Activity Regulated Cytoskeleton Associated Protein (ARC)

The deduced 460-amino acid protein shares significant similarity with rat Arc. Northern blot analysis detected low ARC expression in heart, brain, lung, skeletal muscle, pancreas, prostate, and testis, weak expression in small intestine, colon, and peripheral blood leukocytes, and no expression in other tissues examined.Rat neurons express Arc at low levels under resting conditions, but Arc mRNA is rapidly induced and delivered into dendrites following synaptic activity. Arc assembled into particles that moved independently, bidirectionally, and intermittently with velocities consistent with both actin-based and microtubule-based transport. Rapidly translocating Arc mRNA particles sometimes reversed direction and decreased velocity just before stopping, suggesting that local signals regulate Arc mRNA targeting.