Our understanding of the balance between stem cell proliferation and differentiation hinges on our knowledge of stem cell niches. Stem cell systems require an interaction between the niche and the adjacent stem cells for maintenance of this balance. The somatic distal tip cell (DTC) functions as the germline stem cell niche in the C. elegans gonad. It acts via GLP-1/Notch signaling to provide cues to its adjacent stem cell pool. Here we report a novel phenotype associated with the Derlin protein, DER-1 (CUP-2). As worms that are mutant for
cup-2 age, the DTC is displaced proximally along the gonad arm. With the movement of the DTC the stem cell pool concurrently moves and therefore the displaced DTC is still functional. Currently, we are exploring the two primary roles of
cup-2, endoplasmic reticulum associated degradation (ERAD) and endocytosis, for their function in DTC anchorage. Also, we are determining if
cup-2's function is required in either the DTC, the germline, or both, for adhesion (Linden et al., 2017). This investigation of CUP-2 may help us understand how the DTC is normally held at the distal end of the gonad, and how its displacement affects germline stem cells.