STOCK Nphs1^tm1Rkl/J

Stock number: 005692
Product name: Nephrin KO/GFP knock-in mice
Research areas: Developmental Biology Research, Internal/Organ Research, Research Tools

Description

These Nephrin KO/GFP knock-in mice may be useful in studying nephrotic syndrome or any of the diseases where plasma ultrafiltration is affected.

Detailed description

Mice that are heterozygous for the Nephrin KO/GFP knock-in mutation are viable and fertile. Homozygous mice die within a few days after birth with massive glomerular vascular leak and an absence of glomerular epithelial slit diaphragms. No gene product is detected by Western blot of kidney tissue of homozygotes. Green fluorescent protein (GFP) is detected in glomeruli of homozygotes and heterozygotes. Newborn homozygotes show extensive proteinuria, while heterozygotes show none. These Nephrin KO/GFP knock-in mice may be useful in studying nephrotic syndrome or any of the diseases where plasma ultrafiltration is affected.

Development

A targeting vector was generated in which base pairs -1 to 33 surrounding the ATG start codon of exon 1 of the endogenous gene were replaced with an in-frame green fluorescent protein-polyadenylation stop followed by a phosphoglycerol kinase promoter-neomycin resistance-polyadenylation stop. The construct was electroporated into 129/Sv derived embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts and the resulting chimeric males were bred to 129/Sv females. The donating investigator reports that heterozygotes were backcrossed to 129/Sv for more than ten generations. Upon arrival at The Jackson Laboratory, mutant mice were bred with 129S1/SvImJ inbred mice (Stock No. 002448) for at least one generation to establish the colony.

A 27 SNP (single nucleotide polymorphism) panel analysis performed by The Jackson Laboratory revealed 9 of 27 markers (on nine different chromosomes) that were not 129 allele-type. These data suggest C57BL/6 (and perhaps other) genetic contamination prior to arrival at The Jackson Laboratory.

Allele

Symbol: Nphs1^tm1Rkl
Name: targeted mutation 1, Raghu Kalluri
MGI accession ID: MGI:2386960
Generation method: Targeted
Attributes: Reporter; Null/Knockout
Marker symbol: Nphs1
Marker name: nephrosis 1, nephrin
Chromosome: 7
Strain of origin: 129/Sv
Expressed genes: GFP,Green Fluorescent Protein,
Site of expression: GFP is detected in glomeruli.
Molecular note: 34 bp surrounding the translational start codon in exon 1 (-1 through +33) were replaced with a GFP-neo cassette inserted via homologous recombination. Expression of GFP was observed in both homozygous and heterozygous mutant mice.
General note: Immunohistochemical and western blot analyses of kidneys of homozygous newborn mice demonstrated absence of nephrin protein. No alteration was observed in expression of any glomerular basement membrane (GBM) or glomerular epithelial slit diaphragm (GESD) protein other than nephrin; proteins analyzed included integrin alpha3, podocin, alpha actinin 4, CD2AP, synaptopodin, nephronectin and type IV collagens alpha3, alpha4 and alpha5. (J:78616)