Cover legend: Differential expression of collapsin response mediator proteins CRMP2 and CRMP5 in embryonic mouse hippocampal neurons cultured for 1–6 d (counterclockwise from upper right). CRMP2 (red), which promotes growth, is expressed in axon and dendrites at all stages of development, whereas expression of CRMP5 (green), which inhibits dendrite growth, varies, with peaks at days 3 and 6. These differences in expression help regulate the development of neuronal polarity. For more information, see the article by Brot et al. in this issue (pages 10639–10654).