TPCN1 and mucolipidosis type IV: Perinuclear lysosome redistribution was seen in cells overexpressing TRPML1-L106P (a mutant associated with mucolipidosis type IV, an autosomal recessive lysosomal storage disorder) [29], TPCN1, and TPCN2, but not with wild-type TRPML1, when treated with P4 (S5E and S5F Fig).