Figure 1.
The C. elegans gonad forms a tube that is closed at the distal end, where stem cells are located, and open at the proximal end (not shown) from which differentiated gametes exit. The Distal Tip Cell (DTC) acts as a stem niche, at least in part by expressing Notch ligands. The DTC extends processes that start growing from the last larval stage (L4). These processes tightly intercalate between germ cells, especially in the distal region where stem cells are located, and in mature adults extend past the mitotic zone in which cells are proliferating.
