Cover legend: High-magnification image of the granule cell layer of the developing dentate gyrus showing expression of a novel late-phase transcriptional regulator of dentate granule neuron maturation, Krüppel-like factor-9 (Klf-9) and the mature neuronal marker calbindin. Klf-9 and calbindin are are not expressed in immature neurons (blue) that reside in the inner half of the developing dentate gyrus. For more information, see the article by Scobie et al. in this issue (see pages 9875–9887).