miRNA expression in fast and slow skeletal muscle of wild type and SOD1-G93A mice

Amyotrophic lateral sclerosis (ALS) is a lethal motor neuron disease that progressively debilitates neuronal cells that control voluntary muscle activity. In a mouse model of ALS that expresses mutated human superoxide dismutase 1 (SOD1-G93A) skeletal muscle is one of the tissues affected early by mutant SOD1 toxicity. Fast-twitch and slow-twitch muscles are differentially affected in ALS patients and in the SOD1-G93A model, fast-twitch muscles being more vulnerable. We used miRNA microarrays to investigate miRNA alterations in fast-twitch (EDL) and slow-twitch (soleus) skeletal muscles of symptomatic SOD1-G93A animals and their age-matched wild type littermates. At age of 90 days RNA was extracted from extensor digitorum longus (EDL) and soleus (SOL) muscles of male SOD1-G93A animals and their age-matched wild type male littermates. RNA was hybridized on Affymetrix Multispecies miRNA-2_0 Array.