain, then housed at Sloan Kettering, was imported into The Jackson Laboratory from Edward Boyse at generation N22. Since its arrival, the strain has been maintained by sibling inbreeding. In 2005 it reached generation N22F55.

Allele

Symbol: Pepc^b
Name: b variant
MGI accession ID: MGI:4819861
Generation method: Not Applicable
Synonyms: Pep3^b
Marker symbol: Pepc
Marker name: peptidase C
Marker synonyms: Dip-1; Pep3; Pep-3
Chromosome: 1
Strain of origin: Not Applicable
Molecular note: The Pepc gene controls electrophoretic variation of peptidase C (PEP-C; EC 3.4.11.-) of red blood cells. The allele Pepc^b determines a faster migrating band and is found in the CBA/J and A/He strains.

Allele

Symbol: Pkm^tm1.1Mgvh
Name: targeted mutation 1.1, Matthew G Vander Heiden
MGI accession ID: MGI:5547750
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Modified isoform(s); No functional change
Synonyms: Pkm2^fl
Marker symbol: Pkm
Marker name: pyruvate kinase, muscle
Marker synonyms: CTHBP; HEL-S-30; OIP3; p58; PK; Pk-2; PK3; Pk-3; PKM12; Pkm2; TCB; THBP1
Chromosome: 9
Strain of origin: 129S6/SvEvTac
Molecular note: A targeting vector was designed to contain an FRT-flanked neomycin cassette upstream of exon 9, and loxP sites that flank exon 10 which is alternatively spliced only in the Pkm2 isoform. Mutant mice were bred with mice expressing FlpO recombinase (Gt(ROSA)26Sor) to remove the neomycin selection cassette. When these mutant mice are bred to mice that express Cre recombinase, the resulting offspring will have exon 10 deleted in the cre-expressing tissues: pyruvate kinase M2 isoform expression is eliminated, while pyruvate kinase M1 isoform expression is unchanged.

Allele

Symbol: Ptprc^a
Name: a variant
MGI accession ID: MGI:4819849
Generation method: Not Applicable
Synonyms: CD45.1; Ly5^a; Ptprc^SJL
Marker symbol: Ptprc
Marker name: protein tyrosine phosphatase, receptor type, C
Marker synonyms: B220; CD45; CD45R; GP180; IMD105; LCA; L-CA; LY5; Ly-5; Lyt-4; RT7; T200
Chromosome: 1
Strain of origin: Not Applicable
Site of expression: Widely expressed on all adaptive and innate immune cells.
Molecular note: Ptprc^a is found in strains SJL/J, STS/A, and DA. Ptprc^b is found in strains C57BL/6, C3H/An, DBA/2, AKR, and many others (J:13367, J:12054, J:12077, J:8603). Twelve nucleotide differences between the a and b alleles have been identified. These base substitutions correspond to five amino-acid changes within the extracellular domain of the encoded protein. These amino-acid differences are clustered in a region that also contains the greatest divergence between mouse and rat sequences (J:22485).

Note that the allele designations originally described were reversed in 1987 (J:8603); all publications prior to 1987 show SJL/J, STS/A, and DA as having the b allele and the C57BL/6J group as having the a allele (J:22341).