Stargazin-like γ-subunit proteins are surrounded by controversy: whereas they were previously thought to be subunits of Ca2+ channels, they are now widely accepted to belong to a group of transmembrane AMPA receptor regulatory proteins (TARPs). In addition, their cellular roles are still largely unclear. In their study on p. 2049, Annette Dolphin and colleagues now provide evidence that stargazin-like γ-subunit proteins have a role in endosomal trafficking and neurite outgrowth in neuronal cells. The authors show that, in sympathetic cervical ganglion neurons, the stargazin-like γ7 subunit (γ7) localises to small vesicular organelles. These vesicles primarily move in a retrograde direction and do not contain markers for the ER, Golgi, mitochondria, lysosomes or late endosomes. Instead, vesicular γ7 colocalises with the early-endosome marker EEA1 and the nerve growth factor receptor TrkA, suggesting it is a component of signalling endosomes. Furthermore, in cultured neuronal cells, knockdown of endogenous γ7 with small hairpin RNA decreases neurite length. In combination with the previous observation that transport of activated growth factor receptors to the neuronal cell body is essential for neurite outgrowth, these results suggest that the presence of γ7 in signalling endosomes is important in the regulation of this process.