Previews. Niche today, gone tomorrow--progenitors create short-lived niche for stem cell specification.

Establishing tissue-specific adult stem cells during organogenesis is important for maintenance of tissue homeostasis throughout the lifetime of the organism. In a recent study in Science, Mathur et al. (2010) describe how progenitor cells in the Drosophila larval midgut create a temporary niche to maintain stem cell fate during development. 2010 Elsevier Inc. All rights reserved.