B6.129-Clcn3^tm1Lamb/DnelJ

Stock number: 039307
Product name: ClC3 KO
Research areas: Cell Biology Research, Internal/Organ Research, Neurobiology Research

Description

ClC3 knock-out (KO) mice harbor a mutation generated by insertion of a neomycin cassette replacing part of exon 6 and exon 7 of the Clcn3 gene; this insertion results in disruption of the gene leading to significant reduction of ClC3 protein. These ClC3 KO mice may be useful for studying the role of ClC3 in ion transport and homeostasis, regulation of neuronal membrane excitability and bone formation.

Of note, the donating laboratory has also made a ClC5 knock-out (KO) mouse model available as Stock No. 039308.

Detailed description

Chloride channel protein 3, coded by Clcn3, is an intracellular membrane protein primarily involved in vesicular chloride transport for secretion in endosomes and synaptic vesicles. This protein has been identified as a key regulator of neuronal excitability, bone development, β-cell insulin processing and secretion as well as cardiac and smooth muscle cell contractility. These ClC3 knock-out (KO) mice were generated by replacing 13bp of exon 6 and all of exon 7 sequence with a neomycin cassette; this deleted region encoded a portion of the transmembrane domain 2 and all of transmembrane domains 3 and 4.

Heterozygous mice are viable and fertile with no overt phenotype. Homozygous mice are viable but demonstrate a reduced body size and impaired bone formation compared to wildtype littermates. Median survival for homozygous mice is ~6 months of age. Osteoblasts from ClC3 KO mice show ~40% reduction of ClC3 protein compared to wildtype controls. These mice may be useful for studying the function of ClC3 in ion transport and homeostasis.

Of note, the donating laboratory has also made a ClC5 knock-out (KO) mouse model available as Stock No. 039308.

Development

The ClC3 knock-out (KO) allele, created by Dr. Fred S. Lamb, was generated by replacing 13bp of exon 6 and all of exon 7 of the chloride channel, voltage-sensitive 3 (Clcn3) gene with a neomycin cassette by homologous recombination. The deleted region encoded a portion of transmembrane domain 2 and all of transmembrane domains 3 and 4. The targeting construct was electroporated into (129X1/SvJ x 129S1/Sv)F1-Kitl⁺-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts and the resulting chimeric mice were bred to C57BL/6J mice for germline transmission. Heterozygous mice, with neomycin cassette intact, were then bred to C57BL/6J mice for at least 10 generations by the donating laboratory (see SNP note below). 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 (Stock No. 000664) oocytes.

In 2024, 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 males sent to The Jackson Laboratory Repository. Two of the 43 markers throughout the genome were segregating with 129. Also, 2 of the 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/6N;C57BL/6J genetic background.

Allele

Symbol: Clcn3^tm1Lamb
Name: targeted mutation 1, Fred S Lamb
MGI accession ID: MGI:2447864
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: Clcn3^-
Marker symbol: Clcn3
Marker name: chloride channel, voltage-sensitive 3
Marker synonyms: Clc3; ClC-3; NEDHYBA; NEDSBA
Chromosome: 8
Strain of origin: (129X1/SvJ x 129S1/Sv)F1-Kitl⁺
Molecular note: Sequence encompassing a portion of exon 6 and all of exon 7 was replaced with a neomycin selection cassette inserted by homologous recombination. The deleted region encoded a portion of transmembrane domain 2 and all of transmembrane domains 3 and 4. Protein was undetected by Western blot analysis of brain tissue obtained from homozygous mutant mice.