B6(Cg)-Meis1^em1Bcca/AkarJ

Stock number: 038030
Product name: MEIS1-EGFP
Research areas: Cancer Research, Developmental Biology Research, Hematological Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

MEIS1-EGFP mice contain a CRISPR/Cas9-generated insertion of a GFP-P2A-HA immediately downstream of the endogenous Meis1 translational start site (TSS). These mice may be useful for tracking Meis1-expressing hematopoietic cells and for exploring MEIS1 function and regulation during normal and leukemic hematopoiesis.

Detailed description

MEIS1-EGFP mice contain a CRISPR/cas9 generated insertion of a GFP-P2A-HA immediately 5’ of the endogenous Meis homeobox 1 (Meis1) translational start site (TSS). Specifically, the construct contains (from 5’ to 3’) GFP, a P2A ribosomal skip cleavage peptide sequence, and a hemagglutinin (HA) epitope tag. The insertion of the GFP-P2A-HA sequence does not affect endogenous protein expression.

In these mice, MEIS1-HA is expressed as a fusion protein, while GFP is generated as an independent protein due to the presence of the P2A peptide sequence. Meis1 encodes a HOX transcription cofactor which is a critical regulator of hematopoiesis, megakaryocyte lineage development and vascular patterning. Overexpression of MEIS1 has been implicated in a wide range of leukemias. These mice may be useful for tracking Meis1-expressing hematopoietic cells and for exploring MEIS1 function and regulation during normal and leukemic hematopoiesis.

Heterozygous mice are viable and fertile. The donating investigator has not attempted to make a homozygous colony.

GFP fluorescence is detectable by FACS analysis and direct microscopy.

Development

Guide RNA (caccgAGAGAGGCCGATGGCGCAAA and aaacTTTGCGCCATCGGCCTCTCTc) were designed to introduce a green fluorescent protein-P2A-HA sequence (GFP-P2A-HA) in-frame immediately 5’ of the endogenous Meis homeobox 1 (Meis1) translational start site (TSS). The guide RNA, donor plasmid, and the cas9 nuclease were electroporated into C57BL/6N-derived C2 embryonic stem (ES) cells. A correctly targeted ES cell, with one insertion site, was aggregated with 8-cell stage embryos from B6(Cg)-Tyr^c-2J/J mice (Stock No. 000058). The resultant blastocysts were then transplanted into a pseudopregnant CD-1 mouse. Correctly targeted pups were identified by sequencing and PCR and resulting MEIS1-EGFP males were bred to C57BL/6J females (Stock No. 000664). Off-target CRISPR changes were removed. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes.

Allele

Symbol: Meis1^em1Bcca
Name: endonuclease-mediated mutation 1, BC Cancer Angency
MGI accession ID: MGI:5897822
Generation method: Endonuclease-mediated
Attributes: Reporter; Epitope tag
Marker symbol: Meis1
Marker name: Meis homeobox 1
Marker synonyms: C530044H18Rik
Chromosome: 11
Strain of origin: C57BL/6NTac
Molecular note: CRISPR/Cas9 technology inserted a GFP-P2A-HA tag at the translational start site.