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The inositol polyphosphate 5-phosphatase Ocrl associates with endosomes that are partially coated with clathrin.

ABSTRACT: The subcellular localization of Ocrl, the inositol polyphosphate 5-phosphatase that is mutated in Lowe syndrome, was investigated by fluorescence microscopy. Ocrl was localized to endosomes and Golgi membranes along with clathrin, giantin, the mannose 6-phosphate receptor, transferrin, and the early endosomal antigen 1 endosomal marker in fixed cells. The endosomal localization of Ocrl was confirmed by live-cell time-lapse microscopy in which we monitored the dynamics of Ocrl on endosomes. GST binding assays show that Ocrl interacts with the clathrin terminal domain and the clathrin adaptor protein AP-2. Our findings suggest a role for Ocrl in endosomal receptor trafficking and sorting.

SUBMITTER: Ungewickell A

PROVIDER: S-EPMC518786 | biostudies-other | 2004 Sep

REPOSITORIES: biostudies-other

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The inositol polyphosphate 5-phosphatase Ocrl associates with endosomes that are partially coated with clathrin.

Ungewickell Alexander A Ward Michael E ME Ungewickell Ernst E Majerus Philip W PW

Proceedings of the National Academy of Sciences of the United States of America 20040907 37

The subcellular localization of Ocrl, the inositol polyphosphate 5-phosphatase that is mutated in Lowe syndrome, was investigated by fluorescence microscopy. Ocrl was localized to endosomes and Golgi membranes along with clathrin, giantin, the mannose 6-phosphate receptor, transferrin, and the early endosomal antigen 1 endosomal marker in fixed cells. The endosomal localization of Ocrl was confirmed by live-cell time-lapse microscopy in which we monitored the dynamics of Ocrl on endosomes. GST b ...[more]

PMID: 15353600

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