Biology subjects

Zhou, S.-H.

Publications and source records attributed to Zhou, S.-H..

7 recordsLinked to original sources

bioRxiv2025

Structural Basis of Asymmetric Class C GPCR activation and distinct Gq coupling induced by force stimulation

Mechanosensation is essential for diverse physiological processes. While many G protein-coupled receptors (GPCRs) are known to be mechanosensitive, the underlying mechanism remains largely unknown. Here, we reveal that mechanical force induces Gq activation of mGlu2, a balance modulator residing in kinocilia, but not other 7 mGlu members. Force activates mGlu2 through a conserved N-terminal force transduction motif (FTM) via a unique cis mechanism. We engineered a potent FTM-derived peptide agonist that recapitulates force-induced activation and resolved cryo-EM structures of apo-mGlu2, FTM-mGlu2, LFTM-{Psi}EK-mGlu2 and LFTM-{Psi}EK-mGlu2-Gq. The structures reveal that an atypical FTM binding to a previously uncharacterized pocket induces asymmetric 7TM domain rearrangement, enabling Gq coupling via an ICL1-TM3/6/7 interface, fundamentally distinct from the glutamate-induced Gi coupling mode of mGlu2. Compared with Gi-coupled mGlu2, the 5 helix of Gq rotated by 180{degrees}, penetrating deeper (8 [A]) into a hydrophobic pocket. Disruption of the M7947.32-F7806.57-F7766.53 hydrophobic triad core and a conformational propagation path predominantly comprising TM6-7 residues are identified as key elements mediating force induced mGlu2 activation. Further In vivo rescue experiments support that mGlu2s mechanosensitivity is dependent on FTM and is required for vestibular function. This work establishes a paradigm for class C GPCR mechanotransduction, revealing unprecedented structural mechanisms underlying force-induced Gq coupling and offering a chemical toolset to modulate mechanical signaling of GPCR.

cell biology↗

bioRxiv2025

A Mechanosensitive GPCR at vestibular kinocilium is required for normal balance

Intracellular calcium increase and neurotransmitter release in vestibular hair cells (VHCs) play central roles in equilibrioception, which is one of the basic senses essential for daily life activities and movement in mammals. Independent of mechano-electrical transduction (MET), whether Gq protein-coupled receptor (GqPCR) signaling participate in the regulation of intracellular calcium dynamics and induce neuronal transmitter release in hair cells remains unknown. We screened mechanosensitive GqPCRs in VHCs and found that a Class C GPCR, metabotropic glutamate receptor 2 (mGlu2), is expressed in kinocilia and is essential for normal balance. Notably, the dispensable role of mGlu2 in normal hearing is consistent with absent of mature kinocilia in cochlea hair cells. Different from the conventional mGlu2-Gi signaling, the sensing of mechanical signals by mGlu2 activates the Gq-PLCD4 pathway, increases intracellular calcium concentration and promotes neurotransmitter release in VHCs. Hair cell-specific deficiency of either Grm2 or Gnaq, or knockdown of Plcd4 expression, but not deficiency of another GqPCR Gpr68, causes significant balance deficits. Reintroduction of mGlu2 into the VHCs of Pou4f3-CreER+/- Grm2fl/fl mice restore vestibular functions. Our study reveals a previously uncharacterized role of GPCR signaling in equilibrioception and provides important insight into kinocilia signaling in VHCs, which are absent in mature cochlear hair cells.

cell biology↗

bioRxiv2025

The role of human intraparietal sulcus in evidence accumulation revealed by EEG and model-informed fMRI

Sequential sampling models propose that the repeated sampling of sensory information is a fundamental component of perceptual decision-making. Electroencephalographic investigations in humans have demonstrated motor-independent representations of evidence accumulation, but such observations have seldom been made in neuroimaging studies exploring the neuroanatomical origins of evidence accumulation. Here, we aimed to reveal the neuroanatomical locus of sensory evidence accumulation in the human brain by regressing an electrophysiological marker of evidence accumulation (centroparietal positivity, CPP) against changes in blood oxygen level-dependent (BOLD) signal during perceptual decision-making. Our cross-modal imaging approach revealed a cluster within left intraparietal sulcus (IPS), located within putative lateral intraparietal area (region hIP3), for which BOLD signals scaled in relation to the slope of the CPP. Furthermore, the drift rate parameter of a drift diffusion model parametrically modulated BOLD activity within an overlapping region of left IPS. In contrast, parametric modulation by reaction time revealed a distributed fronto-parietal network, demonstrating the utility of our approach for isolating a discrete neuroanatomical locus of evidence accumulation. Together, our findings provide strong support for intraparietal sulcus involvement in the accumulation of sensory evidence during human perceptual decision-making.

neuroscience↗

bioRxiv2023

Neurophysiological mechanisms underlying post-stroke deficits in contralesional perceptual processing

Slowed responding to sensory inputs presented in contralesional space is pervasive following unilateral cerebral stroke, but the causal neurophysiological pathway by which this occurs remains unclear. To this end, here we leverage a perceptual decision-making framework to disambiguate information processing stages between sensation and action in 30 unilateral stroke patients (18 right hemisphere, 12 left hemisphere) and 27 neurologically healthy adults. By recording neural activity using electroencephalography (EEG) during task performance, we show that the relationship between strokes in either hemisphere and slowed contralesional response times is sequentially mediated by weaker target selection signals in the contralateral hemisphere (the N2c ERP), and subsequently delayed evidence accumulation signals (the centroparietal positivity). Notably, asymmetries in CPP and response times across hemispheres are associated with everyday functioning. Together, these data suggest a plausible neurophysiological pathway by which post-stroke contralesional slowing arises and highlight the utility of neurophysiological assessments for tracking clinically relevant behaviour.

neuroscience↗

bioRxiv2023

Neurophysiology of perceptual decision-making and its alterations in attention deficit hyperactivity disorder (ADHD)

Despite the prevalence of ADHD, efforts to develop a detailed understanding of the neuropsychology of this neurodevelopmental condition are complicated by the diversity of interindividual presentations and the inability of current clinical tests to distinguish between its sensory, attentional, arousal or motoric contributions. Identifying objective methods that can decompose the clinical heterogeneity of ADHD is a long-held goal that is hoped to advance our understanding of etiological processes and potentially aid the development of personalized treatment approaches. Here, we examine key neuropsychological components of ADHD within an electrophysiological (EEG) perceptual decision-making paradigm that is capable of isolating distinct neural signals of several key information processing stages necessary for sensory-guided actions from attentional selection to motor responses. We show that compared to typically developing children, children with ADHD displayed slower and less accurate performance, which was driven by the atypical dynamics of discrete electrophysiological signatures of attentional selection, the accumulation of sensory evidence, and strategic adjustments reflecting urgency of response. These findings offer an integrated account of decision-making in ADHD and establish discrete neural signals that can be used to understand the wide range of neuropsychological performance variations in individuals with ADHD. Significance StatementThe efficacy of diagnostic and therapeutic pathways in ADHD is limited by our incomplete understanding of its neurological basis. One promising avenue of research is the search for basic neural mechanisms that may contribute to the variety of cognitive challenges associated with ADHD. We developed a mechanistic account of differences in a fundamental cognitive process by integrating across neurocognitive, neurophysiological (i.e., EEG), and computational levels of analysis. We detected distinct neural changes in ADHD that explained altered performance (e.g., slowed and less accurate responses). These included changes in neural patterns of attentional selection, sensory information processing, and response preparation. These findings enhance our understanding of the neurophysiological profile of ADHD and may offer potential targets for more effective, personalized interventions.

neuroscience↗

bioRxiv2023

Force-sensing LPHN2 is indispensable for normal hearing and mediates MET in cochleae through Gs and CNGA3 coupling

The conversion of force sensation into electrical signals via mechanoelectrical transduction (MET) is considered the key step in auditory perception. Here, we found that G protein-coupled receptor (GPCR) LPHN2/ADGRL2 was expressed at the tips of stereocilia in cochlear hair cells and was associated with MET channel components. Hair cell-specific LPHN2 deficiency caused hearing loss and impaired MET responses. A specific inhibitor of LPHN2, developed by in silico screening and pharmacological characterization, reversibly blocked the MET response. Mechanistically, administration of force to LPHN2 activated TMC1 through direct interaction and caused conformational changes in TMC1 in vitro. Furthermore, the sensing of force by LPHN2 stimulated Ca2+ responses and neurotransmitter release in hair cells. Finally, hearing loss in LPHN2-deficient mice was reversed by the re-expression of LPHN2-GAIN in cochlear hair cells. The important roles of LPHN2 in auditory perception and a TMC-coupled force sensor indicated that GPCRs could be candidate auditory receptors.

physiology↗

bioRxiv2020

shRNA Glut-1 inhibits cell viability, apoptosis and migration of laryngeal carcinoma HEp-2 cells through regulating Beclin-1-mediated autophagy

ObjectiveGlut-1 is a key regulator in the process of glucose uptake. Previous studies have shown that Glut-1 affects autophagy. However, it is unclear whether there is a correlation between Glut-1 and autophagy in the progression of laryngeal carcinoma. This study was performed to investigate the role of Glut-1 in the development of laryngeal carcinoma. MethodsA stable HEp-2 cell model was constructed by Glut-1 and Beclin-1 shRNA lentiviral infection. The autophagosome was measured by transmission electron microscopy. Protein levels of LC3, ATG5, CyclinD1, Bcl-2, Caspase-3, and c-Myc were determined by Western blotting. CCK8 assay and Transwell assays were used to determine cell viability and migration rate of HEp-2 cells, respectively. Flow cytometry was performed to analyze the rate of apoptosis. Immunofluorescence was performed to determine the expression distribution of LC3. ResultsGlut-1 knockdown significantly promoted autophagosome formation by upregulating the ratio of LC3-II/LC3-I as well as the role of rapamycin (RAP) and Beclin-1 overexpression on autophagy flux in HEp-2 cells. Glut-1 inhibition also reduced the viability of HEp-2 cells followed by the decreases in expression of cyclinD1 and c-Myc. In addition, Glut-1 depletion increased the number of apoptotic HEp-2 cells accompanied by activation of caspase-3 and downregulation of Bcl-2. Glut-1 knockdown also reduced the migration rate of HEp-2 cells by promoting the expression of N-cadherin and inhibiting the expression of E-cadherin. Beclin-1 consumption significantly reversed Gult-1 knockdown-mediated autophagy activation, resulting in promotion of both proliferation and migration and inhibition of apoptosis. ConclusionsGlut-1 knockdown-induced autophagy inhibits the proliferation and migration of HEp-2 cells, and promotes apoptosis of HEp-2 cells partly by regulating autophagy.

cancer biology↗