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Qiu, Z.

Publications and source records attributed to Qiu, Z..

At least 91 records · Page 5Linked to original sources

Inhibition of the proton-activated chloride channel PAC by PIP2

Proton-Activated Chloride (PAC) channel is a ubiquitously expressed pH-sensing ion channel that regulates endosomal acidification and macropinosome shrinkage by releasing chloride from the organelle lumens. It is also found at the cell surface, where it is activated under pathological conditions related to acidosis and contributes to acid-induced cell death. However, the pharmacology of the PAC channel is poorly understood. Here, we report that phosphatidylinositol (4,5)-bisphosphate (PIP2) potently inhibits PAC channel activity. We solved the cryo-electron microscopy structure of PAC with PIP2 at pH 4.0 and identified its binding site, which, surprisingly, locates on the extracellular side of the transmembrane domain (TMD). While the overall conformation resembles the previously resolved PAC structure in the desensitized state, the TMD undergoes remodeling upon PIP2-binding. Structural and electrophysiological analyses suggest that PIP2 inhibits the PAC channel by stabilizing the channel in a desensitized-like conformation. To our knowledge, PAC is the first chloride channel reported to be inhibited by PIP2. Our findings identify PIP2 as a new pharmacological tool for the PAC channel and lay the foundation for future drug discovery targeting this channel.

biochemistry↗

lncRNA-WAL Promotes Aggressiveness of Triple-Negative Breast Cancer via inducing β-Catenin nuclear translocation.

Because of its insensitive to existing radiotherapy, chemotherapy and targeted treatments, Triple-negative breast cancer (TNBC) remains a great challenge to overcome. More and more evidence has indicated abnormal wnt/{beta}-catenin pathway activation in TNBC but not luminal or her2+ breast cancer, and lncRNAs play a key role in a variety of cancers. Through lncRNA microarray profiling between Activated and inactivated Wnt/{beta}-catenin pathway of TNBC tissues, lnc-WAL (Wnt/{beta}-catenin associated lncRNA; WAL) was selected as the top up-regulated lncRNA in Wnt/{beta}-catenin pathway activation compared with the inactivation group. RIP-seq was analyzed between {beta}-catenin and IgG groups of, where lnc-WAL could interact with {beta}-catenin. Clinically, increased lnc-WAL in the TNBC tumor tissue was associated with shorter survival. lnc-WAL promoted the EMT, the ability of breast cancer stem cells (BCSC), proliferation, migration and invasion of TNBC cells. Mechanistically, lnc-WAL inhibited {beta}-catenin protein degradation via Axin-mediated phosphorylation at serine 45. Subsequently, {beta}-catenin was accumulated in nuclear and activated the target genes. Importantly, Wnt/{beta}-catenin pathway activation stimulated the transcription of lnc-WAL. These results pointed to a master regulatory role of lnc-WAL/Axin/{beta}-catenin in the malignant progression of TNBC. Our findings provide important clinical translational evidence that lnc-WAL maybe as potential therapeutic target against TNBC.

genetics↗

Molecular mechanism underlying desensitization of the proton-activated chloride channel PAC

Desensitization is a common property of membrane receptors, including ion channels. The newly identified proton-activated chloride (PAC) channel plays an important role in regulating the pH and size of organelles in the endocytic pathway, and is also involved in acid-induced cell death. However, how the PAC channel desensitizes is largely unknown. Here, we show by patch-clamp electrophysiological studies that PAC undergoes pH-dependent desensitization upon prolonged acid exposure. Through structure-guided and comprehensive mutagenesis, we identified several residues critical for PAC desensitization, including histidine (H) 98, glutamic acid (E) 94, and aspartic acid (D) 91 at the extracellular extension of the transmembrane helix 1 (TM1), as well as E107, D109, and E250 at the extracellular domain (ECD)-transmembrane domain (TMD) interface. Structural analysis and molecular dynamic simulations revealed extensive interactions between residues at the TM1 extension and those at the ECD-TMD interface. These interactions likely facilitate PAC desensitization by stabilizing the desensitized conformation of TM1, which undergoes a characteristic rotational movement from the resting and activated states to the desensitized state. Our studies establish a new paradigm of channel desensitization in this ubiquitously expressed ion channel and pave the way for future investigation of its relevance in cellular physiology and disease.

biophysics↗

Inhibition inputs from hippocampal CA1 to retrosplenial agranular cortex gate social behavior

Retrosplenial cortex has been implicated in processing sensory information and spatial learning, with abnormal neural activity observed in association with psychedelics and in mouse and non-human primate models of autism spectrum disorders (ASD). The direct role of the retrosplenial cortex in regulating social behaviors remains unclear. This work reveals that the neural activity of retrosplenial agranular cortex (RSA), a subregion of retrosplenial cortex, is initially activated, then quickly suppressed upon social contact. The up-down phase of RSA neurons is crucial for normal social behaviors. PV-positive GABAergic neurons in the hippocampal CA1 region were found to send inhibitory projections to RSA. Blocking these CA1-RSA inhibitory inputs significantly impaired social behavior. Notably, enhancing the CA1-RSA inhibitory input could rescue social behavior defects in an ASD mouse model. This work suggests a neural mechanism for salience processing of social behavior and identifies a potential target for ASD intervention using neural modulation approaches.

neuroscience↗

Clean-PIE: a novel strategy for efficiently constructing precise circRNA with thoroughly minimized immunogenicity to direct potent and durable protein expression

Translatable circular RNAs (circRNAs) are emerging as a crucial molecular format for transient protein expression, with high potential to be an alternative for linear mRNA to reshape the landscape of mRNA pharmaceutical industry. Canonical Anabaena permuted intron-exon (Ana PIE) format that developed by ORNA is an efficient method for RNA circularization, and the engineered circRNAs direct supreme protein expression in eukaryotic cells. However, recent studies revealed that this method may unavoidably result in a remain of immunogenicity in the circRNA products, albeit after thorough RNA purification. In the current study, we develop a novel strategy for efficient generation of circRNA, via the permuted T4Td introns mediated autocatalytically ribozymatic reaction mediated ligation of the flanking segment sequences that concealing in ORF or translation initiation sequence (normally equal to IRES). This strategy universally realizes around 90% circularization effectivity, and the circRNA products can be purified to around 90% purity by our new purification method, and presented thoroughly minimized immunogenicity, thus is termed "Clean-PIE". The purified circRNAs are found to direct potent and durable expression of various proteins in vitro and in vivo. The partly purified Fluc circRNA by HPLC-SEC was found to direct Fluc expression in muscle for no less than 20 days. The highly purified circRNA exhibits much stronger protein expression in vitro and in vivo, and presumed a longer duration. Additionally, the scale-up of RNA circularization with the RNA precursors from 1 L transcription revealed high circularization effectivity (around 90%) and a high productivity of the final circRNA products. Collectively, Clean-PIE is a novel circRNA platform that possesses high circularization effectivity, enabled high RNA purity and thoroughly minimized immunogenicity, as well as scaling-up accessibility and directing extreme durability of protein expression, thus has the potential to develop advanced RNA vaccines and therapeutics in pharmaceutical industrial scale.

molecular biology↗

Whole-brain in vivo base editing reverses autistic-like behaviors in mice

Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder associated with deficits in social communication and stereotypical behaviors. Numerous ASD-related genetic mutations have been identified and genome editing methods have been developed but successful genome editing in the whole-brain scale to alleviate autistic-like behaviors in animal models has not been achieved. Here we report the development of a new CRISPR-mediated cytidine base editor (CBE) system, which converts C{middle dot}G base pairs to T{middle dot}A. We demonstrate the effectiveness of this system by targeting an ASD-associated de novo mutation in the MEF2C gene (c.104T>C, p.L35P). We constructed a Mef2c L35P knock-in mouse and observed that Mef2c L35P heterozygous mice displayed autistic-like behaviors, including deficits in social behaviors and repetitive behaviors. We programmed the CBE to edit the C{middle dot}G base pairs of the mutated Mef2c gene (c.104T>C, p.L35P) to T{middle dot}A base pairs and delivered it via a single dose intravenous injection of blood brain barrier (BBB)-crossing AAV-PHP.eB vector into the mouse brain. This treatment restored MEF2C protein levels and reversed impairments in social interactions and repetitive behaviors in Mef2c L35P heterozygous mice. Together, this work presents an in vivo gene editing strategy in which correcting a single nucleotide mutation in the whole-brain scale could be successfully achieved, further providing a new therapeutic framework for neurodevelopmental disorders.

neuroscience↗

Developmental resilience of synaptome architecture

Neurodevelopmental disorders of genetic origin delay the acquisition of normal abilities and cause disabling phenotypes. Spontaneous attenuation and even complete amelioration of symptoms in early childhood and adolescence occur in many disorders1-10, suggesting that brain circuits possess an intrinsic capacity to repair themselves. We examined the molecular composition of almost a trillion excitatory synapses on a brain-wide scale between birth and adulthood in mice carrying a mutation in the homeobox transcription factor Pax6, a neurodevelopmental disorder model11. Pax6 haploinsufficiency had no impact on total synapse number at any age. By contrast, the postnatal expansion of synapse diversity and acquisition of normal synaptome architecture were delayed in all brain regions, interfering with network and cognitive functions. Specific excitatory synapse types and subtypes were affected in two key developmental age-windows. These phenotypes were reversed within 2-3 weeks of onset, restoring synaptome architecture to its normal developmental trajectory. Synapse subtypes with high rates of protein turnover mediated these events. These results show synaptome remodelling confers resilience to neurodevelopmental disorders.

neuroscience↗

A brain atlas of synapse protein lifetime across the mouse lifespan.

Protein turnover is required for synapse maintenance and remodelling and may impact memory duration. We quantified the lifetime of postsynaptic protein PSD95 in individual excitatory synapses across the mouse brain and lifespan, generating the Protein Lifetime Synaptome Atlas. Excitatory synapses have a wide range of protein lifetimes that may extend from a few hours to several months, with distinct spatial distributions in dendrites, neuron types and brain regions. Short protein lifetime (SPL) synapses are enriched in developing animals and in regions controlling innate behaviors, whereas long protein lifetime (LPL) synapses accumulate during development, are enriched in the cortex and CA1 where memories are stored, and are preferentially preserved in old age. The protein lifetime synaptome architecture is disrupted in an autism model, with synapse protein lifetime increased throughout the brain. These findings add a further layer to synapse diversity in the brain and enrich prevailing concepts in behavior, development, ageing and brain repair.

neuroscience↗

Ubiquitin Ligase SmDDA1b of Eggplant (Solanum melongena) Enhances Bacterial Wilt Resistance via SmNAC Degradation

Bacterial wilt (BW) is a soil-borne disease that severely impacts plant growth and productivity globally. Ubiquitination plays a crucial role in disease resistance. Our previous research indicated that NAC transcription factor SmNAC negatively regulates BW resistance in eggplant (Solanum melongena). However, whether the ubiquitin/26S proteasome system (UPS) participates in this regulation is unknown. This study used SmNAC as a bait to screen eggplant cDNA library and obtained SmDDA1b, an E3 ubiquitin ligase. Subcellular location and bimolecular fluorescence complementation assays revealed that SmDDA1b could interact with SmNAC in the nucleus. The in vivo and in vitro ubiquitination experiments indicated that SmDDA1b can degrade SmNAC through UPS. However, the discovery of negative regulation of SmDDA1b expression by SmNAC showed that there was a negative feedback loop between SmNAC and SmDDA1b in eggplant. The SmDDA1b-overexpressed lines showed a higher BW resistance associated with high expression levels of salicylic acid (SA)-related genes and SA content than the wild-type lines. However, SmDDA1b-silencing lines showed the opposite results, indicating that SmDDA1b is a positive regulatory gene for BW resistance. This study provides a candidate gene that can enhance BW resistance in eggplants. In addition, it provides insight into a mechanism that promotes plant disease resistance via the SmDDA1b-SmNAC-SA pathway.

molecular biology↗

Circuit-specific sonogenetic stimulation of the deep brain elicits distinct signaling and behaviors in freely moving mice

Sonogenetics uses heterologously-expressed proteins to sensitize neurons to ultrasound, enabling selective, non-invasive, and deep brain stimulation. However, its ability to modulate specific circuits or induce behavioral changes remains to be studied and characterized. Here, we demonstrate that sonogenetics enables efficient activation of well-defined neural circuits by transcranial low-intensity, low-frequency ultrasonic stimulation with high spatiotemporal resolution. Targeted neurons in subcortical regions were made to express a mechanosensitive ion channel (MscL-G22S). Ultrasound could trigger activity in MscL-expressing neurons in the dorsal striatum without increased activation in neighboring regions, and increase locomotion in freely-moving mice. Ultrasound stimulation of MscL-expressing neurons in the ventral tegmental area could activate the mesolimbic pathway to trigger dopamine release in the nucleus accumbens and modulate appetitive conditioning. In MscL-expressing cells, neuronal responses to ultrasound pulses were rapid, reversible and repeatable. Altogether, we show that sonogenetics can selectively manipulate targeted cells to activate defined neural pathways and affect behaviors.

neuroscience↗

De novo variants in Chinese ASD trios reveal genetic basis underlying autism without developmental delay and intellectual disabilities

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that causes a range of social communication and behavioral impairments. ASD typically manifests in young children, often with developmental delay or intellectual disabilities (DD/ID) as comorbidities. Accruing evidence indicates that ASD is highly heritable and genomewide studies on ASD cohorts have defined numerous genetic contributors. Notably, most of these studies have been performed with individuals of European and Hispanic ancestry and thus there is a paucity of genetic analyses of ASD in the East Asian population. Here, we performed whole-exome sequencing on 772 ASD trios from China, combining with a previous study of 369 Chinese ASD trios, to identify de novo variants in a total of 1141 ASD trios. We found that ASD probands without DD/ID carried less disruptive de novo variants, including protein-truncating and missense variants, than ASD with DD/ID. Surprisingly, we showed that expression of genes with de novo variants found in ASD probands without DD/ID were enriched in a specific group of neural progenitor cells, suggesting a potential mechanism underlying high-functioning autism. Importantly, some ASD risk genes from this study are not present in the current ASD gene database, suggesting that there are novel genetic contributors to ASD in East Asian populations. We validated one such novel ASD risk gene - SLC35G1 by showing that mice harboring heterozygous deletion of Slc35g1 exhibited defects in social interaction behaviors. Together, this work nominates novel ASD risk genes and indicates that ASD genetic studies in different geographic populations are essential to reveal the comprehensive genetic architecture of ASD.

neuroscience↗

Mapping brain-wide excitatory projectome of primate prefrontal cortex at submicron resolution: relevance to diffusion tractography

Resolving trajectories of axonal pathways in the primate prefrontal cortex remains crucial to gain insights into higher-order processes of cognition and emotion, which requires a comprehensive map of axonal projections linking demarcated subdivisions of prefrontal cortex and the rest of brain. Here we report a mesoscale excitatory projectome issued from the ventrolateral prefrontal cortex (vlPFC) to the entire macaque brain by using viral-based genetic axonal tracing in tandem with high-throughput serial two-photon tomography, which demonstrated prominent monosynaptic projections to other prefrontal areas, temporal, limbic and subcortical areas, relatively weak projections to parietal and insular cortices but no projections directly to the occipital lobe. In a common 3D space, we quantitatively validated an atlas of diffusion tractography-derived vlPFC connections with correlative enhanced green fluorescent protein-labelled axonal tracing, and observed generally good agreement except a major difference in the posterior projections of inferior fronto-occipital fasciculus. These findings raise an intriguing question as to how neural information passes along long-range association fiber bundles in macaque brains, and call for the caution of using diffusion tractography to map the wiring diagram of brain circuits.

neuroscience↗

Single-dose AAV-based vaccine induces a high level of neutralizing antibodies and provides long-term protection against SARS-CoV-2 in rhesus macaques

Coronavirus disease 2019 (COVID-19), which is triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, continues to threaten global public health. Developing a vaccine that only requires single immunization but provides long-term protection for the prevention and control of COVID-19 is important. Here, we developed an adeno-associated virus (AAV)-based vaccine expressing a stable receptor-binding domain (SRBD) protein. The vaccine requires only a single shot but provides effective neutralizing antibodies (NAbs) over 598 days in rhesus macaques (Macaca mulatta). Importantly, our results showed that the NAbs were kept in high level and long lasting against authentic wild-type SARS-CoV-2, Beta, Delta and Omicron variants using plaque reduction neutralization test. Of note, although we detected pre-existing AAV2/9 antibodies before immunization, the vaccine still induced high and effective NAbs against COVID-19 in rhesus macaques. AAV-SRBD immune serum also efficiently inhibited the binding of ACE2 with RBD in the SARS-CoV-2 B.1.1.7 (Alpha), B.1.351 (Beta), P.1/P.2 (Gamma), B.1.617.2 (Delta), B.1.617.1/3(Kappa), and C.37 (Lambda) variants. Thus, these data suggest that the vaccine has great potential to prevent the spread of SARS-CoV-2.

immunology↗

Precursor abundance influences divergent antigen specific CD8+ T cell responses after Yersinia pseudotuberculosis foodborne infection

Primary infection of C57BL/6 mice with the bacterial pathogen Yersinia pseudotuberculosis elicits an unusually large H-2Kb-restricted CD8+ T cell response to the endogenous and protective bacterial epitope YopE69-77. To better understand the basis for this large response, the model OVA257-264 epitope was inserted into YopE in Y. pseudotuberculosis and antigen specific CD8+ T cells in mice were characterized after foodborne infection with the resulting strain. The epitope YopE69-77 elicited significantly larger CD8+ T cell populations in the small intestine, mesenteric lymph nodes (MLNs), spleen and liver between 7- and 30-days post infection, despite residing in the same protein and having a similar affinity for H-2Kb as OVA257-264. YopE-specific CD8+ T cell precursors were ~4.6 times as abundant as OVA-specific precursors in the MLNs, spleen and other lymph nodes of naive mice, explaining the dominance of YopE69-77 over OVA257-264 at early infection times. However, other factors contributed to this dominance as the ratio of YopE-specific to OVA-specific CD8+ T cells increased between 7- and 30-days post infection. We also compared the YopE-specific and OVA-specific CD8+ T cells generated during infection for effector and memory phenotypes. Significantly higher percentages of YopE-specific cells were characterized as short short-lived effectors while higher percentages of OVA-specific cells were memory precursor effectors at day 30 post infection in spleen and liver. Our results suggest that a large precursor number contributes to the dominance and effector and memory functions of CD8+ T cells generated to the protective YopE69-77 epitope during Y. pseudotuberculosis infection of C57BL/6 mice.

immunology↗

Recovery of high-qualitied Genomes from a deep-inland Salt Lake Using BASALT

Metagenomic binning enables the in-depth characterization of microorganisms. To improve the resolution and efficiency of metagenomic binning, BASALT (Binning Across a Series of AssembLies Toolkit), a novel binning toolkit was present in this study, which recovers, compares and optimizes metagenomic assembled genomes (MAGs) across a series of assemblies from short-read, long-read or hybrid strategies. BASALT incorporates self-designed algorithms which automates the separation of redundant bins, elongate and refine best bins and improve contiguity. Evaluation using mock communities revealed that BASALT auto-binning obtained up to 51% more number of MAGs with up to 10 times better MAG quality from microbial community at low (132 genomes) and medium (596 genomes) complexity, compared to other binners such as DASTool, VAMB and metaWRAP. Using BASALT, a case-study analysis of a Salt Lake sediment microbial community from northwest arid region of China was performed, resulting in 426 non-redundant MAGs, including 352 and 69 bacterial and archaeal MAGs which could not be assigned to any known species from GTDB (ANI < 95%), respectively. In addition, two Lokiarchaeotal MAGs that belong to superphylum Asgardarchaeota were observed from Salt Lake sediment samples. This is the first time that candidate species from phylum Lokiarchaeota was found in the arid and deep-inland environment, filling the current knowledge gap of earth microbiome. Overall, BASALT is proven to be a robust toolkit for metagenomic binning, and more importantly, expand the Tree of Life.

bioinformatics↗

SENP1 in the retrosplenial agranular cortex regulates core autistic-like symptoms in mice

Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder, in which core symptoms are defects of social interaction and evidently repetitive behaviors. Although around 50-70 % of ASD patients have comorbidity of intellectual disabilities (ID) or developmental delay (DD), there are some ASD patients who exhibit only core symptoms but without ID/DD, raising the question whether there are genetic components and neural circuits specific for core symptoms of ASD. Here, by focusing on ASD patients who do not show compound ID or DD, we identified a de novo heterozygous gene-truncating mutation of the Sentrin-specific peptidase1 (SENP1) gene, coding the small ubiquitin-like modifiers (SUMO) deconjugating enzyme, as a potentially new candidate gene for ASD. We found that Senp1 haploinsufficient mice exhibited core symptoms of autism such as deficits in social interaction and repetitive behaviors, but normal learning and memory ability. Moreover, we found that the inhibitory and excitatory synaptic functions were severely affected in the retrosplenial agranular (RSA) cortex of Senp1 haploinsufficient mice. Lack of Senp1 led to over SUMOylation and degradation of fragile X mental retardation protein (FMRP) proteins, which is coded by the FMR1 gene, also implicated in syndromic ASD. Importantly, re-introducing SENP1 or FMRP specifically in RSA fully rescued the defects of synaptic functions and core autistic-like symptoms of Senp1 haploinsufficient mice. Together, these results demonstrated that disruption of the SENP1-FMRP regulatory axis in the RSA may cause core autistic symptoms, which provide a candidate brain region of ASD for potential therapeutic intervene by neural modulation approaches.

neuroscience↗

Enhanced ultrasound neuromodulation in vitro using nanobubble actuators

Ultrasound neuromodulation is a promising new method to manipulate brain activity noninvasively. Here, we detail a neurostimulation scheme using gas-filled nanostructures, gas vesicles (GVs), as actuators for improving the efficacy and precision of ultrasound stimuli. Sonicated primary neurons displayed dose-dependent, repeatable Ca2+ responses, closely synced to stimuli, and increased nuclear expression of the activation marker c-Fos only in the presence of GVs but not without. We identified mechanosensitive ion channels as important mediators of this effect, and neurons heterologously expressing the mechanosensitive MscL-G22S channel showed greater activation at lower acoustic pressure. This treatment scheme was also found not to induce significant cytotoxicity, apoptosis or membrane poration in treated cells. Altogether, we demonstrate a simple and effective method to achieve enhanced and more selective ultrasound neurostimulation. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

neuroscience↗

Co-editing PINK1 and DJ-1 genes via AAV-delivered CRISPR/Cas9 system in adult monkey brains elicits classic Parkinsonian phenotypes

Whether direct manipulation of Parkinsons disease (PD) risk genes in monkey brain can elicit Parkinsonian phenotypes remains an unsolved issue. Here, we employed an adeno-associated virus (AAV)-delivered CRISPR/Cas9 system to directly co-edit PINK1 and DJ-1 genes in the substantia nigra (SN) region of four adult monkey brains. After the operation, two of the monkeys exhibited all classic PD symptoms, including bradykinesia, tremor, and postural instability, accompanied by severe nigral dopaminergic neuron loss (over 60%) and -synuclein pathology. The aged monkeys were more vulnerable to gene editing by showing faster PD progression, higher final total PD scores, and severer pathologic changes compared with their younger counterparts, suggesting both the genetic and aging factors played important roles in PD development. This gene editing system can be used to develop a large quantity of genetically edited PD monkeys over a short period, thus providing a practical transgenic monkey model for future PD studies.

neuroscience↗