Cover legend: This fluorescent image depicts a primary cultured motor neuron transfected with a fluorescent protein (shown in cyan) and stained with the F-actin binding protein phalloidin (shown in purple) and DNA dye DAPI (shown in green) highlighting the complex dendritic arbor and long axon in this high degree of morphological polarization. The spinal muscular atrophy (SMA) disease protein SMN facilitates the subcellular localization and local translation of mRNAs such as GAP43 along the long axonal processes. For more information, see the article by Fallini, Donlin-Asp et al. (pages 3811–3820).