Cover legend: Murine Moloney leukemia virus mediated labeling of mitochondria (green) in adult-generated neurons (red) in the mouse hippocampal dentate gyrus. Dentate granule neurons are labeled with calbindin (magenta). Extensive mitochondrial biogenesis and redistribution accompany neuronal development and influence maturation in neurogenesis in adult hippocampus. For more information, see the article by Steib et al. (pages 6624–6633).