STOCK Tg(En2-cre)22Alj/J

Stock number: 008852
Research areas: Neurobiology Research, Research Tools

Description

These En2-cre line 22 transgenic mice (also called En2cre-22, En2cre line Tg22, or En2-cre tg-22) have the mouse engrailed 2 (En2) promoter/enhancer elements directing expression of Cre recombinase to a subset of En2-expressing cells; including the embryonic midbrain-hindbrain (mesencephalon-metencephalon) constriction region of the developing brain that gives rise to the posterior midbrain and medial cerebellum.

Detailed description

En2-cre line 22 transgenic mice (also called En2cre-22, En2cre line Tg22, or En2-cre tg-22) are viable and fertile, with expression of Cre recombinase directed to the embryonic midbrain-hindbrain constriction region by mouse engrailed 2 promoter/enhancer elements. Specifically, whole-mount RNA in situ hybridization with a Cre recombinase antisense probe shows cre expression in a narrow dorsal domain surrounding the midbrain-hindbrain junction at embryonic day 9.5 (E9.5). When these En2-cre line 22 transgenic mice are bred with mice containing loxP-flanked sequences, Cre-mediated recombination will result in deletion of the floxed sequences in a subset of En2-expressing tissues of the offspring; including the embryonic midbrain-hindbrain (mesencephalon-metencephalon) constriction region of the developing brain that gives rise to the posterior midbrain and medial cerebellum.

When the donating investigator bred En2-cre line 22 transgenic mice with lacZ reporter mice, adult brain regions in the double transgenic offspring showed evidence of embryonic Cre recombinase activity; these include a) part of the midbrain structure responsible for visual processing (superior colliculus), much of the region responsible for auditory processing (inferior colliculus), and some regions responsible for homeostatic and reflexive pathways (tegmentum); b) some anterior hindbrain structures responsible for integration of sensory perception, coordination and motor control (primarily the medial cerebellum); and c) forebrain structures responsible for short term memory and spatial navigation (hippocampus).

Development

The En2-cre transgene was designed with the mouse engrailed 2 enhancer/promoter sequences (2.6 kbp enhancer fragment and 2.3 kbp minimal promoter sequences) upstream of a Cre recombinase cDNA sequence and followed by a metallothionein polyadenylation signal. This transgene was injected into CD1 zygotes. Founder mice were bred to CD1 outbred mice to establish founder line 22. These En2-cre line 22 transgenic mice (also called En2cre-22, En2cre line Tg22, or En2-cre tg-22) were bred to Swiss Webster outbred mice for many generations prior to arrival at The Jackson Laboratory Repository. Upon arrival, En2cre-22 transgenic mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony at The Jackson Laboratory Repository.

Allele

Symbol: Tg(En2-cre)22Alj
Name: transgene insertion 22, Alexandra L Joyner
MGI accession ID: MGI:2450322
Generation method: Transgenic
Attributes: Recombinase-expressing
Marker symbol: Tg(En2-cre)22Alj
Marker name: transgene insertion 22, Alexandra L Joyner
Chromosome: UN
Strain of origin: CD-1
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: The En2 promoter directs expression in the embryonic midbrain-hindbrain constriction region, the cerebellum, tectum, hippocampus and tegmentum.
Molecular note: The transgenic constuct contained a cre recombinase gene adjoined to an En2 minimal promoter and enhancer. The En2 promoter directs expression in the embryonic midbrain-hindbrain constriction region, the cerebellum, tectum, hippocampus and tegmentum.