B6(Cg)-Pam^tm1.1Npl/J

Stock number: 034076
Product name: PAM^cKO
Research areas: Research Tools

Description

PAM^cKO floxed mice possess loxP sites flanking exons 2-3 of the peptidylglycine alpha-amidating monooxygenase (Pam) gene. These floxed mice are useful when studying importance of peptidergic communication in specific tissues and at specific developmental times.

Detailed description

PAM^cKO floxed mice possess loxP sites flanking exons 2-3 of the peptidylglycine alpha-amidating monooxygenase (Pam) gene. PAM is a cuproenzyme involved in the posttranslational processing of peptide hormones including many neuropeptides. Complete knock-out mutations of PAM result in embryonic lethality. Mice that are homozygous for this floxed allele are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exons 2-3 deleted in the Cre-expressing tissues. This strain may be useful for studying the involvement of amidated neuropeptides in multiple systems including anxiety-spectrum disorders, copper deficiency, cardiovascular regulatory functions.

For example, when bred to Emx1-Cre mice (Stock No. 005628) expressing Cre recombinase in excitatory forebrain neurons, resulting offspring have less anxiety, increased locomotor responsiveness to cocaine, and improved thermoregulation in the cold.

In contrast, when bred to Myh6-cre mice (Stock No. 011038) expressing Cre recombinase in cardiomyocytes, resulting offspring have increased anxiety-like behavior and improved thermoregulation. They have decreased levels of atrial and serum levels of atrial natriuretic peptide (ANP), and changes are evident in gene expression in pathways related to cardiac function.

Development

The PAM^cKO targeting vector was designed to insert a loxP site upstream of exon 2 of the peptidylglycine alpha-amidating monooxygenase (Pam) gene. A rox-flanked neomycin selection (neo) cassette was inserted downstream of exon 3, followed by a second loxP site. The construct was electroporated into C57BL/6-derived embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts and resulting chimeric mice were bred to Dre recombinase expressing mice to remove the neo cassette. Offspring were crossed to remove the recombinase expressing transgene. PAM^cKO mice were bred to C57BL/6J mice (Stock No. 000664) for at least ten generations. 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.



In 2019 a 48 SNP (single nucleotide polymorphism) panel analysis, with 43 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the rederived living colony at The Jackson Laboratory Repository. While the 43 markers throughout the genome suggested a C57BL/6 genetic background, 4 of 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J ; C57BL/6N genetic background.

Allele

Symbol: Pam^tm1.1Npl
Name: targeted mutation 1.1, Neuropeptide Laboratory
MGI accession ID: MGI:6360953
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed)
Synonyms: PAM^cKO
Marker symbol: Pam
Marker name: peptidylglycine alpha-amidating monooxygenase
Marker synonyms: PAL; PAM-1; PHM
Chromosome: 1
Strain of origin: C57BL/6
Molecular note: The targeting vector is designed to insert a loxP site upstream of exon 2 and a rox-flanked neomycin selection (neo) cassette downstream of exon 3, followed by a second loxP site. Dre-mediated recombination removed the rox-flanked neo cassette leaving exons 2-3 floxed.