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zhou, s.

Publications and source records attributed to zhou, s..

5 recordsLinked to original sources

A novel and simple maneuver greatly improves rat liver transplantation

BackgroundOrthotopic rat liver transplantation (OLT) is preferentially used to study transplant immunology; it remains challenging due to higher complications associated with 26-minute anhepatic time ceiling, here we safely extended the anhepatic time to improve success of OLT. MethodsInitially we performed OLT including whole graft OLT from inbred Sprague Dawley (SD) rat to SD (whole graft group, control group, n=21) and 30 minute anhepatic time (AHT) group (AHT group, n=11) to master this procedure. For generalization of this maneuver, partial OLT was performed from 50% Lewis allograft to Brown Norway (BN) rat to induce tolerance (half graft group, n=28), Cyclosporine A was injected once daily for 10 days in this group. ResultsFor whole graft group, 30-day survival rate was 85.5% (18/21), the reasons of death were gas embolism due to the missed suturing in 2 cases, blood loss in 1 case. For AHT group, 30-day survival rate was 72.7% (8/11), one recipient died from respiratory failure intra-operatively; two deaths were biliary leakage in 14 days. There were no differences in survival between whole graft group and AHT group (p=0.368). For tolerance group, 30-day survival rate was 82.0% (11/61), and the causes of death were diverse and recorded. ConclusionThe anhepatic time can be extended to 30 minutes simply through the change of clamping the diaphragm, which facilitates LT and improves its success good for the basic research.

systems biology↗

Force sensing GPR133 is essential for normal balance and modulates vestibular hair cell membrane excitability via Gi signaling and CNGA3 coupling

The maintenance of normal balance sensing is a fundamental prerequisite for virtually every activity of daily life. As one set most important balance information collectors, vestibular hair cells convert mechanical stimuli from head movement into electrical signals through a mechanoelectrical transduction (MET) process. The molecular mechanism underlying equilibrioception and MET in vestibular hair cells is not well understood but is generally believed to be mediated by ion channels. However, whether these procedures are also mediated by other receptors, such as GPCRs, which are known to govern light, odorant and taste sensing, is not known. Here, by screening the expression of force-sensitive adhesion GPCRs in vestibular hair cells and phenotype profiling in animal models, we identified that a seven-transmembrane receptor, GPR133, was able to sense force in utricle hair cells and was required for maintenance of normal equilibrioception. Notably, GPR133 converted mechanical stimuli into changes in intracellular cAMP levels through Gi engagement and then modulated plasma membrane excitability and mediated MET by coupling to CNGA3 activity changes in approximately 30% of GPR133-expressing utricle hair cells. GPR133-mediated MET and its coupling with CNGA3 were recapitulated by an in vitro reconstitution system. Further chemical labeling, mass spectrometry and cryo-EM analysis provided potential structural information on force-induced GPR133 activation and Gi3 engagement. Collectively, our findings reveal the essential role of GPR133 in the maintenance of normal equilibrioception and suggest that GPCR family members can participate in the MET process in utricle hair cells through modulation of intracellular second messenger levels and ion channel coupling.

physiology↗

Force sensation by a Gs-coupled adhesion GPCR mediates equilibrioception by increasing vestibular hair cell membrane excitability and CNGA3 coupling

AbstractEquilibrioception is essential for the perception and navigation of mammals in the three-dimensional world. A rapid mechanoelectrical transduction (MET) response in vestibular hair cells plays a critical role in positional and motional perception. Here, we identified that the G protein-coupled receptor LPHN2/ADGRL2, which is expressed in the apical membrane of utricular hair cells, is required for maintenance of normal balance. Hair cell-specific Lphn2 deficiency in mice impaired both balance behaviors and MET responses. Functional analyses using Pou4f3-CreER+/-; Lphn2fl/fl mice and LPHN2-specific inhibitors revealed that LPHN2 regulated the tip link-independent MET current at the apical surface of the utricular hair cell by converting force stimuli into transmembrane channel-like protein 1 (TMC1) activity. Force sensation by LPHN2 also induced glutamate release and calcium signaling in utricular hair cells. Reintroduction of LPHN2 into the hair cells of Lphn2-deficient mice restored the vestibular functions and MET responses. Our data suggest an indispensable role for a mechanosensitive GPCR in equilibrioception.

physiology↗

Spatiotemporal dynamics of molecular expression pattern and intercellular interactions in glial scar responding to spinal cord injury

Adult regeneration in spinal cord is poor in mammalian but remarkable in the neonatal mammals and some vertebrates, including fish and salamanders. Increasing evidences basis of this interspecies and ontogeny highlighted the pivotal roles of neuron extrinsic factors-the glial scar, which exert confusing inhibiting or promoting regeneration function, but the spatiotemporal ordering of cellular and molecular events that drive repair processes in scar formation remains poorly understood. Here, we firstly constructed tissue-wide gene expression measurements of mouse spinal cords over the course of scar formation using the spatial transcriptomics (ST) technology in Spinal cord injury (SCI) repair. We analyzed the transcriptomes of nearly 15449 spots from 32 samples and distinguished normal and damage response regions. Compared to histological changes, spatial mapping of differentiation transitions in spinal cord injury site delineated the possible trajectory between subpopulations of fibroblast, glia and immune cell more comprehensively and defined the extent of scar boundary and core more accurately. Locally, we identified gene expression gradients from leading edge to the core of scar areas that allow for re-understanding of the scar microenvironment and found some regulators in special cell types, such as Thbs1 and Col1a2 in macrophage, CD36 and Postn in fibroblast, Plxnb2 and Nxpe3 in microglia, Clu in astrocyte and CD74 in oligodendrocyte. Last, we profiled the bidirectional ligand-receptor interactions at the neighbor cluster boundary, contributing to maintain scar architecture during gliosis and fibrosis, and found GPR37L1_PSAP and GPR37_PSAP were top 2 enriched gene-pairs between microglia and fibroblast or microglia and astrocyte. Together, the establishment of these profiles firstly uncovered scar spatial heterogeneity and lineage trajectory, provide an unbiased view of scar and served as a valuable resource for CNS injury treatment. HighlightsO_LISpatial illustration of gene expression pattern after T10 right lateral hemisection. C_LIO_LISpatial atlas of scar formation by 21 cell types around damaged area. C_LIO_LIThe origin, trajectory reconstruction and functional diversity of cell types in different stages of scar formation. C_LIO_LINovel insights for glial scar boundary and potential benefits for recovery intervention after SCI. C_LI

neuroscience↗

The COMPASS-like complex modulates fungal development and pathogenesis by regulating H3K4me3-mediated targeted gene expression in Magnaporthe oryzae

Histone H3K4 methylation is catalysed by the multi-protein complex known as the Set1/COMPASS or MLL/COMPASS-like complex, an element that is highly evolutionarily conserved from yeast to humans. However, the components and mechanisms by which the COMPASS-like complex targets the H3K4 methylation of plant pathogenic genes in fungi remain elusive. Here we present a comprehensive analysis combining biochemical, molecular, and genome-wide approaches to characterize the roles of the COMPASS-like family in Magnaporthe oryzae, a model plant fungal pathogen. We purified and identified six conserved subunits of COMPASS from the rice blast fungus M. oryzae, i.e., MoBre2 (Cps60/ASH2L), MoSpp1 (Cps40/Cfp1), MoSwd2 (Cps35), MoSdc1 (Cps25/DPY30), MoSet1 (MLL/ALL) and MoRbBP5 (Cps50), using an affinity tag on MoBre2. We determined the SPRY domain of MoBre2 can recognize directly with DPY30 domain of MoSdc1 in vitro. Furthermore, we found that deletion of the genes encoding COMPASS subunits of MoBre2, MoSpp1 and MoSwd2 caused similar defects regarding invasive hyphal development and pathogenicity. Genome-wide profiling of H3K4me3 revealed that the it has remarkable co-occupancy at the TSS regions of target genes. Significantly, these target genes are often involved in spore germination and pathogenesis. Decreased gene expression caused by the deletion of MoBre2, MoSwd2 or MoSpp1 gene was highly correlated with decrease in H3K4me3. Taken together, these results suggest that MoBre2, MoSpp1, and MoSwd2 function as a whole COMPASS complex, contributing to fungal development and pathogenesis by regulating H3K4me3-targeted genes in M. oryzae.

microbiology↗