Mice that are homozygous for the targeted mutant <i>Smn</i> allele and homozygous for the Tg(SMN2*delta7)4299Ahmb and Tg(SMN2)89Ahmb transgenes exhibit symptoms and neuropathology similar to patients afflicted with proximal spinal muscular atrophy (SMA). At birth, triple mutants are noticeably smaller than normal littermates. By day 5, signs of muscle weakness are apparent and become progressively more pronounced over the following week as the mice display an abnormal gait, shakiness in the hind limbs and a tendency to fall over. Mean survival is approximately 13 days. Immunocytochemical analysis indicates that dystrophin expression is normal, however fibers isolated from the gastrocnemius muscle of a 14 day old triple mutant clearly show evidence of atrophy.
These transgenic mice also express Enhanced Green Fluorescent Protein (EGFP) under the direction of the human S100 calcium-binding protein, beta (neural) promoter. Fluorescence is detected in Schwann cells at the neuromuscular junction.
EGFP expression is detected at birth and fluorescence is also detected in Schwann cells of the sternomastoid, soleus, extensor digitorum longus, triangularis sterni and diaphragm muscles, some astrocytes, Bergmann glia and a few muscle macrophages. Presence of the Tg(S100B-EGFP)1Wjt transgene does not change the phenotype.

This s100 GFP SMA delta 7 mutant mouse strain may be useful in studies for visualization and vital imaging of neuromuscular junction Schwann cells in the etiology and pathology of Spinal Muscular Atrophy.

Typically mice are recovered in 12-16 weeks. Contact Customer Service to place an order or for more information.

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