The niche in single-cell technologies.

The niche is the microenvironment in which each cell exists and is able to keep its own peculiar characteristics. The importance of the niche has been intensively studied especially in the context of stem cells, as it is responsible for both the maintenance of stemness and activation of differentiation. In the past few years, a variety of single-cell technologies have shed light on the extraordinary variability that characterizes different stem cell populations both in vitro and in vivo, but in most cases positional information is lost. Recent developments of new technologies aim to integrate both the transcriptomic profiling of cells and their spatial location. In this review I will discuss the state of the art of these technologies and the integration with others approaches that will be important in the study of stem cell populations.