Neurogenic niches in the adult mammalian brain are composed of heterogeneous populations of neural stem cells. In this issue of Neuron, Codega et al. (2014) isolate quiescent neural stem cells from the adult subventricular zone and demonstrate their stem cell characteristics.

To preserve tissue integrity during the structural rearrangements that occur during central nervous system (CNS) development, an intricate balance between extracellular matrix (ECM) synthesis and degradation must be maintained. The matrix metalloproteinases (MMPs) are believed to be the main mediators of ECM degradation. Because MMPs function in the turnover of a broad-spectrum of ECM proteins ...