Familial knockin mutation of LRRK2 causes lysosomal dysfunction and accumulation of endogenous insoluble α-synuclein in neurons

Jason Schapansky, Saurabh Khasnavis, Mark P. DeAndrade, Jonathan D. Nardozzi, Samuel R. Falkson, Justin D. Boyd, John B. Sanderson, Tim Bartels, Heather L. Melrose, Matthew J. LaVoie

Research output: Contribution to journalArticlepeer-review

36 Scopus citations

Abstract

Missense mutations in the multi-domain kinase LRRK2 cause late onset familial Parkinson's disease. They most commonly with classic proteinopathy in the form of Lewy bodies and Lewy neurites comprised of insoluble α-synuclein, but in rare cases can also manifest tauopathy. The normal function of LRRK2 has remained elusive, as have the cellular consequences of its mutation. Data from LRRK2 null model organisms and LRRK2-inhibitor treated animals support a physiological role for LRRK2 in regulating lysosome function. Since idiopathic and LRRK2-linked PD are associated with the intraneuronal accumulation of protein aggregates, a series of critical questions emerge. First, how do pathogenic mutations that increase LRRK2 kinase activity affect lysosome biology in neurons? Second, are mutation-induced changes in lysosome function sufficient to alter the metabolism of α-synuclein? Lastly, are changes caused by pathogenic mutation sensitive to reversal with LRRK2 kinase inhibitors? Here, we report that mutation of LRRK2 induces modest but significant changes in lysosomal morphology and acidification, and decreased basal autophagic flux when compared to WT neurons. These changes were associated with an accumulation of detergent-insoluble α-synuclein and increased neuronal release of α-synuclein and were reversed by pharmacologic inhibition of LRRK2 kinase activity. These data demonstrate a critical and disease-relevant influence of native neuronal LRRK2 kinase activity on lysosome function and α-synuclein homeostasis. Furthermore, they also suggest that lysosome dysfunction, altered neuronal α-synuclein metabolism, and the insidious accumulation of aggregated protein over decades may contribute to pathogenesis in this late-onset form of familial PD.

Original languageEnglish (US)
Pages (from-to)26-35
Number of pages10
JournalNeurobiology of Disease
Volume111
DOIs
StatePublished - Mar 2018

Keywords

  • LRRK2
  • Lysosome
  • Parkinson's disease
  • Tau
  • Tau phosphorylation
  • α-Synuclein

ASJC Scopus subject areas

  • Neurology

Fingerprint Dive into the research topics of 'Familial knockin mutation of LRRK2 causes lysosomal dysfunction and accumulation of endogenous insoluble α-synuclein in neurons'. Together they form a unique fingerprint.

Cite this