Biology subjects

Bhuiyan, S. A.

Publications and source records attributed to Bhuiyan, S. A..

7 recordsLinked to original sources

bioRxiv2026

Translational insights into canine dorsal root ganglia cell types using cross-species comparisons

Chronic pain accounts for nearly half of owner-reported canine euthanasia decisions, yet dogs remain underutilized as a large-animal model for studying pain and developing translational therapeutics. Here, we present a canine dorsal root ganglion (DRG) cell atlas generated from six donors, representing five breeds, both sexes, and three spinal segments. Our dataset comprises 3,026 neurons and 11,734 non-neuronal cells and resolves 15 neuronal subtypes that map cleanly onto A- and C-fiber classes. We further identify eight major non-neuronal subtypes, including glial, vascular, and immune populations and characterize neuronal and non-neuronal expression of physiologically relevant neuropeptides, receptors, and ion channels. We identify region-specific differences in subtype composition between lumbar and sacral DRGs, with transcriptional programs suggestive of enhanced tactile-associated signaling in lumbar DRGs and heightened nociception-associated signaling in sacral DRGs. Cross-species comparisons reveal that canine DRG subtypes are broadly conserved with human and mouse, while also exhibiting canine-specific and canine-human shared molecular features relevant for translation. Together, this atlas serves as a valuable resource for understanding canine sensory neurobiology, comparing DRG organization across mammals, and leveraging dogs as a translational model for pain research and therapeutic development.

neuroscience↗

bioRxiv2026

Multi-omic profiling of human and mouse dorsal root ganglia enables targeted gene delivery to nociceptors

Chronic pain conditions are often driven by hyperexcitability of nociceptors, the peripheral sensory neurons that detect noxious stimuli. Recent single-cell transcriptomic studies have begun to clarify the molecular identity of distinct peripheral sensory neuron subtypes, but tools that restrict transgene expression to nociceptors while sparing other dorsal root ganglion (DRG) subtypes remain limited. Here, we combined single-nucleus multi-omic profiling of human and mouse DRG with in vivo AAV enhancer screening to identify cis-regulatory elements that drive biased AAV expression in mouse DRG nociceptors and human iPSC-derived nociceptors. We then validated that an enhancer AAV designed to express Kir2.1 preferentially in nociceptors reduces DRG neuronal excitability. Leveraging these multi-omic datasets, we trained a sequence-based model to decode the cis-regulatory logic of nociceptors, enabling both the prioritization of native candidate elements and the design of synthetic enhancers with a range of nociceptor targeting properties. Together, these cross-species multi-omic resources define conserved DRG regulatory programs and provide a viral toolkit for pain research with potential translational applications for patients with refractory pain.

neuroscience↗

bioRxiv2025

A Reference Atlas of the Human Dorsal Root Ganglion

Somatosensory perception largely emerges from diverse peripheral sensory neurons whose cell bodies reside in dorsal root ganglia (DRG). Damage or dysfunction of DRG neurons is a major cause of chronic pain and sensory loss. In mice, deep single-cell transcriptomic profiling and genetically defined models have offered important clues into DRG function, but in humans, the cellular and molecular landscape of DRG neurons remains less understood. Here, we constructed a reference cell atlas of the human DRG by profiling transcriptomes of cells and nuclei from 126 donors sampled across cervical, thoracic, and lumbar DRGs. This atlas resolves 22 neuronal subtypes, including known and previously unrecognized subtypes linked to nociception, mechanosensation, thermosensation, and proprioception, as well as 10 types of non-neuronal cells. Cross-species integration, spatial transcriptomics, and microneurography enabled cell-type-specific comparisons of soma size and conduction velocity between species. Human DRG somata are larger across all cell types than their mouse counterparts, and the conduction velocities of human hair follicle innervating A-fibers are faster than in mice, suggesting a functional shift in rapid mechanical detection in humans. This integrated human DRG reference cell atlas provides a resource for exploring new molecular and physiological features of human DRG, which could help identify new strategies for treating chronic pain and other diseases of the peripheral nervous system.

neuroscience↗

bioRxiv2025

Injured SSTR2+ nociceptor axons in neuromas drive chronic spontaneous neuropathic pain

Spontaneous pain is a common but poorly understood consequence of peripheral nerve injury1-3, including injuries that lead to the formation of neuromas4,5. We developed a chronic neuroma model for measuring spontaneous pain-related behaviours in mice, which revealed that limb flicks - emerging predominantly 2 months post-injury - reflect spontaneous paroxysmal pain. Ectopic activity of injured dorsal root ganglia (DRG) sensory neurons whose axonal endings terminate within the neuroma drives this spontaneous pain. In vivo imaging showed that a subset of small-diameter DRG sensory neurons are the source of spontaneous neural signals emanating from the neuroma, and these spontaneously active neurons are distinct from the intact larger diameter sensory neurons that mediate stimulus-evoked mechanical allodynia from spared nerves. Cell-type-specific gain- and loss-of-function studies identified a genetically- and functionally-defined subtype of small-diameter C-fibre nociceptors whose injured axons in neuromas drive spontaneous limb flicks/neuropathic pain. These findings establish the neurobiological basis of spontaneous pain enabling targeted pain management strategies and define a cellular and mechanistic separation between spontaneous and evoked neuropathic pain.

neuroscience↗

bioRxiv2025

Profiling local translatomes and RNA binding proteins of somatosensory neuronsreveals specializations of individual axons

Neurons extend long axons that traverse distinct microenvironments, yet how these compartments acquire and maintain specialized molecular identities remains unclear. Here, we use spatial translatomics to define the local axonal translatomes of dorsal root ganglion (DRG) neurons that mediate somatosensation. Translating Ribosome Affinity Purification and RNA sequencing revealed thousands of mRNAs that are preferentially translated within the central axons, peripheral axons, or DRG soma, establishing compartment-specific translational programs. Many of these transcripts encode ion channels, neurotransmitter receptors, and structural proteins that confer distinct electrophysiological, synaptic, and regenerative properties to each axon. Cross-dataset integration with single-cell RNA-seq demonstrated that neuropathic injury elicits highly compartment-specific remodeling of these localized translational programs. We identify polarized RNA regulons coordinated by the RNA-binding proteins (RBPs) SFPQ and SRSF10, which preferentially bind and traffic mRNAs to the peripheral or central axon, respectively. These findings reveal a mechanistic framework in which RBP-guided RNA sorting and local translation establish and dynamically tune subcellular specialization in sensory neurons. HIGHLIGHTSO_LIDistinct mRNAs are translated in peripheral or central axons (painseq.shinyapps.io/CompartmentTRAP/). C_LIO_LIAxonal translatomes enable localized regulation of electrophysiology, neuronal plasticity, and regeneration. C_LIO_LIThe RBPs, SFPQ and SRSF10, enable mRNA sorting to peripheral and central axons respectively. C_LI

neuroscience↗

bioRxiv2024

Molecular architecture of human dermal sleeping nociceptors

Human dermal sleeping nociceptors display ongoing activity in neuropathic pain, affecting 10% of the population. Despite advances in rodents, a molecular marker for these mechano-insensitive C-fibers (CMis) in human skin remains elusive, preventing targeted therapy. In this translational Patch-seq study, we combine single-cell transcriptomics following electrophysiological characterization with single-nucleus and spatial transcriptomics from pigs and humans. We functionally identified CMis in pig sensory neurons with patch-clamp using adapted protocols from human microneurography. We identified oncostatin-M-receptor (OSMR) and somatostatin (SST) as marker genes for CMis. Following dermal injection in healthy human volunteers, oncostatin-M, the ligand of OSMR, exclusively modulates CMis. We identified the entire molecular architecture of human dermal sleeping nociceptors, providing new therapeutic targets and the basis for a mechanistic understanding of neuropathic pain. One Sentence SummaryWe identify the molecular architecture and specifically OSMR and SST as molecular markers for human dermal sleeping nociceptors, key players in the generation of neuropathic pain. Short versionIn this Patch-seq study, we identify OSMR and SST as molecular markers for human dermal sleeping nociceptors, key players in the generation of neuropathic pain.

neuroscience↗

bioRxiv2022

Cataloging the potential functional diversity of Cacna1e splice variants using long-read sequencing

Voltage gated calcium channels (VGCCs) regulate the influx of calcium ions in many cell types, but our lack of knowledge about the plethora of VGCC splice variants remains a gap in our understanding of calcium channel function. A recent advance in profiling gene splice variation is to use long-read RNA-sequencing technology. We sequenced Cacna1e transcripts from the rat thalamus using Oxford Nanopore sequencing, yielding the full structure of 2,110 Cacna1e splice variants. However, we observed that only 154 Cacna1e splice variants were likely to encode for a functional VGCC based on predicted amino acid sequences. We then computationally prioritized these 154 splice variants using expression and evolutionary conservation and found that four splice variants are candidate functionally distinct splice isoforms. Our work not only provides long-read sequencing of Cacna1e for the first time, but also the first computational evaluation of which Cacna1e splice variants are the best candidates for future follow-up. SIGNIFICANCE STATEMENTVoltage gated calcium channels (Cacna1x genes) are implicated in many neurological disorders and their encoding genes are predicted to have complex patterns of alternative splicing. Previous approaches relied on short-read RNA-seq to characterize calcium channel splice variants. Here, we use long-read nanopore sequencing to establish a set of Cacna1e transcripts in the rat thalamus and use computational methods to prioritize four transcripts as functionally distinct splice isoforms. Our work to provide the field with prioritized transcripts will not only improve our understanding of Cacna1e function but its role in disease as well.

neuroscience↗