STOCK Vip^tm1(cre)Zjh/J

Stock number: 010908
Product name: Vip-IRES-cre
Research areas: Neurobiology Research, Research Tools

Description

Vip-IRES-Cre mice have Cre recombinase expression directed to Vip-expressing cells by the endogenous promoter/enhancer elements of the vasoactive intestinal polypeptide locus. Cre activity is detected in the neocortex, hippocampus, olfactory bulb, suprachiasmatic nuclei, and other discrete midbrain and brainstem regions. These mice may be useful to study neural GABAergic circuits throughout the mammalian brain.

While Vip-IRES-Cre was designed to retain endogenous Vip expression, a 2019 publication indicates this allele has reduced Vip expression - see details below. As such, researchers may use homozygous mice for routine colony maintenance, but should consider using heterozygous Vip-IRES-Cre mice and wildtype littermate controls in all their studies.

Of note, the same Vip-IRES-Cre allele is also available on a C57BL/6J genetic background as Stock No. 031628.

Detailed description

The Vip-IRES-Cre allele harbors an internal ribosome entry site and Cre recombinase in the 3' UTR of the vasoactive intestinal polypeptide locus (Vip). As such, it is designed to have the endogenous Vip promoter/enhancer elements directing cre expression in the neocortex, hippocampus, olfactory bulb, suprachiasmatic nuclei and other discrete midbrain and brainstem regions. When Vip-IRES-Cre mice are bred with mice containing loxP-flanked sequences, Cre-mediated recombination will result in deletion of the floxed sequences in the Vip-expressing cells in the offspring. While Vip-IRES-cre was designed to retain endogenous Vip expression, a 2019 publication indicates this allele has reduced Vip expression - see details below. As such, researchers may use homozygous mice for breeding, but should consider using heterozygous Vip-IRES-Cre mice and wildtype littermate controls in all their studies.

In 2010, the donating investigator reported Cre recombinase activity is specific and efficient (largely recapitulates the endogenous Vip expression pattern with highly efficient recombination). They report Cre recombinase activity in some GABAergic interneurons, and did not examine cre expression in the intestine or tissues other than brain. VIP expression from this Vip-IRES-Cre allele was not evaluated by the donating investigator (January 2010) - see additional details below. They also reported that homozygous mice are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities.

For characterization information, see images at the Allen Institute for Brain Science website (Vip-IRES-Cre images).

If the recombinase activity pattern of this allele is further characterized by the Genetic Resource Science group at The Jackson Laboratory, such findings will be reported on the Mouse Genome Informatics (MGI) Allele Detail entry (Vip^tm1(cre)Zjh). This same information would also be found searching the MGI Recombinase Activity database.

While this Vip-IRES-cre allele was designed as a 3' knock-in allele, Cheng et al. 2019 J Biol Rhythms (PMID:31452438) indicates the Vip-IRES-cre allele has reduced Vip expression. When examined at 2 days of age, Vip-IRES-cre heterozygotes exhibit reduced expression of the neuropeptide products encoded by the Vip gene (VIP and peptide histidine isoleucine [PHI]) in the suprachiasmatic nucleus (SCN) of the hypothalamic nucleus, when compared to wildtype littermates. The total number of VIP/PHI-positive neurons within the SCN was not different between Vip-IRES-cre heterozygotes and wildtype littermates - ruling out a potential loss of VIP/PHI neurons. Expression of other neuropeptides was not altered. The wheel-running activity rhythms of heterozygous mice were not affected.

Development

The Vip-IRES-Cre knock-in allele was designed by Dr. Z. Josh Huang (Cold Spring Harbor Laboratory). A targeting vector was designed to insert an internal ribosome entry site (IRES), a Cre recombinase sequence, an SV40 polyA signal and a frt-flanked neo cassette into the 3' untranslated region (after the translational termination site) of the vasoactive intestinal polypeptide locus (Vip) on chromosome 10. This construct was electroporated into (C57BL/6 x 129S4Sv/Jae)-derived V6.5 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient tetraploid blastocysts. Chimeric animals were bred with Actin-FLPe mice (on a C57BL/6-congenic background [N10]; see Stock No. 005703) to generate the colony and remove the neo selection cassette. The resulting Vip-IRES-Cre mice were subsequently bred together for several generations (and the FLPe transgene was removed). In 2010, Vip-IRES-Cre knock-in mice on a mixed genetic background (C57BL/6;129S4 ; animals showing either agouti or black coat color) were sent to The Jackson Laboratory Repository. Upon arrival, sperm was cryopreserved. An aliquot of that frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664) and rederive our live colony as Stock No. 010908 - which was thereafter maintained by breeding mutant mice together.

Allele

Symbol: Vip^tm1(cre)Zjh
Name: targeted mutation 1, Z Josh Huang
MGI accession ID: MGI:4431361
Generation method: Targeted
Attributes: Recombinase-expressing
Marker symbol: Vip
Marker name: vasoactive intestinal polypeptide
Chromosome: 10
Strain of origin: (C57BL/6 x 129S4/SvJae)F1
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: Cre recombinase activity is observed in some GABAergic interneurons.
Molecular note: A targeting vector was designed to insert an internal ribosome entry site (IRES), a cre recombinase sequence, an SV40 polyA signal, and an frt-flanked neo cassette into the 3' untranslated region (after the translational termination site) of the vasoactive intestinal polypeptide locus (Vip). This construct was electroporated into C57BL/6 x 129S4/SvJae hybrid embryonic stem (ES) cells. Chimeric mice were bred with Actin-FLPe mice (on a C57BL/6 congenic background) to generate the colony and remove the neo selection cassette. The FLPe transgene has been bred out of the line.