# Single molecule protein sequencing of alpha-synuclein species for Parkinson's disease diagnostics

> **NIH NIH R43** · ERISYON INC · 2020 · $247,876

## Abstract

ABSTRACT Parkinson’s disease (PD) is a neurodegenerative disorder that is typically
diagnosed when 60% of a brain region’s dopaminergic neurons have already degenerated. A
strong contender for the elusive molecular biomarker is a neuronal protein - α-synuclein and its
post-translationally modified phosphorylated isoform (pSer-129). Along with other C-terminal
modifications, this modification has been found as the insoluble aggregated and fibrillar form in
the brain tissue of deceased Parkinson’s patients. The progression and disease severity has
been correlated to its relative levels in patient’s cerebrospinal fluids (CSF) as well.
 However, current technologies, such as immuno-assays and mass-spectrometry lack the
necessary sensitivity and capability to accurately quantify both the phosphorylated and
unmodified form of the protein simultaneously and in clinically limited samples, such as the
cerebrospinal fluid. This technological limitation has hampered the development of a robust
clinical assay and validation of these implicated neuronal biomarkers.
 Fluorosequencing, a new single molecule protein sequencing technology, is a massively
parallelized platform for identifying and quantifying individual proteins in a complex mixture. The
important and distinguishing feature of the single molecule platform is its inherent ability to
absolutely quantify and discriminate the different species of peptides, including the species
differing in the positions and the occupancy of phosphorylated residues.
 Through the grant phase I and II, we propose to utilize this platform technology to develop a
clinical assay for measuring the abundances of the different species of α-synuclein from
extremely limited biological samples and correlating the measurements with patient outcomes.
In phase I, we will spike-in modified and unmodified alpha-synuclein species at different
proportions into CSF, establishing assay reproducibility and replicability (aim 1) and obtain limits
of detection and discrimination between the different α-synuclein phosphorylated species (aim
2). Completing these objectives will establish an optimized work-flow and the determination of
the sample requirements necessary for measuring the levels in patient samples. Successful
completion of the two phases would result in a commercialization path towards a laboratory
developed test or diagnostic assay.

## Key facts

- **NIH application ID:** 10082331
- **Project number:** 1R43NS119141-01
- **Recipient organization:** ERISYON INC
- **Principal Investigator:** Tal Somekh
- **Activity code:** R43 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $247,876
- **Award type:** 1
- **Project period:** 2020-09-01 → 2022-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10082331

## Citation

> US National Institutes of Health, RePORTER application 10082331, Single molecule protein sequencing of alpha-synuclein species for Parkinson's disease diagnostics (1R43NS119141-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10082331. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*