Biology subjects

Saurin, A.

Publications and source records attributed to Saurin, A..

4 recordsLinked to original sources

bioRxiv2025

C-LTMRs Regulate Thermosensation and Gate the Transition from Acute to Chronic Pain

C-low threshold mechanoreceptors (C-LTMRs) are traditionally associated with affective touch, yet emerging evidence suggests broader roles in sensory processing and pain modulation. We developed an intersectional genetic approach to selectively ablate C-LTMRs in adult mice by combining Nav1.8IRES-FLPo and THCreER drivers with a conditional DTR reporter. This approach yields robust, tissue-specific deletion of C-LTMRs without off-target effects in non-sensory tissues. C-LTMR-ablated mice exhibit altered thermotaxis behavior, including a sharpened and spatially restricted preference for warmth, while maintaining largely intact responses to touch. Remarkably, following surgical or chemotherapeutic injury, these mice display persistent mechanical and cold hypersensitivity, implicating C-LTMRs in the resolution of pain. Transcriptomic profiling of dorsal root ganglia (DRG) and dorsal horn of the spinal cord (DHSC) revealed widespread transcriptional dysregulation in pathways related to extracellular matrix remodeling, vascular function and gliogenesis in naive mice. In C-LTMR-ablated mice, paclitaxel failed to induce pro-recovery transcriptional programs and instead promoted persistent neuroinflammatory signatures. These findings establish C-LTMRs as key modulators of pain recovery, acting through tissue-specific transcriptional programs that suppress inflammation and support sensory homeostasis.

neuroscience↗

bioRxiv2024

Single cell RNA-sequencing reveals GINIP-expressing neurons as the main targets of focused ultrasound

Dorsal root ganglion (DRG) neurons have a wide range of functions, including touch, pain and itch. These neurons have emerged as promising targets for non-invasive focused ultrasound (FUS) neuromodulation. However, our knowledge of the molecular and physical mechanisms underlying FUS-evoked responses in DRG neurons is limited. Here, we investigate the neuromodulatory capabilities of FUS in cultured DRG neurons in combination with calcium imaging. We find that a 20-MHz FUS burst of 1-ms duration at an acoustic pressure of 5 MPa elicited calcium responses in 52% of DRG neurons. Single-cell RNA sequencing reveals that the majority of FUS-sensitive neurons belong to three subsets of DRG neurons; C-LTMRs, the MRGPRD-expressing C-HTMRs and A6-LTMRs. FUS excites all these neuronal subtypes by membrane deformation, suggesting a mechanism mediated by mechanosensitive ion channels. Our results identify FUS parameters that activate distinct subsets of DRG neurons and open new avenues for using FUS stimulation to modulate DRG neuron function.

neuroscience↗

bioRxiv2024

Ambivalent partnership of the Drosophila posterior class Hox protein Abdominal-B with the Extradenticle and Homothorax cofactors

Hox proteins, a sub-group of the homeodomain (HD) transcription factor family, provide positional information for axial patterning in development and evolution. Hox protein functional specificity is reached, at least in part, through Pbc (Extradenticle (Exd) in Drosophila) and Meis/Prep (Homothorax (Hth) in Drosophila) cofactor interactions. Most of our current knowledge of Hox protein specificity stems from the study of anterior and central Hox proteins, identifying the molecular and structural bases for Hox/Pbc/Meis-Prep cooperative action. Posterior Hox class proteins, Abd-B in Drosophila and Hox9-13 in vertebrates, have been comparatively less studied. They strongly diverge from anterior and central class Hox proteins, with a low degree of HD sequence conservation and the absence of a core canonical Pbc interaction motif. Here we explore how Abd-B function interface with that of Exd/Hth using several developmental contexts, studying mutual expression control, functional dependency and intrinsic protein requirements. Results identify cross regulatory interactions setting relative expression and activity levels required for proper development. They also reveal organ-specific requirement and a binary functional interplay with Exd and Hth, either synergistic or antagonistic. This highlights context specific use of Exd/Hth cofactors, and a similar context specific use of Abd-B protein intrinsic protein requirements.

developmental biology↗

bioRxiv2018

PLZF limits enhancer activity during hematopoietic progenitor aging

PLZF (promyelocytic leukemia zinc finger) is a transcription factor acting as a global regulator of hematopoietic commitment. PLZF displays an epigenetic specificity by recruiting chromatin-modifying factors but little is known about its role in remodeling chromatin of cells committed towards a given specific hematopoietic lineage. In murine myeloid progenitors, we decipher a new role for PLZF in restraining active genes and enhancers by targeting acetylated lysine 27 of Histone H3 (H3K27ac). Functional analyses reveal that active enhancers bound by PLZF are involved in biological processes related to metabolism and associated with hematopoietic aging. Comparing the epigenome of young and old myeloid progenitors, we reveal that H3K27ac variation at active enhancers is a hallmark of hematopoietic aging. Taken together, these data suggest that PLZF, associated with active enhancers, appears to restrain their activity as an epigenetic gatekeeper of hematopoietic aging.

molecular biology↗