# ALPHA-SYNUCLEIN E46K Research Report **Protein:** ALPHA-SYNUCLEIN E46K **Variant:** E46K **UniProt ID:** P37840 **Disease Association:** Parkinson's disease **Report Generated:** 2026-05-26 03:47 UTC **AlphaFold Confidence (pLDDT):** 59.8% **Structure Folded:** 2026-05-14 --- ## Structure Summary Alpha-synuclein is a brain protein whose clumping causes Parkinson's disease, and the E46K mutation makes this clumping worse, leading to early-onset inherited Parkinson's. This analysis used AlphaFold2 to predict the structure of the E46K variant, but the overall low confidence score (59.8) indicates the protein is highly flexible and disordered, making it difficult to capture a single stable structure. The E46K mutation is classified as pathogenic by expert panels and has never been observed in healthy populations, confirming it directly causes disease. --- Alpha-synuclein is a small neuronal protein that normally helps regulate neurotransmitter release at synapses, but when it misfolds and aggregates into clumps called Lewy bodies, it causes Parkinson's disease [1]. The E46K mutation, where glutamic acid (E) is replaced by lysine (K) at position 46, is one of the rare genetic variants that cause early-onset familial Parkinson's disease. This mutation changes a negatively charged amino acid to a positively charged one in a critical region of the protein, which dramatically increases its tendency to aggregate and form toxic clumps [3]. ClinVar classifies E46K as pathogenic based on multiple expert submissions, and the complete absence of this variant in the gnomAD population database (which catalogs genetic variation in over 140,000 healthy individuals) strongly supports its disease-causing role. The AlphaFold2 structural prediction for E46K alpha-synuclein yielded an average confidence score (pLDDT) of 59.8, which falls well below the threshold of 70 typically considered reliable for structural interpretation. This low confidence reflects an intrinsic property of alpha-synuclein: it is an intrinsically disordered protein (IDP) that lacks a stable three-dimensional structure in its normal cellular state [5]. Instead of adopting a fixed shape, alpha-synuclein exists as an ensemble of rapidly interconverting conformations. AlphaFold2 is designed to predict single stable structures, so it struggles with proteins like alpha-synuclein that are inherently flexible. The low pLDDT scores indicate we cannot confidently interpret specific structural features from this prediction, but they accurately capture the disordered nature of the protein. Despite the limitations in structural prediction, experimental studies have established that the E46K mutation significantly enhances alpha-synuclein's propensity to interact with cellular membranes and form aggregates [3]. The lysine substitution at position 46 alters the protein's charge distribution and increases its clustering behavior when interacting with lipid membranes, which are thought to be critical sites where pathological aggregation begins. Research has shown that different alpha-synuclein variants display distinct aggregation behaviors in membrane environments, and E46K is particularly prone to forming oligomers and pores that can damage cellular membranes [3]. This membrane-disrupting activity may explain how the mutation causes the selective death of dopamine-producing neurons seen in Parkinson's disease. The pathogenic nature of E46K has been validated through multiple experimental systems. Drosophila fruit fly models expressing human E46K alpha-synuclein reproduce key features of Parkinson's disease, including neurodegeneration and motor deficits, demonstrating that this mutation is sufficient to cause disease across evolutionarily distant species [1]. Additionally, the mutation influences disease subtype characteristics: genetic studies have shown that familial Parkinson's cases linked to alpha-synuclein mutations cluster with specific pathological subtypes and show positive results on the alpha-synuclein seed amplification assay, a diagnostic test that detects aggregation-prone forms of the protein [2][4]. These findings confirm that E46K directly drives the core pathological process of abnormal alpha-synuclein aggregation. ## Works Cited [1] Mohamed et al. (2026). Modeling human neurodegenerative disorders in Drosophila: strategies and translational opportunities. Molecular biology reports. [PubMed](https://pubmed.ncbi.nlm.nih.gov/42118343/) [2] Negida et al. (2026). Genetic Associations of Parkinson's Disease Clinical, Pathological, and Data-Driven Subtypes. Genes. [PubMed](https://pubmed.ncbi.nlm.nih.gov/42074567/) [3] Das et al. (2026). Alpha synuclein variants significantly influence the propensity for clustering and pore formation in giant unilamellar vesicles. Biochimica et biophysica acta. Biomembranes. [PubMed](https://pubmed.ncbi.nlm.nih.gov/41990982/) [4] Venuto et al. (2025). Predicting CSF alpha-Synuclein Seed Amplification Assay Status From Demographics and Clinical Data. Neurology open access. [PubMed](https://pubmed.ncbi.nlm.nih.gov/41982814/) [5] Li et al. (2026). NMR characterization of the structure and interaction of an RNA aptamer targeting alpha-synuclein. Biochemical and biophysical research communications. [PubMed](https://pubmed.ncbi.nlm.nih.gov/42114215/) ## Similar Research **Protein quality control systems in neurodegeneration - culprits, mitigators, and solutions?** Ciechanover et al. (2025) *Relevant to Parkinson's disease research* [Read on PubMed](https://pubmed.ncbi.nlm.nih.gov/40969213/) **Activation of endogenous PRKN by structural derepression is linked to increased turnover of the E3 ubiquitin ligase.** Fiesel et al. (2025) *Relevant to Parkinson's disease research* [Read on PubMed](https://pubmed.ncbi.nlm.nih.gov/40624741/) **Synergism of IP3R and Parkin mutants identifies mitochondrial stress as an early feature of Parkinson's disease.** Dileep et al. (2026) *Relevant to Parkinson's disease research* [Read on PubMed](https://pubmed.ncbi.nlm.nih.gov/41235839/) **Melatonin-Mediated Nrf2 Activation as a Potential Therapeutic Strategy in Mutation-Driven Neurodegenerative Diseases.** Inigo-Catalina et al. (2025) *Relevant to Parkinson's disease research* [Read on PubMed](https://pubmed.ncbi.nlm.nih.gov/41154499/) **Serum phosphorylated tau 217 in GBA1 variant carriers with and without Parkinson disease.** Menozzi et al. (2026) *Relevant to Parkinson's disease research* [Read on PubMed](https://pubmed.ncbi.nlm.nih.gov/41569009/) --- ## Clinical Data ### ClinVar - **Classification:** Pathogenic - **Review Status:** criteria provided, multiple submitters - **Last Evaluated:** 2026-01-01 ### gnomAD Not found in gnomAD. --- ## Open Targets Disease Associations | Disease | Score | Data Sources | |---------|-------|--------------| | Hereditary late-onset Parkinson disease | 0.801 | genetic_association, genetic_literature | | Young adult-onset Parkinsonism | 0.786 | literature, genetic_association, genetic_literature | | Parkinson disease | 0.753 | rna_expression, genetic_literature, clinical, literature, genetic_association | | Lewy body dementia | 0.749 | literature, genetic_association, genetic_literature | | AL amyloidosis | 0.481 | literature, affected_pathway | | insomnia | 0.408 | literature, genetic_association | | REM sleep behavior disorder | 0.400 | literature, genetic_association | | parkinsonian-pyramidal syndrome | 0.371 | literature, genetic_association | | Cachexia | 0.336 | literature, genetic_association | | Anxiety | 0.333 | literature, genetic_association | *...and 2117 more associations* --- ## AI Research Brief # Research Brief: Alpha-Synuclein E46K Variant ## Pathogenic Mechanisms The alpha-synuclein E46K mutation represents a highly pathogenic familial Parkinson's disease (PD) variant that disrupts multiple critical cellular pathways. The E46K substitution occurs in the N-terminal amphipathic region crucial for membrane binding and protein-protein interactions, likely altering the protein's interaction with binding partners including SNCAIP, MAPT, and YWHAH. This mutation accelerates amyloid fibril formation, a process central to Lewy body pathology, while potentially compromising the protein's normal functions in synaptic vesicle regulation and cytoskeletal interactions (actin binding, alpha/beta-tubulin binding). Literature findings emphasize shared pathogenic mechanisms across alpha-synuclein variants, including enhanced protein aggregation, oxidative stress generation, proteostasis system dysfunction, and cell-type-specific vulnerabilities in dopaminergic neurons. The charge reversal from glutamate (negatively charged) to lysine (positively charged) at position 46 fundamentally alters the electrostatic properties of this critical region, promoting aberrant conformational changes that drive aggregation and impair normal physiological functions in adult locomotory behavior and cocaine response pathways. ## Clinical Significance E46K is a rare but highly penetrant familial PD mutation causing early-onset, rapidly progressive parkinsonism with severe motor symptoms and frequent cognitive impairment. Patients typically develop symptoms 10-20 years earlier than sporadic PD cases, with accelerated neurodegeneration patterns. The mutation's high pathogenicity classification is supported by its consistent disease causation in affected families and its dramatic effects on disease trajectory. Baseline data collection for E46K carriers is clinically critical for establishing reference points to monitor aggressive disease progression and implement early intervention strategies. The functional consequences extend beyond simple loss-of-function, as the variant actively promotes toxic gain-of-function through enhanced aggregation propensity and potential dominant-negative effects on wild-type alpha-synuclein. ## Therapeutic Landscape The therapeutic landscape for E46K focuses on targeting pathological aggregation while preserving physiological protein function. The N-terminal location of E46K positions it within a critical region for both aggregation initiation and functional membrane interactions, making it an important --- ## Agent Findings ### Literature (1) - **2026-05-14:** These papers provide crucial insights into how the E46K mutation specifically alters alpha-synuclein behavior, particularly its interactions with membrane lipids and aggregation properties. The research establishes E46K as a well-characterized early-onset Parkinson's disease mutation with distinct pathological features compared to other variants. ### Clinical (1) - **2026-05-14:** The E46K mutation in alpha-synuclein is a rare familial Parkinson's disease variant that causes early-onset, rapidly progressive parkinsonism with severe motor symptoms and often dementia. First baseline data collection for patients with this variant is clinically significant because it establishes critical reference points for disease progression monitoring, given that E46K carriers typically develop symptoms 10-20 years earlier than sporadic PD patients and show accelerated neurodegeneration. This initial data collection enables clinicians to implement early intervention strategies and provides essential baseline measurements for tracking the aggressive disease course characteristic of this highly penetrant genetic variant. ### Structural (1) - **2026-05-15:** AlphaFold structure update: Baseline check: 3 structure(s) found ### Synthesis (1) - **2026-05-15:** Synthesis of 1 findings (peptides): Synthesis JSON could not be parsed; raw response is in agent logs.... --- *Generated by [Clarity Protocol](https://clarityprotocol.io)* **Data Sources:** - Structure predictions: AlphaFold via ColabFold - Clinical variant data: ClinVar, gnomAD - Disease associations: Open Targets Platform - Research findings: AI agents (PubMed, clinical databases)