B6(Cg)-Psen2^{tm2.1(PSEN2*N141I)Mdk} Isr(HSA19;APOE_i4)2Mdk Isr(HSA17;MAPT*N279K)4Mdk Psen1^{tm4.1(PSEN1*V272A)Mdk} App^{tm1.1(APP)Mdk}/J

Stock number: 040827
Product name: PSEN2-GR*N141I(5X-GR)
Strain synonyms: PSEN2-GR*N141I; APOE-GR*ε4; MAPT-GR*N279K; PSEN1-GR*V272A; APP-GR wt;
Research areas: Mouse/Human Gene Homologs, Neurobiology Research

Description

This strain was created by combining the following alleles: Psen2^{tm2.1(PSEN2*N141I)Mdk}, B6J.B6N-Isr(HSA19;APOE_i4)2Mdk/J (Stock No. 038919), B6J.B6N(Cg)-Isr(HSA17;MAPT*N279K)4Mdk/J [MAPT(H1.0*)N279K-GR] (Stock No. 035794), Psen1^{tm4.1(PSEN1*V272A)Mdk} (PSEN1-GR*V272A), App^{tm1.1(APP)Mdk} (APP-GR wt) (Stock No. 038920).

The combination creates a humanized knock-in/knock-out that has human genes replacing mouse genes at the Psen2 with human PSEN2 having amino acid substitution mutation N141I , the mouse genomic region from Apoe (apoliprotein E) to Apoc (apoliprotein C) is exchanged for the 47 kb human genomic region APOE to APOC which includes human APOEε4, a syntenic 190 kb region from human chromosome 17 (HSA17) that includes SPPLC2 (signal peptide peptidase 2C) and MAPT (microtubule-associated protein tau), specifically the H1 haplotype with the pathogenic N279K mutation, Psen1 with human PSEN1 having amino acid substitution mutation V272A and human APP replacing the mouse App locus. This strain may serve as model with alterations in PSEN1 to explore more fully the role of the PSEN1, APP and MAPT in Alzheimer's disease (AD).

Detailed description

This strain was created by combining the following alleles: Psen2^{tm2.1(PSEN2*N141I)Mdk} (PSEN2-GR*N141I), B6J.B6N-Isr(HSA19;APOE_i4)2Mdk/J (Stock No. 038919), B6J.B6N(Cg)-Isr(HSA17;MAPT*N279K)4Mdk/J [MAPT(H1.0*)N279K-GR] (Stock No. 035794), Psen1^{tm4.1(PSEN1*V272A)Mdk} (PSEN1-GR*V272A), App^{tm1.1(APP)Mdk} (APP-GR wt) (Stock No. 038920).

Presenilin 2 is a subunit of the gamma-secretase complex which cleaves beta-amyloid precursor protein and NOTCH receptor proteins. These humanized Psen2 knock-in/knock-out mice carry a 113 kb fragment of human PSEN2 having amino acid substitution mutation N141I replacing the mouse Psen2 locus. PSEN2 N141I is a rare genetic mutation in the Presenilin 2 (PSEN2) gene, linked to a highly penetrant, early-onset form of familial Alzheimer's disease (fAD), an inherited form of AD that typically develops before the age of 65. PSEN2 mutations can cause an imbalance in the processing of Aβ, resulting in the accumulation of Aβ plaques in the brain.

The humanized interspecies replacement (Isr) APOE4-GR (gene replacement) mice are a knock-in/knock-out model in which the mouse genomic region (Chr7:19,404,448-19,434,653; 3,0206bp) between but not including Tomm40 (translocase of outer mitochondrial membrane 40) to Clptm1 (cleft lip and palate associated transmembrane protein 1) are replaced by the human syntenic region containing APOE to APOC (including promoter, regulatory and intergenic regions, Chr19:44,904,076-44,951,132; 47,057bp), which includes the APOEε4 locus. The Apoc/APOC region includes Apoc1, Apoc4, Apoc2. APOEε4 differs from APOEε3 by an arginine (CGC) rather than cysteine (TGC) at SNP rs429358 (Ensembl, SNPedia). The APOE Ε4 (ApoE4) allele is the strongest genetic risk factor for developing late-onset Alzheimer's disease and also increases the risk of dementia with Lewy bodies. Homozygous mice are viable and fertile with no obvious anatomical or behavioral issues.

The interspecies replacement (Isr) MAPT(H1.0*)N279K-GR (Gene Replacement) mice contain a syntenic 190 kb region from human chromosome 17 (HSA17) that includes SPPLC2 (signal peptide peptidase 2C) and MAPT (microtubule-associated protein tau), specifically the H1 MAPT haplotype modified to express the N279K mutation. The region replaces ~157 kb on mouse chromosome 11 stretching from, but not including, Crhr1 to Kansl1. The SPPL2C sequence is included because it is embedded entirely in the MAPT-AS1 transcribed region. Human MAPT (microtubule-associated protein tau) is found within a 900 kb inversion on Chr 17q21 that defines two haplotypes, H1 and H2, found in Caucasians. The haplotypes are distinguished by a series of polymorphisms that include the MAPT sequence. A227A (GCA to GCG), is a silent point mutation in exon 9 of the MAPT isoform 441. The minor G allele is carried by H2 and the A allele is found in the more common H1 haplotype. H1 is linked with late onset Alzheimer's disease (AD) risk, progressive supranuclear palsy, Parkinson's disease, and corticobasal degeneration. H2 is associated with decreased risk of late onset AD, and lower MAPT levels in the cerebellum and temporal cortex. Homozygous mice are viable and fertile and exhibit no obvious phenotype. These mice express the human MAPT (H2 haplotype), MAPT-AS1 transcripts and the typical MAPT protein isoforms.

Presenilin 1 is the catalytic subunit of the gamma-secretase complex which cleaves beta-amyloid precursor protein and NOTCH receptor proteins. These humanized Psen1 knock-in/knock-out mice carry a 106 kb fragment of human PSEN1 having amino acid substitution mutation V272A replacing the mouse Psen1 locus.

Amyloid beta (A4) precursor protein (APP) is a type I integral membrane protein that is cleaved to form a number of peptides, in particular, the amyloid-β-peptide, a component of the amyloid plaques associated with Alzheimer's disease. These humanized App knock-in/knock-out mice carry a 350 kb fragment of human APP replacing the mouse App locus.

The strain also has a humanized ApoE knock-in mutation (sequence coding for isoform E4), and the human MAPT (H2.1 haplotype), MAPT-AS1 transcripts and the typical MAPT protein isoforms, including SPPL2C. Additional information on each allele may be obtained from the respective stock number entry.

Mice homozygous for all five alleles are viable and fertile.

Development

This strain was created by combining the following alleles: Psen2^{tm2.1(PSEN2*N141I)Mdk}, B6J.B6N-Isr(HSA19;APOE_i4)2Mdk/J (Stock No. 038919), B6J.B6N(Cg)-Isr(HSA17;MAPT*N279K)4Mdk/J [MAPT(H1.0*)N279K-GR] (Stock No. 035794), Psen1^{tm4.1(PSEN1*V272A)Mdk} (PSEN1-GR*V272A), App^{tm1.1(APP)Mdk} (APP-GR wt) (Stock No. 038920).

The PSEN2-GR targeting vector is designed to insert a 113 kb (Chr1:226,823,270-226,935,953) fragment of the human PSEN2 (presenilin 2) having amino acid substitution mutation N141I [rs63750215 A>T; AAC (N) to ATC (I)] in place of Chr1:180,028,072-180,100,006 of the mouse Psen2 gene on chromosome 1. The construct included loxP-flanked neomycin selection cassette. The insertion disrupts PSen2 transcription. The construct was electroporated into C57BL/6N-PRX-B6N embryonic stem cells (ES). The neomycin cassette was removed by transient expression of Cre. Correctly targeted ES cells were injected into blastocysts. Chimeric animals were backcrossed to C57BL/6J mice for at least 5 generations.

A 30 kb deletion on mouse chromosome 7 stretching from Apoe to Apoc is replaced by a syntenic 47 kb region from human chromosome 19 (HSA19). In this transchromosomal (Tc) strain, the mouse Apoe (apoliprotein e) isoform 4 and Apoc (apolipoprotein C) genes are replaced by human APOE (isoform E4) and APOC genes. A neomycin resistance cassette was included in the construct. The deletion/insertion was made using C57BL/6N-PRX-B6N embryonic stem cells (ES) and loxP-flanked neomycin resistance cassette was removed by transient expression of cre. Correctly targeted ES cells were injected into blastocysts. Mice were backcrossed to C57BL/6J mice (Stock No. 000664) for at least 5 generations by the donating laboratory. 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.

The MAPT-GR(H1.0*N279K) targeting event is designed to insert a syntenic 190.5 kb region from human chromosome 17 (HSA17; Chr17:45,838,648-46,029,144) in place of a 156.5 kb of mouse chromosome 11 (Chr11:104,066,949-104,223,491) stretching from, but not including, Crhr1 to Kansl1. The genomic sequences are from mouse assembly GRCm39 and human assembly GRCh38.p14 [PMID:38343132 Benzow et al., 2024 Alzheimers Dement. 20:3080]. In this interspecies replacement (Isr) strain, the mouse Sppl2c (signal peptide peptidase 2C) and Mapt (microtubule-associated protein tau) genes are replaced by human SPPL2C and MAPT (H1 haplotype) genes. The human MAPT gene was modified to include the N279K (asparaginine to lysine) mutation identified in FTD patients. The deletion/insertion was made using C57BL/6N-PRX-B6N embryonic stem cells (ES) and a loxN-flanked neomycin resistance cassette that was removed by transient cre expression prior to establishing the mouse line. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were crossed to C57BL/6J females. At some point MAPT(H1.0*)N279K-GR mice were crossed to mice carrying Tyr^c-2J, which was later bred out.

The PSEN1-GR*V272A targeting vector is designed to insert a 106 kb (Chr14:73,121,400-73,227,703) fragment of the human PSEN1 (presenilin 1) having amino acid substitution mutation V272A in place of Chr12:83,730,110-83,793,335 of the mouse Psen1 gene on chromosome 12. The construct included loxP-flanked neomycin selection cassette. In addition, there is also a PSEN1-DT (non-coding antisense RNA) in the human genome segment. The insertion disrupts PSen1 transcription. The construct was electroporated into C57BL/6N-PRX-B6N embryonic stem cells (ES). The neomycin cassette was removed by transient expression of Cre. Correctly targeted ES cells were injected into blastocysts. Chimeric animals were backcrossed to C57BL/6J mice for at least 5 generations.

The APP-GR wt targeting vector is designed to insert a 343 kb (Chr21:25,880,264-26,224,036) fragment of the human APP (apolipoprotein) in place of 268 kb (Chr16:84,750,107-85,019,011) of the mouse App gene on chromosome 16. The construct included a loxP-flanked neomycin selection cassette. In addition, there is also a APP-DT (non-coding antisense RNA) in the human genome segment. The insertion disrupts App transcription. The construct was electroporated into C57BL/6N-PRX-B6N embryonic stem cells (ES). The neomycin cassette was removed by transient expression of Cre. Correctly targeted ES cells were injected into blastocysts. Chimeric animals were backcrossed to C57BL/6J mice for at least 5 generations.

Upon arrival at The Jackson Laboratory Repository, the strain was cryopreserved as embryos.

The genomic sequences are from human assembly GRCh38.p14 and the mouse assembly GRCm39.

Allele

Symbol: Psen2^{tm2.1(PSEN2*N141I)Mdk}
Name: targeted mutation 2.1, Michael D Koob
MGI accession ID: MGI:8318853
Generation method: Targeted
Attributes: Null/Knockout; Inserted expressed sequence; Humanized sequence
Synonyms: PSEN2-GR*N141I
Marker symbol: Psen2
Marker name: presenilin 2
Marker synonyms: AD3L; AD4; Ad4h; ALG-3; CMD1V; PS2; PS-2; STM2
Chromosome: 1
Strain of origin: C57BL/6NTac

Allele

Symbol: App^{tm1.1(APP)Mdk}
Name: targeted mutation 1.1, Michael D Koob
MGI accession ID: MGI:7565473
Generation method: Targeted
Attributes: Inserted expressed sequence; Humanized sequence
Synonyms: APP-GR
Marker symbol: App
Marker name: amyloid beta (A4) precursor protein
Marker synonyms: AAA; Abeta; ABPP; AD1; Adap; alpha-sAPP; APPI; appican; betaAPP; CTFgamma; Cvap; E030013M08Rik; PN2; PN-II; preA4; protease nexin II
Chromosome: 16
Strain of origin: C57BL/6NTac
Molecular note: The targeting vector is designed to insert a 343 kb (Chr21:25880264 - 26224036) fragment of the human APP (apolipoprotein) in place of 268 kb (Chr16:84750107 - 85019011) of the mouse App gene. The construct includes an FRT-flanked neomycin selection cassette. In addition, there is also a APP-DT (non-coding antisense RNA) in the human genome segment. The insertion disrupts App transcription.The neomycin cassette was removed by transient expression of cre.

Allele

Symbol: Psen1^{tm4.1(PSEN1*V272A)Mdk}
Name: targeted mutation 4.1, Michael D Koob
MGI accession ID: MGI:8246749
Generation method: Targeted
Attributes: Null/Knockout; Inserted expressed sequence; Humanized sequence
Synonyms: PSEN1-GR*V272A
Marker symbol: Psen1
Marker name: presenilin 1
Marker synonyms: ACNINV3; AD3; Ad3h; CMD1U; FAD; presenilin-1; PS1; PS-1; PSNL1; S182
Chromosome: 12
Strain of origin: C57BL/6NTac
Molecular note: The targeting vector is designed to insert a 106 kb (Chr14:73121400 - 73227703) fragment of the human PSEN1 having an amino acid substitution mutation V272A in place of Chr12:83730110 - 83793335 of the mouse Psen1 gene. The construct includes a loxP-flanked neomycin selection cassette. In addition, there is also a PSEN1-DT (non-coding antisense RNA) in the human genome segment. The insertion disrupts Psen1 transcription. The neomycin cassette was removed by transient expression of Cre.

Allele

Symbol: Isr(HSA17;MAPT*N279K)4Mdk
Name: interspecies replacement, human Chr 17, Michael Koob 4
MGI accession ID: MGI:6705043
Generation method: Targeted
Attributes: Inserted expressed sequence; Humanized sequence
Synonyms: MAPT(H1.0*N279K)-GR; Tc(HSA17*N279K)1Mdk
Marker symbol: Isr(HSA17;MAPT*N279K)4Mdk
Marker name: interspecies replacement, human Chr 17, Michael Koob 4
Marker synonyms: Tc(HSA17*N279K)1Mdk
Chromosome: 11
Strain of origin: C57BL/6NTac
Molecular note: A 157 kb deletion on mouse chromosome 11 stretching from, but not including, Crhr1 to Kansl1 is replaced by a syntenic 190 kb region from human chromosome 17 (HSA17). The mouse Sppl2c (signal peptide peptidase 2C) and Mapt (microtubule-associated protein tau) genes are replaced by human SPPL2C and MAPT (H1 haplotype) genes. The human MAPT gene was modified to include the N279K (asparaginine to lysine) mutation identified in FTD patients. A loxN-flanked neomycin resistance cassette that was removed by transient cre expression.

Allele

Symbol: Isr(HSA19;APOE_i4)2Mdk
Name: interspecies replacement, human Chr 19, Michael Koob 2
MGI accession ID: MGI:7565468
Generation method: Targeted
Attributes: Inserted expressed sequence; Humanized sequence
Synonyms: APOE4-GR; Tc(HSA19*APOE_i4)1Mdk
Marker symbol: Isr(HSA19;APOE_i4)2Mdk
Marker name: interspecies replacement, human Chr 19, Michael Koob 2
Marker synonyms: Tc(HSA19*APOE_i4)1Mdk
Chromosome: 7
Strain of origin: C57BL/6NTac
Molecular note: A 30 kb deletion on mouse chromosome 7 stretching from Apoe to Apoc is replaced by a syntenic 47 kb region from human chromosome 19 (HSA19). The mouse Apoe (apoliprotein e) isoform four and Apoc (apolipoprotein C) genes are replaced by human APOE (isoform E4) and APOC genes. A loxP-flanked neomycin resistance cassette is included in the construct. The neomycin cassette was removed by transient expression of Cre.