Leucine-rich repeat kinase 2 regulates tau phosphorylation through direct activation of glycogen synthase kinase-3β

Area of Science:

• Neuroscience
• Molecular Biology
• Cell Biology

Background:

• Leucine-rich repeat kinase 2 (LRRK2) is implicated in autosomal-dominant Parkinson's disease (PD).
• LRRK2's role in tau phosphorylation, a hallmark of neurodegenerative diseases, is under investigation.

Purpose of the Study:

• To investigate the direct interaction between LRRK2 and GSK-3β.
• To determine if LRRK2 influences GSK-3β kinase activity and tau phosphorylation.
• To elucidate the cellular functions regulated by the LRRK2-GSK-3β-tau pathway.

Main Methods:

• Co-immunoprecipitation assays to detect LRRK2-GSK-3β interaction.
• In vitro kinase assays to measure GSK-3β activity.
• Western blot analysis to assess tau phosphorylation at Ser396 in SH-SY5Y cells.

Main Results:

• LRRK2 directly associates with GSK-3β.
• This interaction significantly enhances the kinase activity of GSK-3β.
• LRRK2 activation of GSK-3β leads to increased tau phosphorylation at Ser396 in neuronal cells.

Conclusions:

• LRRK2 acts as a novel enhancer of GSK-3β activity.
• The LRRK2-GSK-3β pathway regulates tau phosphorylation, impacting neurite outgrowth and axonal transport.
• LRRK2-mediated tau phosphorylation may contribute to early pathological changes in Parkinson's disease.