This image shows the expression of connexin 43 (Cx43, green) in the ependyma of the spinal cord of a neonatal mouse. Nuclei are stained with DAPI (blue). Communication among ependymal cells via gap junctions decreases in adulthood when the ependymal stem cell niche becomes quiescent but is restored after spinal cord injury suggesting a role of connexin signaling in the resumption of proliferation. For more information, see the article by Fabbiani, Reali, Valentín-Kahan et al. (pages 2246–2258).