VAMP7 and TYRP1, but not RAB38 and VARP, localize normally to melanosomes in BLOC-3–deficient cells. (a–z) BLOC-3–deficient melan-le (le; a–d, i–m, and s–v) and “rescued” melan-le cells stably expressing HA-HPS4 (le:HPS4; e–h, n–r, and w–z) were untreated (a–h) or transiently transfected with mCh-VAMP7 (red, i–z) and either GFP-RAB38 (green, i–r) or VARP-GFP (green, s–z), fixed 24 h (a–r) or 48 h (s–z) after transfection, and immunolabeled for LAMP2 (green, a–h) and/or TYRP1 (red, a–h; cyan, i–r) and analyzed by deconvolution immuno-FM. (a–h) Arrowhead points to a LAMP2-positive lysosome, and arrows show TYRP1-positive melanosomes. (i–r) Arrows show mCh-VAMP7 and TYRP1 colocalized to melanosomes visualized by BF. Note RAB38-GFP localization to melanosomes in le:HPS4 (n), but not in le (i). (s–z) Large arrowhead in le main panel (s) shows perinuclear accumulation of VARP-GFP. Arrowheads in insets show VARP-GFP puncta associated with melanosomes, and arrows point to melanosomes lacking VARP-GFP puncta. BF images in c, g, l, and q are pseudocolored blue in the merged images in d, h, m, and r. Insets, boxed regions magnified five times. Bars: (main) 10 µm; (insets) 2 µm.