STOCK Tg(tetO-ABL1*P242E*P249E)CPdav/J

Stock number: 014544
Research areas: Cell Biology Research, Immunology, Inflammation and Autoimmunity Research, Neurobiology Research, Research Tools

Description

This transgenic mouse has a Tet response element upstream of a human c-Abl 1b isoform modified to harbor two amino acid substitutions (P242E/P249E) in the conserved proline residues of the SH2-SH3 linker region that render the protein constitutively active (AblPP). Expression may be contoled via the Tet-Off/Tet-On system for use in studies related to tau phosphorylation.

Detailed description

Hemizygous AblPP transgenic mice are viable and fertile with no reported phenotypic abnormalities. The TRE-AblPP transgene has the Tet response element (TRE or tetO) upstream of a human c-Abl 1b isoform modified to harbor two amino acid substitutions (P242E/P249E) in the conserved proline residues of the SH2-SH3 linker region that render the protein constitutively active (AblPP). When bred with other mice expressing tetracycline-controlled transactivator protein (tTA) or reverse tetracycline-controlled transactivator protein (rtTA), AblPP expression in the resulting double mutant offspring can be regulated with tetracycline or its analog doxycycline (dox). As designed, AblPP transgenic mice have no reported levels of AblPP expression in the absence of tTA.

These AblPP transgenic mice allow Tet-Off/Tet-On expression of a constitutively active form of c-Abl, and may be may be useful for studying tau phosphorylation and the pathogenesis of neurodegeneration/neuroinflammation associated with Alzheimer's disease. For example, when bred to a strain expressing tTA in forebrain neurons (Stock No. 007004), the resulting AblPP/tTA double mutant mice develop early reactive gliosis and astrocyctosis that continues to a severe, progressive neurodegeneration in the CA1 region of the hippocampus. Such double mutant mice will be available as Stock No. 015838.

Development

The TRE-AblPP transgene was designed with a Tet response element (TRE) followed by a constitutively active c-Abl sequence (AblPP) and a beta-globin polyA sequence. The Tet response element (TRE) contains seven copies of the 42-bp tet operator sequence (tetO) just upstream of a minimal CMV promoter. To generate the AblPP sequence, a cDNA sequence encoding the nuclear-localizing isoform (1b) of the human c-Abl (ABL1; c-abl oncogene 1, non-receptor tyrosine kinase) was modified via site-directed mutagenesis to change the conserved proline residues of the SH2-SH3 linker region to glutamate (P242E/P249E). The 5.4 kb TRE-AblPP transgene was injected into the embryos of FVB/NTac mice. Founder mice were bred with FVB/NTac mice to establish founder line C. The colony was then maintained for several generations by breeding TRE-AblPP females with CaMKIIa-tTA males (on a C57BL/6 genetic background; see Stock No. 007004). During this time, two generations of backcrossing TRE-AblPP males with C57BL/6J females are also reported. TRE-AblPP transgenic mice (not harboring the Camk2a-tTA transgene) on a mixed C57BL/6J;FVB/N genetic background were sent to The Jackson Laboratory Repository (see SNP note below). Upon arrival, TRE-AblPP transgenic mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.

A 27 SNP (single nucleotide polymorphism) panel analysis covering all 19 chromosomes and the X chromosome was performed on the rederived living colony at The Jackson Laboratory Repository. 13 of 27 markers (representing 12 different chromosomes) were found to be segregating for allele-type other than C57BL/6. Ten of these 13 markers had the allele-type shared by FVB/NJ and CBA/J. The other three markers (one each on chromosomes 5, 11, and 16) were neither C57BL/6J nor FVB/NJ allele-type, and had the allele-type shared by CBA/J. Taken with the strain development history, these data suggest the mice sent to The Jackson Laboratory Repository are a mix of C57BL/6 and FVB/N, with some remaining CBA genomic contributions left over from the CaMKIIa-tTA breedings.

Allele

Symbol: Tg(tetO-ABL1*P242E*P249E)CPdav
Name: transgene insertion C, Peter Davies
MGI accession ID: MGI:4940842
Generation method: Transgenic
Attributes: Inducible; Constitutively active; Inserted expressed sequence; Humanized sequence
Marker symbol: Tg(tetO-ABL1*P242E*P249E)CPdav
Marker name: transgene insertion C, Peter Davies
Chromosome: UN
Strain of origin: FVB/NTac
Expressed genes: ABL1,ABL proto-oncogene 1, non-receptor tyrosine kinase,human
Site of expression: In the absence of dox (off-dox), AblPP/tTA mice exhibit forebrain-specific neuronal expression of the constitutively active AblPP. No significant AblPP expression is observed in the cerebellum or brainstem (with or without dox). Greatly increased c-Abl kinase activity (20- to 30-fold) and increased c-Abl phosphorylation at tyrosine 412 is observed in the forebrain of AblPP/tTA mice off-dox compared to control mice. AblPP/tTA mice exhibit substantial microgliosis (beginning ~3 weeks off-dox) and astrocyctosis (beginning ~6-9 weeks off-dox).
Molecular note: The TRE-AblPP transgene was designed with a Tet response element (TRE) followed by a constitutively active c-Abl sequence (AblPP) and a beta-globin polyA sequence. The Tet response element (TRE) contains seven copies of the 42-bp tet operator sequence (tetO) just upstream of a minimal CMV promoter. To generate the AblPP sequence, a cDNA sequence encoding the nuclear-localizing isoform (1b) of the human c-Abl (ABL1; c-abl oncogene 1, non-receptor tyrosine kinase) was modified via site-directed mutagenesis to change the conserved proline residues of the SH2-SH3 linker region to glutamate (P242E/P249E).