Fig. 6

TRPML1 mediates greater Zn²⁺ release and less Ca²⁺ release in neurites than in the soma. Average traces (±s.e.m.) from soma (black) or neurites (red) of primary rat hippocampal neurons co-expressing a mCherry-TRPML1 and GZnP3, b expressing GZnP3-TRPML1, or c co-expressing mCherry-TRPML1 and GZnP3-Rab7a. d Mean integrated GZnP3 signal (±s.e.m.) 300 s after ML-SA1 addition between soma (dark) and neurites (light) for GZnP3 (soma, n = 10; neurites, n = 70 puncta), GZnP3-TRPML1 (soma, n = 48 puncta; neurites, n = 54 puncta), and GZnP3-Rab7a (soma, n = 62 puncta; neurites, n = 28 puncta). One-tailed Student’s t-tests. Average traces (±s.e.m.) from soma (black) or neurites (red) of primary rat hippocampal neurons e co-expressing mCherry-TRPML1 and GCaMP5, f expressing GCaMP5-TRPML1, or g co-expressing GCaMP5-Rab7a and mCherry-TRPML1. h Mean integrated GCaMP5 signal (±s.e.m.) 60 s after ML-SA1 addition between soma (dark) and neurites (light) for GCaMP5 (soma, n = 8; neurites, n = 68 puncta), GCaMP5-TRPML1 (soma, n = 30 puncta; neurites, n = 66 puncta), and GCaMP5-Rab7a (soma, n = 25 puncta; neurites, n = 42 puncta). One-tailed Student’s t-tests. i Average traces (±s.e.m.) from soma (black) and neurites (red) of primary rat hippocampal neurons co-expressing GZnP3-Rab7a and mCherry-TRPML1 pretreated with 200 µM GPN (magenta bar). j Mean integrated GZnP3-Rab7a signal (±s.e.m.) 300 s after ML-SA1 addition to neurons pretreated with GPN between soma (dark) and neurites (light) (soma, n = 41 puncta; neurites, n = 59 puncta). 50 µM ML-SA1 (black arrow), 100 µM TPEN (white arrow), 10 mM CaCl₂ (gray arrow). One-tailed Student’s t-test. ****p < 0.0001, **p < 0.01, *p < 0.05, n.s. not significant. p-values listed in italics above corresponding comparisons where applicable. S, soma. N, neurites. Source data are provided as a Source Data file