B6.129P2-Epb42^tm1Llp/LlpJ

Stock number: 003947
Product name: 4.2-
Research areas: Developmental Biology Research, Hematological Research, Internal/Organ Research, Research Tools

Description

These 4.2- knock-out mice exhibit spherocytosis with reduction of red blood cell counts and hematocrits. They are suitable for use in applications related to the study of hereditary spherocytosis.

Detailed description

4.2- knock-out mice have a neo cassette replacing exons 4-8 of the erythrocyte membrane protein band 4.2 (Epb42) gene. Homozygotes have mild hereditary spherocytosis with significant reduction of red blood cell counts and hematocrits. There is a reduction of the mean corpuscular volume, increase in mean corpuscular hemoglobin concentration, and an approximately 2 fold increase in the percentage of reticuloctyes and spleen weight, but white blood cell counts are normal. Red blood cell membranes are deficient in band 3, although the membrane skeleton appears qualitatively normal by electron microscopy. Red blood cells of homozygotes also have increased K⁺ and decreased Na⁺ resulting in red blood cell dehydration. Heterozygotes have both normal and intermediate, cup-shaped red blood cells with a lower than normal deformability index, but not as low as in homozygotes.

Development

In these 4.2- mice, exons 4-8 of the erythrocyte membrane protein band 4.2 (Epb42) gene were replaced with a neomycin selection cassette. This targeted mutation was generated in 129P2/OlaHsd derived E14 ES cells and the male chimera was bred to a C57BL/6J female (Stock No. 000664). This mutation was later backcrossed onto the C57BL/6J background and in 2001 embryos were generated for cryopreservation from homozygous females and males at generation F3N13. In 2022, cryopreserved embryos were recovered and homozygous sperm was frozen for cryopreservation restock at generation N13.

Allele

Symbol: Epb42^tm1Llp
Name: targeted mutation 1, Luanne L Peters
MGI accession ID: MGI:2182816
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Epb42
Marker name: erythrocyte membrane protein band 4.2
Chromosome: 2
Strain of origin: 129P2/OlaHsd
Molecular note: Sequence from exons 4 through 8 was replaced with a neomycin selection cassette. Northern blot analysis of total reticulocyte RNA and RNase protection assays of nonerythroid tissue samples did not detect message encoded by the targeted allele. Protein was determined to be absent in erythroid cells from homozygous mutant mice via Western blot analysis and Coomassie blue staining.