B6.129P2-Or10a4^tm1Mom/MomJ

Stock number: 007767
Strain synonyms: B6-P2-IRES-taulacZ
Research areas: Neurobiology Research, Research Tools, Sensorineural Research

Description

The P2-IRES-tau-lacZ knockin allele is designed to express tau-lacZ fusion protein from the olfactory receptor 17 (Olfr17) promoter/enhancer regions. These B6-P2-IRES-tau-lacZ mice may be useful to visualize the axonal projections from specific subpopulations of olfactory neurons.

Detailed description

The Or10a4^tm1Mom (formerly Olfr17^tm1Mom) knockin reporter allele has a an internal ribosome entry site and the microtubule-binding protein tau/beta-galactosidase (tau-lacZ) fusion protein downstream of the olfactory receptor family 10 subfamily A member 4 gene (Or10a4). Olfactory sensory neurons that express Or10a4 also co-express the tau-lacZ fusion protein by virtue of IRES-mediated co-translation. These neurons can be revealed by histochemistry of beta-galactosidase enzymatic activity, or by immunofluorescence with anti-beta-galactosidase antibodies. This reporter allele is combined with other olfactory receptor reporter alleles in Stock Number 027730.

In an attempt to offer alleles on well-characterized or multiple genetic backgrounds, alleles are frequently moved to a genetic background different from that on which an allele was first characterized. It should be noted that the phenotype of the Or10a4^tm1Mom mice could vary from that originally described for Or10a4^tm1Mom mice on a mixed B6;129P2 background. We may modify the strain description if necessary as published results become available.

Development

The P2-KO-13 targeting vector was designed to insert an internal ribosome entry site (IRES), a tau-lacZ fusion protein, and a loxP-flanked tk-neo cassette (LTNL) all downstream of the endogenous coding sequence. The construct was electroporated into 129P2/OlaHsd-derived E14 embryonic stem (ES) cells. The loxP-flanked neo cassette was then removed by transient transfection of a plasmid expressing cre recombinase, prior to injection of these ES cells into blastocysts. The resulting founder was bred to C57BL/6 and intercrossed. Subsequently, this allele was backcrossed more than ten generations to C57BL/6J prior to donation to The Jackson Laboratory Repository.

Allele

Symbol: Or10a4^tm1Mom
Name: targeted mutation 1, Peter Mombaerts
MGI accession ID: MGI:2179510
Generation method: Targeted
Attributes: Reporter
Marker symbol: Or10a4
Marker name: olfactory receptor family 10 subfamily A member 4
Chromosome: 7
Strain of origin: 129P2/OlaHsd
Expressed genes: lacZ,beta-galactosidase,E. coli
Site of expression: lacZ is expressed in olfactory sensory neurons.
Molecular note: Insertion of an IRES-tau-lacZ-loxP-tk-neo-loxP expression cassette placed the inserted sequences under control of the endogenous regulatory sequences. Transient expression of Cre recombinase in C57BL/6 blastocysts excised the thymidine kinase and neomycin sequences. This allele expresses a bicistronic mRNA encoding the receptor and a bovine tau-beta-galactosidase fusion protein.