B6N.129-Ephb6^tm1Jwu/J

Stock number: 018163
Research areas: Cardiovascular Research, Research Tools

Description

Replacing exons 3-4 of Ephb6 with a GFP-neo cassette reduces T cell-mediated immune responses, and affects vascular smooth muscle cell contractility and blood pressure.

Detailed description

A GFP-neo cassette replaces exons 3-4, including the initiation sequence, of the Eph receptor B6 (Ephb6) gene, abolishing gene function. EPHB6 is a transmembrane cell surface receptor tyrosine kinase expressed on the surface of T cells, leukemic cells, vascular smooth muscle cells (VSMC), the adrenal gland medulla, skin, teeth, tongue and many brain regions. Homozygous Ephb6^-/- mice are viable and fertile. Decreased EPHB6 expression occurs in mature T cells. Weak GFP fluorescence, driven by the Ephb6 promoter, is visible on the surface of CD4⁺CD8⁺ DP, CD4⁺ SP, and CD8⁺ SP thymocytes from Ephb6^-/- mice. T cells from these mice show reduced expression of interleukin (IL)-2, IL-4, and interferon-γ, and have compromised responses upon activation. These mice also exhibit diminished responses to both delayed-type hypersensitivity and induced experimental autoimmune encephalitis (EAE). Small arteries from male Ephb6^-/- mice display reduced contractility, while small arteries from female and castrated male Ephb6^-/- mice show increased contractility. Male Ephb6^-/- mice present reduced 24-h urine catechoamine excresion. Male Ephb6^-/- mice present reduced 24-h urine catechoamine excresion. Levels return to normal following castration. Castrated Ephb6^-/- males have increased systolic and diastolic blood pressure.

Development

A targeting vector was designed to replace exon 3-4 of the Erythropoietin-producing hepatocyte (Eph) receptor B6 (Ephb6) gene with a green fluorescent protein (GFP)-neomycin cassette. The construct was electroporated into 129/Sv-derived embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6NCrl blastocysts and the resulting chimeric mice were bred to C57BL/6NCrl mice. These mice were backcrossed to C57BL/6NCrl mice for at least ten generations. Upon arrival at The Jackson Laboratory Repository, mice were bred to C57BL/6NJ inbred mice (Stock No. 005304) for at least one generation to establish the colony.

Allele

Symbol: Ephb6^tm1Jwu
Name: targeted mutation 1, Jiangping Wu
MGI accession ID: MGI:3522020
Generation method: Targeted
Attributes: Reporter; Null/Knockout
Synonyms: Eph6b^-
Marker symbol: Ephb6
Marker name: Eph receptor B6
Marker synonyms: Cekl; HEP; Mep
Chromosome: 6
Strain of origin: 129
Expressed genes: GFP,Green Fluorescent Protein,
Site of expression: Weak GFP fluorescence is visible on the surface of CD4+CD8+ DP, CD4+ SP, and CD8+ SP thymocytes.
Molecular note: A sequence from the ATG in exon 3 thru the 5' end of intron 4 ws replaced with a GFP-neo cassette. Mutants demonstrated no transcript expression but did express GFP driven by the endogenous promoter.