Lysosomal Ca2+ homeostasis is affected in several lysosomal disorders, including CLN3 disease46 and, while Cln7 is not likely to be a Ca2+ channel, it will be interesting to ask if changes to Ca2+ accompany, and potentially underpin, the loss of post-synaptic TORC activity in Cln7 mutants, as they appear to pre-synaptically in Trmpl mutants20. This evidence concerns the gene MFSD8 and lysosomal storage disease.