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Mucolipin-1 is a lysosomal membrane protein required for intracellular lactosylceramide traffic.

ABSTRACT: Mucolipin-1 is a membrane protein encoded by the gene MCOLN1, mutations in which result in the lysosomal storage disorder mucolipidosis type IV (MLIV). Efficient lysosomal targeting of mucolipin-1 requires di-leucine motifs in both the N-terminal and the C-terminal cytosolic tails. We have shown that aberrant lactosylceramide trafficking in MLIV cells may be rescued by wild-type mucolipin-1 expression but not by mucolipin-1 mistargeted to the plasma membrane or by lysosome-localized mucolipin-1 mutated in its predicted ion pore-selectivity region. Our data demonstrate that the correct localization of mucolipin-1 and the integrity of its ion pore are essential for its physiological function in the late endocytic pathway.

SUBMITTER: Pryor PR

PROVIDER: S-EPMC7212080 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Mucolipin-1 is a lysosomal membrane protein required for intracellular lactosylceramide traffic.

Pryor Paul R PR Reimann Frank F Gribble Fiona M FM Luzio J Paul JP

Traffic (Copenhagen, Denmark) 20061001 10

Mucolipin-1 is a membrane protein encoded by the gene MCOLN1, mutations in which result in the lysosomal storage disorder mucolipidosis type IV (MLIV). Efficient lysosomal targeting of mucolipin-1 requires di-leucine motifs in both the N-terminal and the C-terminal cytosolic tails. We have shown that aberrant lactosylceramide trafficking in MLIV cells may be rescued by wild-type mucolipin-1 expression but not by mucolipin-1 mistargeted to the plasma membrane or by lysosome-localized mucolipin-1 ...[more]

PMID: 16978393

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