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Yang, Z.

Publications and source records attributed to Yang, Z..

At least 505 records · Page 28Linked to original sources

De novo macrocyclic peptides for inhibiting, stabilising and probing the function of the Retromer endosomal trafficking complex

The Retromer complex (Vps35-Vps26-Vps29) is essential for endosomal membrane trafficking and signalling. Mutations in Retromer cause late-onset Parkinsons disease, while viral and bacterial pathogens can hijack the complex during cellular infection. To modulate and probe its function we have created a novel series of macrocyclic peptides that bind Retromer with high affinity and specificity. Crystal structures show the majority of cyclic peptides bind to Vps29 via a Pro-Leu-containing sequence, structurally mimicking known interactors such as TBC1D5, and blocking their interaction with Retromer in vitro and in cells. By contrast, macrocyclic peptide RT-L4 binds Retromer at the Vps35-Vps26 interface and is a more effective molecular chaperone than reported small molecules, suggesting a new therapeutic avenue for targeting Retromer. Finally, tagged peptides can be used to probe the cellular localisation of Retromer and its functional interactions in cells, providing novel tools for studying Retromer function.

biochemistry↗

RTN3 inhibits RIGI-I-mediated antiviral responses by impairing TRIM25-mediated K63-linked polyubiquitination

Upon viral RNA recognition, the RIG-I signalosome continuously generates IFNs and cytokines, leading to neutrophil recruitment and inflammation. Thus, attenuation of excessive immune and inflammatory responses is crucial to restore immune homeostasis and prevent unwarranted damage, yet few proresolving mediators have been identified. In the present study, we demonstrated that RTN3 is strongly upregulated during RNA viral infection and acts as an inflammation-resolving regulator. Increased RTN3 aggregates on the endoplasmic reticulum and interacts with both TRIM25 and RIG-I, subsequently impairing K63-linked polyubiquitination and resulting in both IRF3 and NF-{kappa}B inhibition. Rtn3 overexpression in mice causes an obvious inflammation resolving phenomenon when challenged with VSV, Rtn3-overexpressing mice display significantly decreased neutrophil numbers and inflammatory cell infiltration, which is accompanied by reduced tissue edema in the liver and thinner alveolar interstitium. Taken together, our findings identify RTN3 as a conserved proresolving mediator of immune and inflammatory responses and provide insights into the negative feedback that maintains immune and inflammatory homeostasis. SummaryRTN3 is upregulated upon RNA viral infection due to inflammation and ER stress, in turn suppresses antiviral responses by impairing TRIM25-mediated RIG-I K63-linked polyubiquitination and consequently decreases neutrophil populations and inflammatory infiltration, representing a novel mechanism of negative inflammatory resolution.

immunology↗

AKAP79/150 coordinates leptin-induced PKA activation to regulate KATP channel trafficking in pancreatic β-cells

The adipocyte hormone leptin regulates glucose homeostasis both centrally and peripherally. A key peripheral target is the pancreatic {beta}-cell, which secretes insulin upon glucose stimulation. Leptin suppresses glucose-stimulated insulin secretion by promoting trafficking of KATP channels to the {beta}-cell surface, which increases K+ conductance and causes {beta}-cell hyperpolarization. Here we investigate the signaling mechanism underlying leptin-induced KATP channel translocation with a focus on protein kinase A (PKA). Using FRET-based PKA activity reporters, we show that leptin increases PKA activity at the cell membrane via a signaling pathway involving NMDA receptors, CaMKK{beta} and AMPK. Genetic knockdown and rescue experiments reveal that leptin activation of PKA requires tethering of PKA to the membrane-targeted PKA-anchoring protein AKAP79/150. Interestingly, disrupting protein phosphatase 2B (PP2B) anchoring to AKAP79/150, known to elevate basal PKA signaling, increases surface KATP channels. Our findings uncover a novel role of AKAP79/150 in coordinating leptin and PKA signaling to regulate {beta}-cell function.

cell biology↗

Dynamic integration and segregation of amygdala subregional functional circuits linking to physiological arousal

The dynamical organization of brain networks is essential to support human cognition and emotion for rapid adaption to ever-changing environment. As the core nodes of emotion-related brain circuitry, the basolateral amygdala (BLA) and centromedial amygdala (CMA) as two major amygdalar nuclei, are recognized to play distinct roles in affective functions and internal states, via their unique connections with cortical and subcortical structures in rodents. However, little is known how the dynamical organization of emotion-related brain circuitry reflects internal autonomic responses in humans. Using resting-state functional magnetic resonance imaging (fMRI) with K-means clustering approach in a total of 79 young healthy individuals (cohort 1: 42; cohort 2: 37), we identified two distinct states of BLA- and CMA-based intrinsic connectivity patterns, with one state (integration) showing generally stronger BLA- and CMA-based intrinsic connectivity with multiple brain networks, while the other (segregation) exhibiting weaker yet dissociable connectivity patterns. In an independent cohort 2 of fMRI data with concurrent recording of skin conductance, we replicated two similar dynamic states and further found higher skin conductance level in the integration than segregation state. Moreover, machine learning-based Elastic-net regression analyses revealed that time-varying BLA and CMA intrinsic connectivity with distinct network configurations yield higher predictive values for spontaneous fluctuations of skin conductance level in the integration than segregation state. Our findings highlight dynamic functional organization of emotion-related amygdala nuclei circuits and networks and its links to spontaneous autonomic arousal in humans.

neuroscience↗

Individual and combined effects of Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) on striato-cortical connectivity in the human brain

Cannabidiol (CBD) and {Delta}9-tetrahydrocannabinol (THC) are two major constituents of cannabis with contrasting mechanisms of action. THC is the major psychoactive, addiction-promoting, and psychotomimetic compound, while CBD may have somewhat opposite effects. The brain effects of these drugs alone and in combination are poorly understood. In particular the striatum is implicated in the pathophysiology of several psychiatric disorders, but it is unclear how THC and CBD influence striato-cortical connectivity. Across two placebo-controlled, double-blind studies, we examine the effects of THC, CBD, and THC+CBD on the functional connectivity of striatal sub-divisions (associative, limbic, and sensorimotor) using resting-state functional Magnetic Resonance Imaging (fMRI) and seed-based functional connectivity analyses. Study 1 (N=17; inhaled 8mg THC, 8mg THC+10mg CBD, placebo) showed strong disruptive effects of both THC and THC+CBD conditions on connectivity in the associative and sensorimotor networks, but a specific effect of THC in the limbic striatum, which was alleviated in the THC+CBD condition such that it did not differ from placebo. In Study 2 (N=23, oral 600mg CBD, placebo) CBD increased connectivity in the associative network, but relatively minor decreases/disruptions were found in the limbic and sensorimotor. In conclusion, THC strongly disrupts striato-cortical networks, and this effect is selectively mitigated in the limbic striatum when co-administered with CBD. When administered alone, 600mg oral CBD has a more complex effect profile of relative increases and decreases in connectivity. The insula emerges as a key region affected by cannabinoid-induced changes in functional connectivity, with potential implications for understanding cannabis related disorders, and the development of cannabinoid therapeutics.

neuroscience↗

Sequential ER stress and inflammatory responses are induced by SARS-CoV-2 ORF3 through ERphagy

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have resulted in a number of severe cases of COVID-19 and deaths worldwide. However, knowledge of SARS-CoV-2 infection, diseases and therapy remains limited, underlining the urgency of fundamental studies and drug development. Studies have shown that induction of autophagy and hijacking of autophagic machinery are essential for infection and replication of SARS-CoV-2; however, the mechanism of this manipulation and function of autophagy during SARS-CoV-2 infection remain unclear. In the present study, we identified ORF3 as an inducer of autophagy and revealed that ORF3 localizes to the ER and induces FAM134B-related ERphagy through the HMGB1-Beclin1 pathway. As a consequence, ORF3 induces ER stress and inflammatory responses through ERphagy and sensitizes cells to ER stress-induced cell death, suggesting that SARS-CoV-2 ORF3 hijacks ERphagy and then harms ER homeostasis to induce inflammatory responses through excessive ER stress. These findings reveal a sequential induction of ERphagy, ER stress and acute inflammatory responses during SARS-CoV-2 infection and provide therapeutic potential for ERphagy and ER stress-related drugs for COVID-19 treatment and prevention. ImportanceSARS-CoV-2 infection and replication require autophagosome-like double-membrane vacuoles. Inhibition of autophagy suppresses viral replication, indicating the essential role of autophagy in SARS-CoV-2 infection. However, how SARS-CoV-2 hijacks autophagy and the function of autophagy in the disease progression remain unknown. Here, we reveal that SARS-CoV-2 ORF3 induces ERphagy and consequently induces ER stress to trigger acute inflammatory responses and enhance sensitivity to ER stress-induced apoptosis. Our studies uncover ERphagy-induced inflammatory responses during SARS-CoV-2 infection and provide a promising therapeutic approach for treating SARS-CoV-2 infection and inflammatory responses in COVID-19 by manipulating autophagy and ER stress.

microbiology↗

Methyltransferase SMYD5 Exaggerates IBD by Downregulating Mitochondrial Functions via Post-translational Control of PGC-1α Stability

Background and AimsThe expression and role of methyltransferase SET and MYND domain-containing protein 5 (SMYD5) in inflammatory bowel diseases (IBD) is completely unknown. Here, we investigated the role and the underlying mechanism of epithelial SMYD5 in IBD pathogenesis and progression. MethodsThe expression and subcellular localization of SMYD5 and peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) were examined by Western blot analysis, immunofluorescence staining, and immunohistochemistry in intestinal epithelial cells (IECs) and in colon tissues from human IBD patients and mice with experimental colitis. Mice with Smyd5 conditional knockout in IECs and littermate controls were subjected to DSS-induced experimental colitis and the disease severity and inflammation were assessed. SMYD5-regulated mitochondrial biogenesis was examined by RT-qPCR and transmission electron microscopy and mitochondrial oxygen consumption rate was measured in a Seahorse Analyzer system. The interaction between SMYD5 and PGC-1 was determined by co-immunoprecipitation assay. PGC-1 degradation and turnover (half-life) were analyzed by cycloheximide chase assay. SMYD5-mediated PGC-1 methylation was measured via in vitro methylation followed by mass spectrometry to identify the specific lysine residues that were methylated. ResultsUp-regulated SMYD5 and down-regulated PGC-1 were observed in IECs from IBD patients and mice with experimental colitis. However, Smyd5 depletion in IECs protected mice from DSS-induced colitis. SMYD5 was critically involved in regulating mitochondrial biology such as mitochondrial biogenesis, respiration, and apoptosis. Mechanistically, SMYD5 regulated mitochondrial functions in a PGC-1 dependent manner. Further, SMYD5 mediated lysine methylation of PGC-1 and facilitated its ubiquitination and proteasomal degradation. ConclusionSMYD5 attenuates mitochondrial functions in IECs and promotes IBD progression by enhancing the proteasome-mediated degradation of PGC-1 protein in methylation-dependent manner. Strategies to decrease SMYD5 expression and/or increase PGC-1 expression in IECs might be a promising therapeutic approach to treat patients with IBD.

cell biology↗

A benchmarking study of SARS-CoV-2 whole-genome sequencing protocols using COVID-19 patient samples

The COVID-19 pandemic is a once-in-a-lifetime event, exceeding mortality rates of the flu pandemics from the 1950s and 1960s. Whole-genome sequencing (WGS) of SARS-CoV-2 plays a critical role in understanding the disease. Performance variation exists across SARS-CoV-2 viral WGS technologies, but there is currently no benchmarking study comparing different WGS sequencing protocols. We compared seven different SARS-CoV-2 WGS library protocols using RNA from patient nasopharyngeal swab samples under two storage conditions. We constructed multiple WGS libraries encompassing three different viral inputs: 1,000,000, 250,000 and 1,000 copies. Libraries were sequenced using two distinct platforms with varying sequencing depths and read lengths. We found large differences in mappability and genome coverage, and variations in sensitivity, reproducibility and precision of single-nucleotide variant calling across different protocols. We ranked the performance of protocols based on six different metrics. Our results indicated that the most appropriate protocol depended on viral input amount and sequencing depth. Our findings offer guidance in choosing appropriate WGS protocols to characterize SARS-CoV-2 and its evolution.

genomics↗

Human Identical Sequences of SARS-CoV-2 Promote Clinical Progression of COVID-19 by Upregulating Hyaluronan via NamiRNA-Enhancer Network

The COVID-19 pandemic is a widespread and deadly public health crisis. The pathogen SARS-CoV-2 replicates in the lower respiratory tract and causes fatal pneumonia. Although tremendous efforts have been put into investigating the pathogeny of SARS-CoV-2, the underlying mechanism of how SARS-CoV-2 interacts with its host is largely unexplored. Here, by comparing the genomic sequences of SARS-CoV-2 and human, we identified five fully conserved elements in SARS-CoV-2 genome, which were termed as "human identical sequences (HIS)". HIS are also recognized in both SARS-CoV and MERS-CoV genome. Meanwhile, HIS-SARS-CoV-2 are highly conserved in the primate. Mechanically, HIS-SARS-CoV-2, behaving as virus-derived miRNAs, directly target to the human genomic loci and further interact with host enhancers to activate the expression of adjacent and distant genes, including cytokines gene and angiotensin converting enzyme II (ACE2), a well-known cell entry receptor of SARS-CoV-2, and hyaluronan synthase 2 (HAS2), which further increases hyaluronan formation. Noteworthily, hyaluronan level in plasma of COVID-19 patients is tightly correlated with severity and high risk for acute respiratory distress syndrome (ARDS) and may act as a predictor for the progression of COVID-19. HIS antagomirs, which downregulate hyaluronan level effectively, and 4-Methylumbelliferone (MU), an inhibitor of hyaluronan synthesis, are potential drugs to relieve the ARDS related ground-glass pattern in lung for COVID-19 treatment. Our results revealed that unprecedented HIS elements of SARS-CoV-2 contribute to the cytokine storm and ARDS in COVID-19 patients. Thus, blocking HIS-involved activating processes or hyaluronan synthesis directly by 4-MU may be effective strategies to alleviate COVID-19 progression.

molecular biology↗

High oil accumulation in tuber of yellow nutsedge compared to purple nutsedge is associated with more abundant expression of genes involved in fatty acid synthesis and triacylglycerol storage

Yellow nutsedge is a specific plant species that contains significant amounts of both starch and oil as the main reserves in storage tuber. Its tuber can accumulate up to 35% oil of dry weight, perhaps the highest level observed in the tuber tissues of plant kingdom. To gain insight into the molecular mechanism that leads to high oil accumulation in yellow nutsedge, gene expression profiles of oil production pathways involved carbon metabolism, fatty acid synthesis, triacylglycerol synthesis, and triacylglycerol storage during tuber development were compared with purple nutsedge, a very close relative of yellow nutsedge that is poor in oil accumulation. Compared with purple nutsedge, the high oil content in yellow nutsedge was associated with much higher transcripts for seed-like oil-body proteins, almost all fatty acid synthesis enzymes, and specific key enzymes of plastid Rubisco bypass as well as malate and pyruvate metabolism. However, transcript levels for carbon metabolism toward pyruvate generation were comparable and for triacylglycerol synthesis were similar in both species. Two seed-like master transcription factors ABI3 and WRI1 were found to display similar temporal transcript patterns but be expressed at 6.5- and 14.3-fold higher levels in yellow nutsedge than in purple nutsedge, respectively. A weighted gene co-expression network analysis revealed that ABI3 is in strong transcriptional coordination with WRI1 and other key oil-related genes. Together, these results implied that plastidial pyruvate availability and fatty acid synthesis, along with triacylglycerol storage in oil body, rather than triacylglycerol synthesis in endoplasmic reticulum, are the major factors responsible for high oil production in tuber of yellow nutsedge, and ABI3 is most likely to play a critical role in regulating oil accumulation. This study will aid understanding in underlying molecular mechanism controlling carbon partitioning toward oil production in oil-rich tuber and provide valuable reference for enhancing oil accumulation in non-seed tissues of crops through genetic breeding or metabolic engineering.

plant biology↗

Transcriptional silencing of ALDH2 in acute myeloid leukemia confers a dependency on Fanconi anemia proteins

Hundreds of genes become aberrantly silenced in acute myeloid leukemia (AML), with most of these epigenetic changes being of unknown functional consequence. Here, we demonstrate how gene silencing can lead to an acquired dependency on the DNA repair machinery in AML. We make this observation by profiling the essentiality of the ubiquitin conjugation and ligation machinery in cancer cell lines using domain-focused CRISPR screening, which revealed Fanconi anemia (FA) proteins UBE2T (an E2) and FANCL (an E3) as unique dependencies in AML. We demonstrate that these dependencies are due to a synthetic lethal interaction between FA proteins and Aldehyde Dehydrogenase 2 (ALDH2), which function in parallel pathways to counteract the genotoxic effects of endogenous aldehydes. We provide evidence that DNA hypermethylation and transcriptional silencing of ALDH2 occur in a recurrent manner in human AML patient samples, which is sufficient to confer FA pathway dependency in this disease. Taken together, our study suggests that targeting of the ubiquitination reaction catalyzed by FA proteins can eliminate ALDH2-deficient AML.

cancer biology↗

Stability of the Retinoid X Receptor-alpha Homodimer in the Presence and Absence of Rexinoid and Coactivator Peptide

Differential scanning calorimetry and differential scanning fluorimetry were used to measure the thermal stability of human retinoid X receptor-alpha ligand binding domain (RXR LBD) homodimer in the absence or presence of rexinoid and coactivator peptide, GRIP-1. The apo-RXR LBD homodimer displayed a single thermal unfolding transition with a Tm of 58.7 {degrees}C and an unfolding enthalpy ({Delta}H) of 673 kJ/mol (12.5 J/g), much lower than average value (35 J/g) of small globular proteins. Using a heat capacity change ({Delta}Cp) of 15 kJ/(mol{middle dot}K) determined by measurements at different pH values, the free energy of unfolding ({Delta}G) of the native state was 33 kJ/mol at 37 {degrees}C. Rexinoid binding to the apo-homodimer increased Tm by 5 to 9 {degrees}C, and increased the {Delta}G of the native homodimer by 12 to 20 kJ/mol at 37 {degrees}C, consistent with the nanomolar dissociation constant (Kd) of the rexinoids. The increase in {Delta}G was the result of a more favorable entropic change due to interactions between the rexinoid and hydrophobic residues in the binding pocket, with the larger increases caused by rexinoids containing larger hydrophobic end groups. GRIP-1 binding to holo-homodimers containing rexinoid resulted in additional increases in {Delta}G of 14 kJ/mol, a value same for all three rexinoids. Binding of rexinoid and GRIP-1 resulted in a combined 50% increase in unfolding enthalpy, consistent with reduced structural fluidity and more compact folding observed in other published structural studies. Thermodynamic analysis thus provided a quantitative evaluation of the interactions between RXR and its agonist and coactivator.

biochemistry↗

Roles of Signaling Compounds and WRKY31 in the Defense of Pinus massoniana L. Against Dendrolimus punctatus

Dendrolimus punctatus is an important pest affecting Masson pine (Pinus massoniana L.) forests and can cause serious economic and ecological losses. WRKY transcription factors play important roles in coping with various environmental stresses. In particular, recent studies have shown that WRKY transcription factors play an important role in plant responses against herbivorous insects. However, the mechanisms underlying the actions of these genes in the defense responses of P. massoniana L. are still unclear. Our previous study provided evidence that WRKY may play an important role in the insect resistance of P. massoniana L. In this study, application of semiochemicals such as exogenous hormones and Ca2+ by spraying increased the concentrations of endogenous hormones, terpenoid synthases, and volatile substances in P. massoniana L. and effectively improved its resistance to D. punctatus. After analyzing the WRKY family of P. massoniana L., the PmWRKY31 gene was selected and studied. Yeast two-hybrid assays showed that the LP8 gene interacted with PmWRKY31. Fluorescence-based quantitative polymerase chain reaction showed that after treatment with exogenous hormones and Ca2+, the expression levels of the PmWRKY31 gene, hormonal signal-related genes, and terpene biosynthetic pathway-related genes were significantly increased, whereas the expression of the LP8 gene was decreased. Therefore, the PmWRKY31 and LP8 genes affected downstream gene expression by positively and negatively regulating the hormone signaling pathways, respectively. This result provides theoretical support for the involvement of WRKY transcription factors in the insect resistance of P. massoniana L. through their regulation of hormone signaling.

plant biology↗

PD-L1 lncRNA splice promotes lung adenocarcinoma progression via enhancing c-Myc activity

Although blockade of programmed death-ligand 1 (PD-L1) to enhance T cell immune responses shows great promise in tumor immunotherapy, the efficacy of such immune-checkpoint inhibition strategy is limited for patients with solid tumors. The mechanism underlying the limited efficacy of PD-L1 inhibitors remains unclear. Here, we show that human lung adenocarcinoma, regardless of PD-L1 protein positive or negative, all produce a long non-coding RNA isoform of PD-L1 (PD-L1-lnc) via alternative splicing, which promotes lung adenocarcinoma proliferation and metastasis. PD-L1-lnc in various lung adenocarcinoma cells is significantly upregulated by IFN{gamma} in a manner similar to PD-L1 mRNA. Both in vitro and in vivo studies demonstrate that PD-L1-lnc increases proliferation and invasion but decreases apoptosis of lung adenocarcinoma cells. Mechanistically, PD-L1-lnc directly binds to c-Myc and enhances c-Myc transcriptional activity downstream in lung adenocarcinoma cells. Our results provide targeting PD-L1-lnc-c-Myc axis as a novel strategy for lung cancer therapy.

cancer biology↗

A super-resolution protocol to correlate structural underpinnings of fast second-messenger signalling in primary cell types

Nanometre-scale cellular information obtained through super-resolution microscopies are often unaccompanied by functional information, particularly transient and diffusible signals through which life is orchestrated in the nano-micrometre spatial scale. We describe a correlative imaging protocol which allows the ubiquitous intracellular second messenger, calcium (Ca2+), to be directly visualised against nanoscale patterns of the ryanodine receptor (RyR) Ca2+ channels which give rise to these Ca2+ signals in wildtype primary cells. This was achieved by combining total internal reflection fluorescence (TIRF) imaging of the elementary Ca2+ signals, with the subsequent DNA-PAINT imaging of the RyRs. We report a straightforward image analysis protocol of feature extraction and image alignment between correlative datasets and demonstrate how such data can be used to visually identify the ensembles of Ca2+ channels that are locally activated during the genesis of cytoplasmic Ca2+ signals.

biophysics↗

Transcriptome analysis of potato leaves in response to infection with the necrotrophic pathogen Alternaria solani

The potato early blight was caused by Alternaria solani (Aso). At present, potato early blight resistant varieties are lacking. The experiment of Aso inoculation on a.k.a. Favorita showed that the content of chlorophyll decreased continuously within 2 days after inoculation. In addition, the contents of JA-Ile, SA, ABA and IAA were determined by LC-MS.The results of two defense-related hormones showed that jasmonic acid content decreased significantly, while jasmonic acid content did not change significantly. In order to understand the difference in gene expression of potatoes infected by Aso, the 24 hpi, 36 hpi and 48 hpi transcriptome were determined. The results showed that the gene annotation and cluster analysis of DEGs revealed a variety of defense responses to Aso infection, especially the plant hormone signal transduction pathway. The differential expression of 10 DEGs was confirmed by qPCR analysis. Finally, through weighted gene co-expression network analysis (WGCNA), "samonl" was determined as a key hormone-related network in the process of Aso infection in potatoes. This study provides an important clue for understanding the interaction between potato and Aso and for disease resistance breeding.

plant biology↗

A Multi-center Cross-platform Single-cell RNA Sequencing Reference Dataset

Single-cell RNA sequencing (scRNA-seq) is developing rapidly, and investigators seeking to use this technology are left with a variety of options for both experimental platform and bioinformatics methods. There is an urgent need for scRNA-seq reference datasets for benchmarking of different scRNA-seq platforms and bioinformatics methods. To be broadly applicable, these should be generated from renewable, well characterized reference samples and processed in multiple centers across different platforms. Here we present a benchmarking scRNA-seq dataset that includes 20 scRNA-seq datasets acquired either as a mixtures or as individual samples from two biologically distinct cell lines for which a large amount of multi-platform whole genome sequencing data are also available. These scRNA-seq datasets were generated from multiple popular platforms across four sequencing centers. Our benchmark datasets provide a resource that we believe will have great value for the single-cell community by serving as a reference dataset for evaluating various bioinformatics methods for scRNA-seq analyses, including but not limited to data preprocessing, imputation, normalization, clustering, batch correction, and differential analysis.

bioinformatics↗

A Bioelectric Neural Interface Towards Intuitive Prosthetic Control For Amputees

ObjectiveWhile prosthetic hands with independently actuated digits have become commercially available, state-of-the-art human-machine interfaces (HMI) only permit control over a limited set of grasp patterns, which does not enable amputees to experience sufficient improvement in their daily activities to make an active prosthesis useful. ApproachHere we present a technology platform combining fully-integrated bioelectronics, implantable intrafascicular microelectrodes and deep learning-based artificial intelligence (AI) to facilitate this missing bridge by tapping into the intricate motor control signals of peripheral nerves. The bioelectric neural interface includes an ultra-low-noise neural recording system to sense electroneurography (ENG) signals from microelectrode arrays implanted in the residual nerves, and AI models employing the recurrent neural network (RNN) architecture to decode the subjects motor intention. Main resultsA pilot human study has been carried out on a transradial amputee. We demonstrate that the information channel established by the proposed neural interface is sufficient to provide high accuracy control of a prosthetic hand up to 15 degrees of freedom (DOF). The interface is intuitive as it directly maps complex prosthesis movements to the patients true intention. SignificanceOur study layouts the foundation towards not only a robust and dexterous control strategy for modern neuroprostheses at a near-natural level approaching that of the able hand, but also an intuitive conduit for connecting human minds and machines through the peripheral neural pathways. Clinical trialDExterous Hand Control Through Fascicular Targeting (DEFT). Identifier: NCT02994160.

bioengineering↗