GFP:LC3-GAA-/- mice carry a null allele (neo inserted into exon 6) of Gaa (glucosidase, alpha, acid) and express an EGFP reporter fused to Map1lc3b (microtubule-associated protein 1 light chain 3 beta or LC3b). The reporter labels autophagosomes in a mouse model of glycogen storage disease type II (Pompe disease). This strain maybe useful in studies of lysosomal and autophagic abnormalities and lysosomal storage disorders.

129Sv

Muscle weakness and wasting at 7-9 months of age

Conditional phenotype: no

The GFP:LC3-GAA-/- strain was created in the laboratory of Dr. Nina Raben (NIAMS, NIH) by crossing mice the carrying Gaa^tm1Rabn allele and mice carrying Tg(CAG-EGFP/Map1lc3b)53Nmz allele. Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6NJ oocytes.

The Gaa targeting vector contains a loxP site in intron 5, a new termination codon, a new EcoRV site, a neomycin cassette and a second loxP in intron 6 of the Gaa (glucosidase, alpha, acid) gene. The construct was electroporated into 129X1/SvJ-derived RW-4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts and the resulting chimeric males were bred with C57BL/6 females.The strain was backcrossed to C57BL/6 for at least 5 generations.

The GFP:LC3 transgenic construct contains the widespread CAG promoter (cytomegalovirus immediate-early enhancer followed by a 1.3-kb DNA segment including the promoter, first exon and first intron of the chicken beta-actin gene, with the 3' splice junction sequence replaced by that of the rabbit hemoglobin beta gene) directing expression an EGFP reporter fused to the N-terminus of rat Map1lc3b (microtubule-associated protein 1 light chain 3 beta) followed by SV40 polyA sequence. The linearized construct was microinjected into the pronuclei of fertilized C57BL/6NCrj x BXDF1 fertilized eggs. Founder 53 was crossed to C57BL/6NCrj for at least 5 generations. Copy number was not determined. The transgene insertion site is located in the distal region of chromosome 2, 106 bp upstream of the Gm14314 locus.

GAA knockout and GFP:LC3-WT

The MMRRC Centers have developed a genetic QC pipeline using MiniMUGA array genotyping to provide additional information on strain backgrounds for MMRRC congenic and inbred strains. For more information on when data may be available, or to request genotyping for a strain of interest, please contact csmmrrc@jax.org. Older strains may not have this information.

Nina Raben-Belenky, M.D., NIH.