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Dysregulation of lysosomal morphology by pathogenic LRRK2 is corrected by TPC2 inhibition.

ABSTRACT: Two-pore channels (TPCs) are endolysosomal ion channels implicated in Ca(2+) signalling from acidic organelles. The relevance of these ubiquitous proteins for human disease, however, is unclear. Here, we report that lysosomes are enlarged and aggregated in fibroblasts from Parkinson disease patients with the common G2019S mutation in LRRK2. Defects were corrected by molecular silencing of TPC2, pharmacological inhibition of TPC regulators [Rab7, NAADP and PtdIns(3,5)P2] and buffering local Ca(2+) increases. NAADP-evoked Ca(2+) signals were exaggerated in diseased cells. TPC2 is thus a potential drug target within a pathogenic LRRK2 cascade that disrupts Ca(2+)-dependent trafficking in Parkinson disease.

SUBMITTER: Hockey LN

PROVIDER: S-EPMC4294771 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Dysregulation of lysosomal morphology by pathogenic LRRK2 is corrected by TPC2 inhibition.

Hockey Leanne N LN Kilpatrick Bethan S BS Eden Emily R ER Lin-Moshier Yaping Y Brailoiu G Cristina GC Brailoiu Eugen E Futter Clare E CE Schapira Anthony H AH Marchant Jonathan S JS Patel Sandip S

Journal of cell science 20141121 2

Two-pore channels (TPCs) are endolysosomal ion channels implicated in Ca(2+) signalling from acidic organelles. The relevance of these ubiquitous proteins for human disease, however, is unclear. Here, we report that lysosomes are enlarged and aggregated in fibroblasts from Parkinson disease patients with the common G2019S mutation in LRRK2. Defects were corrected by molecular silencing of TPC2, pharmacological inhibition of TPC regulators [Rab7, NAADP and PtdIns(3,5)P2] and buffering local Ca(2+ ...[more]

PMID: 25416817

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