During stem cell divisions, mitotic microtubules do more than just segregate the chromosomes. They also determine whether a cell divides virtually symmetrically or asymmetrically by establishing spindle orientation and the plane of cell division. This can be decisive for the fate of the stem cell progeny. Spindle defects have been linked to neurodevelopmental disorders, yet the role of spindle ...

Stem cells have the unique ability to both maintain the stem cell population via self-renewal and give rise to differentiated cells. The balance between these options is very delicate and important for the short- and long-term maintenance of tissue homeostasis in an organism. Pathways involved in integrating environmental cues and in directing energy metabolism play an important role in the fat...

Stem cells have the capacity to differentiate into various lineages, and the ability to reliably direct stem cell fate determination would have tremendous potential for basic research and clinical therapy. Nanotopography provides a useful tool for guiding differentiation, as the features are more durable than surface chemistry and can be modified in size and shape to suit the desired applicatio...

Recreating heterotypic cell-cell interactions in vitro is key to dissecting the role of cellular communication during a variety of biological processes. This is especially relevant for stem cell niches, where neighbouring cells provide instructive inputs that govern cell fate decisions. To investigate the logic and dynamics of cell-cell signalling networks, we prepared heterotypic cell-cell int...

The conventional model of intestinal epithelial architecture describes a unidirectional tissue organizational hierarchy with stem cells situated at the crypt base and daughter cells proliferating and terminally differentiating as they progress along the vertical (crypt-luminal) axis. In this model, the fate of a cell that has left the niche is determined and its lifespan limited. Evidence is ac...

Establishing and maintaining cell fate in the right place at the right time is a key requirement for normal tissue maintenance. Stem cells are at the core of this process. Understanding how stem cells balance self-renewal and production of differentiating cells is key for understanding the defects that underpin many diseases. Both, external cues from the environment and cell intrinsic mechanism...

In cycling tissues that exhibit high turnover, tissue maintenance and repair are coordinated by stem cells. But, how frequently stem cells are replaced following differentiation, aging or injury remains unclear. By drawing together the results of recent lineage-tracing studies, we propose that tissue stem cells are routinely lost and replaced in a stochastic manner. We show that stem cell repla...

epilepsy is one of the most common neuroinflammatory disorders that affect more than 50 million people worldwide. excessive electrical discharges in neurons following neural cell damage or loss leads to recurrent seizures, which are described as epilepsy. one of the most common and difficult to treat types of epilepsy is temporal lobe epilepsy (tle), which results from hippocampal sclerosis. cu...

Cell fates are determined by specific transcriptional programs. Here we provide evidence that the transcriptional coactivator, Mediator 1 (Med1), is essential for the cell fate determination of ectodermal epithelia. Conditional deletion of Med1 in vivo converted dental epithelia into epidermal epithelia, causing defects in enamel organ development while promoting hair formation in the incisors....

During development, many neural stem cells "age" as they sequentially generate distinct neuronal or glial cell types. In this issue, Maurange et al. (2008) now identify the temporal control factors in Drosophila neural stem cells (neuroblasts) that regulate the fate of stem cell progeny and signal the end of stem cell proliferation.