Born to Stay Together For as many neurons as there are in the brain, there are many more astrocytes. These backstage workers perform a variety of functions, such as sustaining the blood-brain barrier and providing a stabilized environment for neurons. Diversity of astrocyte function is reflected in different molecular expression profiles. Tsai et al. (p. 358 , published online 28 June) selectively labeled astrocytes that originated from different domains of the mouse spinal cord and found that not all astrocytes are created equal: Neighborhoods of astrocytes were defined by shared birthplaces.

Regional Astrocyte Allocation Regulates CNS Synaptogenesis and Repair