STOCK Nrp2^tm1.2Mom/MomJ

Stock number: 006700
Product name: NP2-Δ
Strain synonyms: Neuropilin-2-delta

Description

These neuropilin-2 knock-out reporter mice reveal improper axonal innervation of the main olfactory bulb and accessory olfactory bulb by olfactory sensory neurons and vomeronasal sensory neurons, respectively.

Detailed description

Neuropilin-2 mutant mice exhibit penetration of olfactory sensory neuronal axons into the deeper layers of the main olfactory bulb. In the vomeronasal system, axonal fasciculation within the vomeronasal nerve is affected; some axons are misrouted and innervate glomeruli in an ectopic domain of the accessory olfactory bulb.

Development

The Nrp2 targeted mutation was generated in 129P2/OlaHsd derived E14 ES cells and has a loxP-tauGFP-pA⁺-FNF cassette inserted into the first intron and a corresponding loxP site inserted upstream of the start codon. The FRT-flanked neomycin resistance sequence (FNF) was excised by crossing to mice with the Tg(ACTB-flp)4917Dym transgene insertion, which was generated in a mixed B6;SJL background, yielding the Nrp2 targeted mutation on a mixed background that is predominantly 129P2 and C57BL/6. The transgene was selectively bred out of the line. Exon 1 and the first part of intron 1 were excised by cre recombination by breeding to mice carrying Tg(EIIa-cre)C5379Lmgd, a transgene generated in FVB/N but having been backcrossed at least four generations to C57BL/6 before this cross and having unknown pedigree prior to that. The resulting offspring, bearing the Nrp2^tm1.2 mutation, were intercrossed and the transgene was selectively bred out of the line.

Allele

Symbol: Nrp2^tm1.2Mom
Name: targeted mutation 1.2, Peter Mombaerts
MGI accession ID: MGI:2183904
Generation method: Targeted
Attributes: Reporter; Null/Knockout
Marker symbol: Nrp2
Marker name: neuropilin 2
Chromosome: 1
Strain of origin: 129P2/OlaHsd
Expressed genes: GFP,Green Fluorescent Protein,
Site of expression: Axons of Nrp2-expressing neurons.
Molecular note: A loxP site 272 bp upstream of the translation initiation codon was introduced into exon 1 and a loxP-tauGFP FRT-flanked neo cassette was inserted 1 kb into intron 1 via homologous recombination. Heterozygous animals were crossed to an flp recombinase transgenic line for removal of the neo cassette. Subsequent mating to a cre recombinase transgenic line removed exon 1 and part of intron 1 leaving the tauGFP cassette intact. The exon 1 deletion removes the plasma membrane-targeting signal sequence and also brings the tauGFP cassette under the control of the endogenous promoter. RT-PCR analysis confirmed the removal of the signal sequence in gene transcripts from homozygous mutant animals. Immunohistochemistry of brain sections from homozygous mutants did not detect protein product.