Biology subjects

Rosario, J.

Publications and source records attributed to Rosario, J..

3 recordsLinked to original sources

bioRxiv2025

Brain-derived extracellular vesicle microRNAs in Lewy body and Alzheimer's disease

INTRODUCTIONRobust plasma-based biomarkers to distinguish Lewy body disease (LBD) and Alzheimers disease (AD) are currently lacking. We applied track-etch magnetic nanopore (TENPO) sorting for enrichment of brain-derived extracellular vesicle (EV) signatures as potential biomarkers to address this gap. METHODSWe analyzed plasma from 137 autopsy-confirmed patients [30 LBD, 31 AD, 30 AD/LBD, 19 AD with amygdala Lewy bodies (AD/ALB), and 27 controls], sequencing miRNAs from TENPO-isolated GluR2-positive (neuron-enriched) and GLAST-positive (astrocyte-enriched) EVs, and measuring plasma proteins (A{beta}40, A{beta}42, tau, p-Tau181, p-Tau231) via SIMOA. RESULTSWe identified 16 GluR2+, 8 GLAST+, and 4 protein biomarkers with differential expression (false discovery rate-corrected P value < .1) between LBD and AD. A multimodal 15-feature panel classified LBD versus AD with 10-fold cross-validated accuracy = 0.95 and area under the curve (AUC) = 0.96. DISCUSSIONBrain-derived EVs offer accurate and accessible miRNA biomarkers for the differential diagnosis of LBD and AD.

bioengineering↗

bioRxiv2024

Characterizing the Spatial Distribution of Dendritic RNA at Single Molecule Resolution

Neurons possess highly polarized morphology that require intricate molecular organization, partly facilitated by RNA localization. By localizing specific mRNA, neurons can modulate synaptic features through local translation and subsequent modification of protein concentrations in response to stimuli. The resulting activity-dependent modifications are essential for synaptic plasticity, and consequently, fundamental for learning and memory. Consequently, high-resolution characterization of the spatial distribution of dendritic transcripts and the spatial relationship across transcripts is critical for understanding the pathways and mechanisms underlying synaptic plasticity. In this study, we characterize the spatial distribution of six previously uncharacterized genes (Adap2, Colec12, Dtx3L, Kif5c, Nsmf, Pde2a) within the dendrites at a sub-micrometer scale, using single-molecule fluorescence in situ hybridization (smFISH). We found that spatial distributions of dendritically localized mRNA depended on both dendrite morphology and gene identity that cannot be recreated by diffusion alone, suggesting involvement of active mechanisms. Furthermore, our analysis reveals that dendritically localized mRNAs are likely co-transported and organized into clusters at larger spatial scales, indicating a more complex organization of mRNA within dendrites.

neuroscience↗

bioRxiv2019

Single Cell Spatial Chromatin Analysis of Fixed Immunocytochemically Identified Neuronal Cells

Assays examining the open-chromatin landscape in single cells require isolation of the nucleus, resulting in the loss of spatial/microenvironment information. Here we describe CHEX-seq (CHromatin EXposed) for identifying single-stranded open-chromatin DNA regions in paraformaldehyde-fixed single cells. CHEX-seq uses light-activated DNA probes that binds to single-stranded DNA in open chromatin. In situ laser activation of the annealed probes 3-Lightning Terminator in selected cells permits the probe to act as a primer for in situ enzymatic copying of single-stranded DNA that is then sequenced. CHEX-seq is benchmarked with human K562 cells and its utility is demonstrated in dispersed primary mouse and human brain cells, and immunostained cells in mouse brain sections. Further, CHEX-seq queries the openness of mitochondrial DNA in single cells. Evaluation of an individual cells chromatin landscape in its tissue context enables \"spatial chromatin analysis\".\n\nOne Sentence SummaryA new method, CHEX-seq (CHromatin eXposed), identifies the open-chromatin landscape in single fixed cells thereby allowing spatial chromatin analysis of selected cells in complex cellular environments.

neuroscience↗