Q&A: Trash talk: disposal and remote degradation of neuronal garbage

Caenorhabditis elegans neurons have recently been found to throw out cellular debris for remote degradation and/or storage, adding an “extracellular garbage elimination” option to known intracellular protein and organelle degradation pathways. This Q&A describes initial insights into the biology of seemingly selective protein and organelle elimination by challenged neurons, highlighting mysteries of how garbage is distinguished and sorted in the sending neuron, how the garbage-filled “exophers” appear to elicit degradative responses as they transit neighboring tissue, and how non-digestible materials get thrown out of cells again via processes that may be highly relevant to human neurodegenerative disease mechanisms.