Lrrk2 (Dardarin) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
LRRK2 (Leucine-Rich Repeat Kinase 2), also known as dardarin, is a large multi-domain protein with both GTPase and kinase activities. It is one of the most common genetic causes of Parkinson's disease, with the G2019S mutation being the most prevalent known genetic determinant of sporadic PD. LRRK2 is a major therapeutic target for disease-modifying PD treatments.
LRRK2 is a 2,527-amino acid protein with multiple functional domains:
- ARM domain (Armadillo repeats): Protein-protein interactions
- ANK domain (Ankyrin repeats): Substrate recognition
- LRR domain (Leucine-rich repeats): Dimerization and localization
- ROC domain (Ras of complex proteins): GTPase activity
- COR domain (C-terminal of ROC): Kinase regulation
- Kinase domain: Ser/Thr protein kinase activity
- WD40 domain: Protein interactions
¶ Domain Architecture
N-terminus → ARM → ANK → LRR → ROC → COR → Kinase → WD40 → C-terminus
The protein functions as a dimer, with both kinase and GTPase activities regulated through intramolecular interactions.
¶ Function and Mechanism
The ROC domain binds GTP/GDP:
- Acts as a molecular switch
- Regulates kinase activity through ROC-COR domain interactions
- Autophosphorylation at Ser1072 and Ser2035
LRRK2 phosphorylates multiple substrates:
- Rab proteins (Rab3, Rab8, Rab10, Rab12, Rab35): Regulates vesicle trafficking
- MAPKKK family: Activates downstream signaling cascades
- 自身 (Autophosphorylation): Ser1292 is the major autophosphorylation site
LRRK2 intersects multiple cellular pathways:
- MAPK/ERK pathway: Neuronal survival and plasticity
- PI3K/AKT pathway: Cell survival signaling
- Wnt signaling: Developmental and regenerative processes
- Inflammatory pathways: Microglial activation
LRRK2 mutations cause autosomal dominant PD:
- G2019S: Most common (~5% of familial PD, ~1% sporadic PD)
- R1441C/G/H: Second most common
- N1437H: Associated with reduced penetrance
- I2020T: Found in Japanese families
LRRK2 mutations lead to:
- Increased kinase activity: G2019S increases activity ~2-3 fold
- Dysregulated vesicle trafficking: Rab phosphorylation disrupts endolysosomal function
- Synaptic dysfunction: Altered neurotransmitter release
- Inflammation: Microglial activation and neuroinflammation
- Expressed in dopaminergic neurons, cortex, hippocampus
- Localizes to membranes, synaptic vesicles, mitochondria
- Critical for neuronal development and maintenance
Multiple LRRK2 inhibitors in development:
- DNL151 (Denali): CNS-penetrant, Phase 1/2
- BIIB122 (Biogen/Denali): Previously called DNL202
- PF-06447475 (Pfizer): Preclinical
- Achieving brain penetration
- Balancing efficacy with safety (lung and kidney toxicity)
- Biomarker development for patient selection
- Phospho-Rab10: Blood/CSF biomarker for LRRK2 activity
- Neuroimaging: PET ligands in development
- [LRRK2 Gene--TEMP--/genes)--FIX--
- [Parkinson's Disease--TEMP--/diseases)--FIX--
- [LRRK2 Pathway--TEMP--/mechanisms)--FIX--
- [Dopaminergic Neurons--TEMP--/cell-types)--FIX--
- [LRRK2 G2019S--TEMP--/diseases)--FIX--
The study of Lrrk2 (Dardarin) has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
- Zimprich et al., LRRK2 mutations cause Parkinson's disease (2004)
- Paisan-Ruiz et al., LRRK2 identified as PD gene (2004)
- Cookson, LRRK2 function in the brain (2010)
- Steger et al., LRRK2 phosphorylates Rab proteins (2016)
- Di Maio et al., LRRK2 in mouse models (2018)
- Muda et al., LRRK2 inhibitors in clinical development (2023)
- Ito et al., LRRK2 and neuroinflammation (2022)
- Blandini et al., LRRK2 as therapeutic target (2019)