These Klk4-null/lacZ knock-in (Klk4- or Klk4lacZ) mice harbor a nuclear-localized β-galactosidase "knock-in" mutation that also abolishes endogenous Klk4 (kallikrein related-peptidase 4 [prostase, enamel matrix, prostate]) gene function. These mice may be useful for studying the molecular mechanisms of enamel protein cleavage necessary for proper dental enamel formation/biomineralization/crystallization during tooth development.
Jan CC Hu, University of Michigan
Genetic Background | Generation |
---|---|
|
Allele Type | Gene Symbol | Gene Name |
---|---|---|
Targeted (Reporter, Null/Knockout) | Klk4 | kallikrein related-peptidase 4 (prostase, enamel matrix, prostate) |
Mice homozygous for the Klk4-null/lacZ knock-in allele (Klk4- or Klk4lacZ) are viable and fertile, with a nuclear-localized β-galactosidase (NLS lacZ) translation initiation site and coding region replacing the Klk4 translation initiation site and coding region. This abolishes endogenous gene function. Under control of the upstream promoter/enhancer elements, lacZ expression is directed to ameloblasts (the enamel-forming cells in developing teeth) during the transition and maturation stages of dental enamel formation. Klk4-deficiency results in improper dental enamel matrix biomineralization, altered gross tooth morphology, and premature tooth decay. Homozygous mice exhibit malformed enamel that is rapidly abraded after weaning (even when fed moistened chow) and a tendency for all teeth to fracture at points of contact. Heterozygous mice appear indistinguishable from wildtype mice. These Klk4lacZ mice may be useful for studying the molecular mechanisms of enamel protein cleavage necessary for proper dental enamel formation/biomineralization/crystallization during tooth development.
NLS lacZ activity may be readily distinguished from native mouse lacZ activity by its nuclear localization and high pH optima: mouse β-galactosidase is a lysosomal enzyme that is only marginally active at pH 7.5, whereas bacterial β-galactosidase can be strongly detected above pH 8 (Weiss et al, 1999 Histochem J 31:231).
A targeting vector was designed to insert a nuclear-localized β-galactosidase (NLS lacZ) gene and loxP-flanked PGK-Neo cassette into the first coding exon (exon 2), and also delete the entire coding region (exons 2-6), of the kallikrein 4 gene. This replaces the Klk4 translation initiation site and coding region with the NLS lacZ translation initiation site and coding region. The construct was electroporated into C57BL/6-derived Bruce4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts and male chimeras were mated to C57BL/6J females. Next, mutant mice were bred to "B6 Cre deleter" mice (coisogneic on C57BL/6) to remove the floxed neo cassette. The resulting mice harboring the Klk4-null/lacZ knock-in allele (Klk4- or Klk4lacZ) were selectively bred to remove the Cre transgene and then backcrossed to C57BL/6J mice for at least six generations prior to arrival at The Jackson Laboratory. Upon arrival, mutant mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.
Expressed Gene | lacZ, beta-galactosidase, E. coli |
---|---|
Site of Expression | lacZ expression is directed to ameloblasts (the enamel-forming cells in developing teeth) during the transition and maturation stages of dental enamel formation. |
Allele Name | targeted mutation 1.1, James P Simmer |
---|---|
Allele Type | Targeted (Reporter, Null/Knockout) |
Allele Synonym(s) | Klk4lacZ |
Gene Symbol and Name | Klk4, kallikrein related-peptidase 4 (prostase, enamel matrix, prostate) |
Gene Synonym(s) | |
Expressed Gene | lacZ, beta-galactosidase, E. coli |
Site of Expression | lacZ expression is directed to ameloblasts (the enamel-forming cells in developing teeth) during the transition and maturation stages of dental enamel formation. |
Strain of Origin | B6.Cg-Thy1a |
Chromosome | 7 |
Molecular Note | The genomic sequence spanning the initiation codon in exon 2 through exon 6 was replaced with an NLS-lacZ and floxed neo cassette. The neo cassette was subsequently removed by germ line, cre mediated recombination. This allele lacks the entire coding region. |
Mutations Made By | Jan CC Hu, University of Michigan |
When maintaining a live colony, heterozygous mice may be bred together, to wildtype siblings, or to C57BL/6J inbred mice (Stock No. 000664). Homozygous mice have "soft teeth" and benefit from being fed moistened chow.
When using the C57BL/6-Klk4tm1.1Jpsi/J mouse strain in a publication, please cite the originating article(s) and include JAX stock #010684 in your Materials and Methods section.
Facility Barrier Level Descriptions
Service/Product | Description | Price |
---|---|---|
Heterozygous for Klk4<tm1.1Jpsi> |
Frozen Mouse Embryo | C57BL/6-Klk4<tm1.1Jpsi>/J | $2595.00 |
Frozen Mouse Embryo | C57BL/6-Klk4<tm1.1Jpsi>/J | $2595.00 |
Frozen Mouse Embryo | C57BL/6-Klk4<tm1.1Jpsi>/J | $3373.50 |
Frozen Mouse Embryo | C57BL/6-Klk4<tm1.1Jpsi>/J | $3373.50 |
Terms are granted by individual review and stated on the customer invoice(s) and account statement. These transactions are payable in U.S. currency within the granted terms. Payment for services, products, shipping containers, and shipping costs that are rendered are expected within the payment terms indicated on the invoice or stated by contract. Invoices and account balances in arrears of stated terms may result in The Jackson Laboratory pursuing collection activities including but not limited to outside agencies and court filings.
The Jackson Laboratory has rigorous genetic quality control and mutant gene genotyping programs to ensure the genetic background of JAX® Mice strains as well as the genotypes of strains with identified molecular mutations. JAX® Mice strains are only made available to researchers after meeting our standards. However, the phenotype of each strain may not be fully characterized and/or captured in the strain data sheets. Therefore, we cannot guarantee a strain's phenotype will meet all expectations. To ensure that JAX® Mice will meet the needs of individual research projects or when requesting a strain that is new to your research, we suggest ordering and performing tests on a small number of mice to determine suitability for your particular project. We do not guarantee breeding performance and therefore suggest that investigators order more than one breeding pair to avoid delays in their research.
What information were you hoping to find through your search?
How easy was it to find what you were looking for?
We may wish to follow up with you. Enter your email if you are happy for us to connect and reachout to you with more questions.
Please Enter a Valid Email Address
Thank you for sharing your feedback! We are working on improving the JAX Mice search. Come back soon for exciting changes.