Interrogating alpha-synuclein aggregate-associated proteomes to identify modifiers of lewy body disease. - 1. Abstract after alzheimer's disease, lewy body dementia is the most common form of dementia…

The National Institute of Neurological Disorders and Stroke, part of the Department of Health and Human Services National Institutes of Health, awarded $1.878 million to Mayo Clinic Jacksonville on September 7, 2026, under the Extramural Research Programs in the Neurosciences and Neurological Disorders program (CFDA 93.853) to interrogate alpha-synuclein aggregate-associated proteomes and identify modifiers of Lewy body disease.

The project, running through August 31, 2029, employs proximity-dependent biotin identification and in situ probe-dependent proximity profiling to capture, identify, and differentiate intracellular proteins in proximity to soluble and insoluble alpha-synuclein under physiological and pathogenic conditions. In Aim 1, the recipient will use proximity-dependent biotin identification in live human neurons and mouse brain slices and employ quantitative mass spectrometry to isolate and identify biotinylated proteins associated with alpha-synuclein in human iPSC-derived neurons and glia and in murine organotypic brain slice cultures. In Aim 2, the recipient will use in situ probe-dependent proximity profiling in human postmortem brain tissue to probe the alpha-synuclein-associated proteome across different synucleinopathies including Lewy body dementia, Parkinson's disease, and multiple system atrophy. The work advances mechanistic understanding of alpha-synuclein's role in Alzheimer disease-related dementias by revealing key cofactors in aggregation and neurodegeneration processes. Place of performance is Jacksonville, Florida.

Interrogating alpha-synuclein aggregate-associated proteomes to identify modifiers of lewy body disease. - 1. Abstract after alzheimer's disease, lewy body dementia is the most common form of dementia afflicting aging individuals. The goal of this project is to advance our mechanistic understanding of the role that alpha-synuclein plays in disease pathogenesis and progression of alzheimer disease related dementias (adrds) such as lewy body dementia (LBD) by discovering molecular interactors of alpha-synuclein and defining the alpha-synuclein aggregate-associated interactome. We hypothesize that the cellular and molecular environment contributes to αsyn-associated lewy pathology processes and that quantitative proteomics can be applied to capture the molecular microenvironment proximal to αsyn as IT forms oligomers, protofibrils, and insoluble aggregates to reveal key cofactors in aggregation and neurodegeneration processes. In this application we will employ proximity-dependent biotin identification in live human neurons and mouse brain slices (bioid) (aim 1) and in situ probe-dependent proximity profiling in fixed human patient brain tissue (proppr) (aim 2) to enable biotinylation of αsyn-associated cofactors under physiological and pathogenic conditions. Proximal biotinylated proteins will be isolated via affinity purification and identified by quantitative mass spectrometry. We propose the following coordinated aims to accomplish this goal: in aim 1 we will capture, identify, and differentiate intracellular proteins in proximity to soluble alpha-synuclein in vitro in human ipsc-derived neurons and glia and EX vivo in murine organotypic brain slice cultures, or in proximity to insoluble aggregates of alpha- synuclein induced by human-derived proteopathic seeds. In aim 2 we will use in situ probe-dependent proximity profiling in human postmortem brain to probe the αsyn-associated proteome in different synucleinopathies (DLB, PD, MSA), over time (comparing brain regions affected early versus late in disease course), and with consideration of comorbid pathologies (TAU, TDP-43, beta-amyloid) to reveal the underlying global and local proteomic landscape of synucleinopathies and shed light on the molecular heterogeneity and mechanisms underlying disease. Finally in aim 3 we will functionally investigate the pathophysiological role of select candidate proteins in human tissue, cell models, EX vivo brain slice cultures or in vivo in murine models. Successful completion of these aims will specifically identify molecular cofactors of αsyn monomers, oligomers, and aggregates and determine the processes at play during lewy pathology formation, maturation, and progression.