Stem Cell Niches
Though the concept of stem cell niche was prevailing in vertebrates, the first characterization of stem cell niche in vivo was figured out in drosophila germinal development. A stem-cell niche is an area of a tissue that provides a specific microenvironment, in which stem cells are present in an undifferentiated and self-renewable state. Cells of the stem-cell niche interact with the stem cells to take care of them or promote their differentiation. Characterization of these stem cell niches depends on the ability to identify stem cells in vivo in their normal setting. Through comparison of different stem cell systems, some themes emerge that indicate possible general characteristics of the relationship between stem cells and their supporting niche.