Melanoregulin is stably targeted to the melanosome membrane by palmitoylation

► Melanoregulin-GFP targets extensively to the limiting membrane of the melanosome. ► Endogenous melanoregulin also targets extensively to the melanosome. ► Melanoregulin targeting to melanosomes and lysosomes requires N-terminal cysteines. ► SDM, metabolic labeling and inhibitors show that melanoregulin is palmitoylated on these cysteines. ► FRAP shows that melanoregulin is stably targeted to the melanosome membrane.