Biology subjects

Drummond, E.

Publications and source records attributed to Drummond, E..

7 recordsLinked to original sources

bioRxiv2026

Semaphorin 3G (SEMA3G) is a highly selective marker of cerebral amyloid angiopathy

Biomarkers of cerebral amyloid angiopathy (CAA) are critically needed. We recently identified semaphorin 3G (SEMA3G) as a novel protein selectively enriched in CAA. Here, we aimed to determine if SEMA3G was a selective marker of CAA in a large cohort of human brain tissue spanning multiple neurodegenerative diseases and three brain regions, and to determine if SEMA3G directly interacts with amyloid beta (A{beta}). Multiplexed immunofluorescence showed that SEMA3G significantly accumulated only in CAA+ blood vessels in the brain in all cases. We also showed that SEMA3G preferentially associated with A{beta}40, A{beta}pS8 and A{beta}pE3, but not A{beta}42. Thioflavin T assays and transmission electron microscopy showed that SEMA3G directly interacted with A{beta} and slowed A{beta} aggregation in vitro, and that this effect was more pronounced for A{beta}40 than A{beta}42. Together our results demonstrate that SEMA3G is a highly specific marker of CAA in the brain.

neuroscience↗

bioRxiv2026

Population-scale subcellular proteomics reveals intracellular remodelling across the Alzheimer's disease-resilience spectrum

Proteome-wide analyses of human tissue have transformed our understanding of disease, but provide limited insight into protein localisation, a functionally informative dimension of the proteome. In Alzheimer's disease, amyloid-{beta} and tau exhibit aberrant localisation, yet whether spatial reorganisation extends proteome-wide has remained inaccessible to abundance-based proteomics. Here, we develop comparative subcellular proteomics applied to dorsolateral prefrontal cortex from 75 individuals spanning the Alzheimer's disease-resilience spectrum, modelling protein localisation across disease. We identify 217 disease-associated localisation shifts enriched for endolysosomal function, intracellular trafficking, and RNA processing, and resolve tau proteoforms within insoluble aggregates. Our strongest localisation candidates show only modest differences in whole-tissue abundance, highlighting disease biology inaccessible to conventional proteomics. We validate co-localisation of CSNK1A1 with pathological tau and identify an unexpected neuronal localisation pattern for SCAI, a cancer-associated protein not previously characterised in human brain, highlighting the discovery potential of subcellular proteomics in tissue.

neuroscience↗

bioRxiv2026

Seeding patient-derived tau induces tauopathy-specific aggregation and lysosomal disruption in human cells

BackgroundTau aggregation is the defining feature of tauopathies, however, the mechanisms by which distinct tau strains drive disease-specific responses remain unclear. Existing models largely rely on recombinant tau seeding or tau overexpression, which fail to capture the biochemical diversity of pathological tau. The aim of this study was to develop a robust and reproducible human cell-based model of disease-specific tau pathology and to use this model to determine how tau from unique diseases impact tau accumulation and lysosomal dysfunction. MethodsPatient-derived tau aggregates were enriched from post-mortem brain tissue obtained from sporadic Alzheimers disease (AD), Picks disease (PiD), progressive supranuclear palsy (PSP), and control cases using phosphotungstic acid precipitation. Patient-derived tau preparations were biochemically characterised by immunoblotting and mass spectrometry and normalised for tau content prior to seeding. Patient-derived tau aggregates were seeded into multiple human immortalised cell lines (SH-SY5Y, M03.13, U-87 MG, and U-118 MG cells) and iPSC-derived astrocytes. Tau seeding efficiency, aggregate morphology, and integrity of the autophagy-lysosomal pathway was assessed using quantitative imaging approaches. ResultsPatient-derived tau seeds retained disease-specific phosphorylation patterns and isoform composition and led to reproducible, dose-dependent insoluble tau accumulation in all cell lines tested. Despite equivalent tau input and similar background protein composition, PiD-derived tau had the most aggressive pathological signature, showing the highest number of tau aggregates per cell and inducing system wide disruptions in the autophagy lysosomal system including increased SQSTM1 puncta and lysosomal damage markers. Seeding with AD-derived tau led to a high number of tau aggregates per cell and more specifically depleted the lysosomal protease CTSD and uniquely co-seeded A{beta} pathology. Seeding with PSP-derived tau resulted in only a moderate number of tau aggregates per cell and uniquely caused increased lysosomal biogenesis. ConclusionsTogether, these results demonstrate that intrinsic properties of human tau strains drive disease-specific cellular responses and establish a scalable, physiologically relevant platform for dissecting tau-cell interactions and screening therapeutics across tauopathies.

cell biology↗

bioRxiv2026

Validated CRISPR/Cas9 guide RNAs targeting neurodevelopmental genes in the tunicate Ciona robusta

The development of the central nervous system (CNS) depends on tightly regulated gene expression programs that guide neural progenitor differentiation and neuronal subtype specification. The tunicate Ciona robusta provides a powerful and simplified model for dissecting the genetic control of nervous system development, with a larval CNS composed of just over 200 neurons and sensory cells. Although CRISPR/Cas9-mediated mutagenesis is now routinely used in Ciona, validated single-guide RNAs (sgRNAs) have yet to be validated for key neural genes. Here, we report the design and experimental validation of 25 novel sgRNAs targeting eight conserved genes encoding conserved proteins involved in neurodevelopment and neural function, including six transcription factors (Cdx, Foxb, Sox1/2/3, Dmbx, Engrailed, and Mnx) and two neural effector genes (Tyrosinase and Slc18a3/VAChT). Candidate sgRNAs were selected using CRISPOR and tested for mutagenesis efficiency using Illumina-based target site amplicon sequencing. All sgRNAs induced insertions or deletions at their target loci, with most genes yielding at least one sgRNA with mutagenesis efficacy exceeding 30%, with the exception of Dmbx, for which maximal efficacy reached 25%. We further compared measured mutagenesis rates with predicted Doench 16 and Doench Ruleset 3 (RS3) scores, observing a modest but improved correlation with RS3 predictions. Based on these results, we recommend considering both scoring algorithms, with RS3 potentially offering improved predictive value for Ciona.

developmental biology↗

bioRxiv2025

Targeting intracellular tau with a gene-encoded single-chain antibody promotes neuronal homeostasis and ameliorates tau pathology

The intraneuronal aggregation of tau is a key driver of pathogenesis in Alzheimer's disease and other tauopathies. The positively charged proline-rich region and microtubule-binding domain of tau are important for tubulin binding which enables axonal transport in physiological conditions. In disease, however, the positively charged repeat domains of such regions become exposed, facilitating tau-tau aggregation and other pathogenic tau-protein interactions which leads to neuronal dysfunction. Here, we generated a polyanionic peptide to electrostatically interact with tau and fused it to an inert single-chain variable fragment (scFv) antibody for improved peptide half-life and downstream intraneuronal expression. The resultant polyanionic peptibody, ACR12, was investigated in vitro and in tau transgenic mice for ability to prevent tau aggregation and associated disease phenotypes. In human neuroblastoma cells, ACR12 was stably expressed within the cytoplasm where it successfully engaged intracellular tau. DNA encoding ACR12 was then packaged into a brain-penetrant Adeno-associated virus, AAV-PHP.eB, for intravenous delivery into K3 tau transgenic mice. Such treatment facilitated long-term intraneuronal expression of ACR12 and reduced total and phosphorylated tau in the brain. ACR12 treatment in female K3 mice also restored deregulated neuronal proteins to wild-type levels. This study highlights the role of positively charged domains in tau pathogenesis and demonstrates the therapeutic utility of electrostatic tau interactors.

neuroscience↗

bioRxiv2023

Compilation of all known protein changes in the human Alzheimer's disease brain

Proteomic studies of human Alzheimers disease brain tissue have exceptional potential to identify protein changes that drive disease and to identify new drug targets. Here, we detail a combined analysis of 38 published Alzheimers disease proteomic studies, generating a comprehensive map of protein changes in human brain tissue across thirteen brain regions, three disease stages (preclinical Alzheimers disease, mild cognitive impairment, advanced Alzheimers disease), and proteins enriched in amyloid plaques, neurofibrillary tangles, and cerebral amyloid angiopathy. Our dataset is compiled into a user-friendly, searchable database called NeuroPro. Our combined analysis included 18,119 reported protein differences in human Alzheimers disease brain tissue, which mapped to 5,311 total altered proteins. Proteomic studies were remarkably consistent. 848 proteins were consistently altered in [≥]5 studies, many of which are understudied in the Alzheimers field. Comparison of protein changes in early-stage and advanced Alzheimers disease revealed significant synapse, vesicle, and lysosomal changes early in disease, but widespread mitochondrial changes only in advanced Alzheimers disease. Comparison of vulnerable and resistant brain regions suggested that protein changes in resistant regions in advanced Alzheimers disease are similar to those in vulnerable regions in early-stage Alzheimers disease, indicating a temporal progression of protein dysfunction during Alzheimers disease advancement. We conclude that NeuroPro is a powerful new resource that provides new insights into human Alzheimers disease brain protein changes and highlights novel proteins of particular interest that may mechanistically drive Alzheimers disease.

neuroscience↗

bioRxiv2020

Proteomic and Transcriptomic Analyses of the Hippocampus and Cortex in SUDEP and High-Risk SUDEP Cases

Sudden unexpected death in epilepsy (SUDEP) is the leading type of epilepsy-related death. Severely depressed brain activity in these cases may impair respiration, arousal, and protective reflexes, occurring as a prolonged postictal generalized EEG suppression (PGES) and resulting in a high-risk for SUDEP. In autopsy hippocampus and cortex, we observed no proteomic differences between SUDEP and epilepsy cases, contrasting our previously reported robust differences between epilepsy and controls. Transcriptomics in hippocampus and cortex from surgical epilepsy cases segregated by PGES identified 55 differentially expressed genes (37 protein-coding, 15 lncRNAs, three pending) in hippocampus. Overall, the SUDEP proteome and high-risk SUDEP transcriptome largely reflected other epilepsy cases in the brain regions analyzed, consistent with diverse epilepsy syndromes and comorbidities associated with SUDEP. Thus, studies with larger cohorts and different epilepsy syndromes, as well as additional anatomic regions may identify molecular mechanisms of SUDEP.

neuroscience↗