Source: Rockefeller University
Date: August 25, 2008
Summary:
Adult stem cells are not pampered pushovers. O'Reilly et al. report that certain stem cells take charge of their surroundings, molding their environment to control their division and differentiation. Some stem cells are cosseted like newborns. Neighboring cells cradle them in a structure called the niche. The niche not only nurtures its charges, it also dictates their behavior, determining whether they reproduce and specialize. The standard view is that the niche shapes stem cells, not vice versa.
O'Reilly et al. found evidence for more active stem cells while studying how the cells anchor themselves in the Drosophila ovary. Previous work indicated that ovary stem cells attach to the niche through the protein E-cadherin. O'Reilly et al. tested whether the stem cells also depend on integrins, cell surface proteins that link molecules in the extracellular matrix to the cytoskeleton. They found that follicle stem cells (FSC)—one type of ovary stem cell—drifted away from their niche when they carried mutant integrins.
