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Guo, F.

Publications and source records attributed to Guo, F..

At least 73 records · Page 4Linked to original sources

Cre-Lox miRNA-delivery technology optimized for inducible microRNA and gene-silencing studies in zebrafish.

While many genetic tools exist for zebrafish, this animal model is still lacking a robust gene-silencing and microRNA-delivery technology enabling spatio-temporal control and reliable traceability. We have recently demonstrated that the use of engineered pri-miR backbones can be used to both trigger stable and heritable gene knockdown and/or express microRNA(s) of choice in this organism. This approach/material fills a gap that exists in the zebrafish genetic toolbox to study microRNA biology and has the potential to be a powerful complementary tool to CRISPR-knockout and CRISPR-interference approaches by enabling conditional, traceable tissue-specific and polygenic gene-silencing. However, to date, this miRNA-expressing technology still presents important limitations. First, to trigger potent knockdown(s), multiple synthetic-miRNAs must be expressed simultaneously which compromises the co-expression of fluorescent marker(s) and knockdown traceability, thereby reducing the interest and versatility of this approach. Second, when the gene knockdown triggers significant phenotypes, like homozygous mutants with severe early phenotypes, it is difficult, if not impossible, to maintain adult transgenic carriers. Here, to solve these problems and provide a mature RNAi and microRNA-delivery technology for zebrafish research, we have generated and validated new RNAi reagents and an inducible delivery system based on the Cre/Lox technology. This new system allows the creation of asymptomatic/silent carriers, easing the production of embryos with potent knockdowns that can be traced and spatiotemporally controlled. Following this technological development, we demonstrate the utility of our approach by generating novel inducible models of spinal muscular atrophy (SMA) that open new avenues for studying the normal and pathogenic functions of the smn1 gene, as well as for establishing large-scale screens. Finally, and very importantly, the materials and techniques developed here will simplify research into microRNA biology, as well as conditions involving haploinsufficiency and multiple genes.

molecular biology↗

Dispensable regulation of brain development and myelination by Serpina3n

Serine protease inhibitor clade A member 3n (Serpina3n) or its human orthologue SERPINA3 is a secretory immune-related molecule produced primarily in the liver and brain under homeostatic conditions and upregulated in response to system inflammation. Yet it remains elusive regarding its cellular identity and physiological significance in the development of the postnatal brain. Here, we reported that oligodendroglial lineage cells are the major cell population expressing Serpina3n protein in the postnatal murine CNS. Using loss-of-function genetic tools, we found that Serpina3n conditional knockout (cKO) from Olig2-expressing cells does not significantly affect cognitive and motor functions in mice. Serpina3n depletion does not appear to interfere with oligodendrocyte differentiation and developmental myelination nor affects the population of other glial cells and neurons in vivo. Together, these data suggest that the immune-related molecule Serpina3n plays a minor role, if any, in regulating neural cell development in the postnatal brain under homeostatic conditions. We found that Serpina3n is significantly upregulated in response to oxidative stress, and it potentiates oxidative injury and cell senescence of oligodendrocytes. Our data raise the interest in pursuing its functional significance in the CNS under disease/injury conditions.

neuroscience↗

Cryo-EM structures of the tubulin cofactors reveal the molecular basis for the biogenesis of alpha/beta-tubulin

Microtubule polarity and dynamic polymerization originate from the self-association properties of the a-tubulin heterodimer. For decades, it has remained poorly understood how the tubulin cofactors, TBCD, TBCE, TBCC, and the Arl2 GTPase mediate a-tubulin biogenesis from - and {beta}-tubulins. Here, we use cryogenic electron microscopy to determine structures of tubulin cofactors bound to {beta}-tubulin. These structures show that TBCD, TBCE, and Arl2 form a heterotrimeric cage-like TBC-DEG assembly around the a-tubulin heterodimer. TBCD wraps around Arl2 and almost entirely encircles -tubulin, while TBCE forms a lever arm that anchors along the other end of TBCD and rotates -tubulin. Structures of the TBC-DEG-{beta}-tubulin assemblies bound to TBCC reveal the clockwise rotation of the TBCE lever that twists a-tubulin by pulling its C-terminal tail while TBCD holds -tubulin in place. Altogether, these structures uncover transition states in {beta}-tubulin biogenesis, suggesting a vise-like mechanism for the GTP-hydrolysis dependent a-tubulin biogenesis mediated by TBC-DEG and TBCC. These structures provide the first evidence of the critical functions of the tubulin cofactors as enzymes that regulate the invariant organization of {beta}-tubulin, by catalyzing - and {beta}-tubulin assembly, disassembly, and subunit exchange which are crucial for regulating the polymerization capacities of {beta}-tubulins into microtubules.

biochemistry↗

The role of m6A methyltransferase WTAP in inflammatory response of atherosclerosis through NF-κB/NLRP3 mediated pyroptosis

BackgroundPyroptosis is a new form of pro-inflammatory programmed cell death that has been linked to the development of atherosclerosis (AS). However, its exact mechanisms are not known. N6-methyladenosine (m6A) methylation is the commonest and most abundant epigenetic modification of eukaryotic mRNAs. m6A methylation modulates pathological and physiological processes involved in cardiovascular diseases. However, the exact mechanism by which it regulates inflammation in AS is unclear. MethodsIn this study, the level of m6A and WTAP in CHD was explored. To determine the effect of WTAP on the release of pyrolysis-related proteins and pro-inflammatory cytokines, the expression of WTAP in lipopolysaccharide (LPS)-treated endothelial cells was silenced. Pyroptosis-related proteins and pro-inflammatory cytokines were quantified in the presence of NLRP3 shRNA (shNLRP3) and NF-kB shRNA (shNF-kB(p50)). The interaction of NF-kB and NLRP3 was examined through immunoprecipitation (CO-IP), immunofluorescence (IF) and GST-pull down assays. ResultIt was observed that lipopolysaccharide (LPS) induced Nod-like receptor protein 3 (NLRP3)-mediated pyroptosis and inflammation, both of which were abolished through the knockdown of WTAP. Interestingly, our results indicated that WTAP enhanced the function of nuclear factor {kappa}B (NF-{kappa}B) p50 (an NF-{kappa}B subunit) and that p50 could interact with NLRP3 in endothelial cells. ConclusionIn conclusion, these results suggested that WTAP in the formation of pyroptosis and inflammation in endothelial cells exposed to LPS stress by activating the NF-{kappa}B/NLRP3 signaling pathway. These findings demonstrate the mechanism of WTAP regulation during the progression of AS.

immunology↗

Single-cell RNA-seq analysis profiling characterizes differences in cell composition and physiology between normal tissue, treatment-naive, and cisplatin-treated ovarian cancer

BackgroundIntense efforts have focused on identifying heterogeneity of the cellular composition in ovarian cancer. However, tissue composition and physiological conditions of cancer cells in cisplatin-sensitive ovarian cancer remains largely unknown. Moreover, comparisons of different cellular states in normal tissue, in treatment naive ovarian cancer, and in cisplatin-treated tissue after adjuvant therapy of cisplatin-sensitive ovarian cancer at the single-cell level might offer clues for ovarian cancer treatment and prevention of cisplatin-resistance formation. MethodsSingle-cell transcriptome sequencing of a cisplatin-treated ovarian cancer was performed. Data sets of non-tumorous ovarian tissues and treatment-naive ovarian cancer were downloaded from the European Genome-phenome Archive (accession number EGAS00001004987). Quality control, batch effect correction, integration, and clustering analysis of the integrated single-cell transcriptome data was done. Cell subsets were annotated based on surface marker phenotypes. Finally, the proportions of subclusters, the immune cell population, and the potential biological processes among different cellular states were compared. ResultsSixteen distinct cell subsets were identified from the integrated single-cell transcriptome sequencing data of a pool of all tissues. The composition of the three different tissue types was characterized. The proportion of fibroblasts in cisplatin-treated ovarian tumor was remarkably lower than in treatment-naive ovarian tumor (1.33% vs. 13.53%, p < 0.05). Moreover, each subjects sample had differing relative proportions of the identified cell types. In primary untreated ovarian cancer, the prevalent immune cells were B cells and myeloid-related immunosuppressive M2 macrophages. However, there were less B cells and myeloid-related immunosuppressive M2 macrophages after cisplatin-treatment, while significantly more T cells were found. The physiological cellular state in primary untreated ovarian tumors was associated with dysfunctional gene expression and modulation of cellular homeostasis, while cells from cisplatin-treated tumor showed more activation of immune and inflammatory genes as compared to healthy ovarian tissue. ConclusionOur molecular gene expression analysis allowed for the separation and identification of differences in normal ovarian tissues, treatment-naive, and cisplatin-sensitive ovarian cancer cell populations at single-cell resolution. We identified different cell type composition and discriminative marker expression concerning specific cell subsets and identified differences among their physiological cell states. This knowledge may open new possibilities for elucidating important pathogenetic features and therapeutic strategies for treating ovarian cancer.

cancer biology↗

The laminar pattern of proprioceptive activation in human primary motor cortex

The primary motor cortex (M1) has traditionally been viewed as a motor output generator. However, its vital role in proprioceptive somatosensation is increasingly being recognized. Yet, our understanding of proprioceptive somatosensation in M1 at the laminar scale is limited, largely due to methodological challenges. Empirical findings in primates and rodents suggest a pronounced role of superficial cortical layers, but the involvement of deep layers has yet to be examined in humans. Submillimeter resolution fMRI has emerged in recent years, paving the way for the study of layer-dependent activity in humans (laminar fMRI). In the present study, laminar fMRI was employed to investigate the laminar pattern of proprioceptive somatosensation on M1 deep layer activation using passive finger movements as proprioceptive stimulation. Significant M1 deep layer activation was observed in response to proprioceptive stimulation across 10 healthy subjects using vascular space occupancy (VASO) at 7T. For further validation, two additional subjects were scanned using a balanced steady-state free precession (bSSFP) sequence with ultrahigh (0.3 mm) in-plane resolution, yielding converging results. These results were interpreted in the light of previous laminar fMRI studies and the active inference account of motor control. We suggest that a considerable proportion of M1 deep layer activation is due to proprioceptive influence and that deep layers of M1 constitute a key component in proprioceptive circuits.

neuroscience↗

Brief change in dopamine activity during consolidation impairs long-term memory via sleep disruption

Sleep disturbances are associated with poor long-term memory (LTM) formation, yet the underlying cell types and neural circuits involved have not been fully decoded. Dopamine neurons (DANs) are involved in memory processing at multiple stages. Here, using both male and female flies, Drosophila melanogaster, we show that, during the first few hours of memory consolidation, disruption of basal activity of a small subset of protocerebral anterior medial DANs (PAM-DANs), by either brief activation or inhibition of the two dorsal posterior medial (DPM) neurons, impairs 24 h LTM. Interestingly, these brief changes in activity using female flies result in sleep loss and fragmentation, especially at night. Importantly, pharmacological rescue of sleep after manipulation restores LTM. A specific subset of PAM-DANs (PAM-1) that synapse onto DPM neurons specify the microcircuit that links sleep and memory. MBON-1 also contributes to the integration of sleep and memory by acting as an additional parallel circuit. PAM-DANs, including PAM-1, form functional synapses onto DPM mainly via two dopamine receptor subtypes. Dop1R1 primarily mediates the link between sleep and memory. This PAM-1 to DPM microcircuit exhibits a synchronized, transient, post-training change in activity during the critical memory consolidation window, suggesting an effect of this microcircuit on maintaining the sleep necessary for LTM consolidation. Our results provide a new molecular and circuit basis for the complex relationship between sleep and memory.

neuroscience↗

Democratizing access to microfluidics: Rapid prototyping of capillary microfluidics with a low-cost masked stereolithography 3D printer

Microfluidics offer user-friendly liquid handling for a range of biochemical applications. 3D printing microfluidics is rapid and cost-effective compared to conventional cleanroom fabrication. Typically, microfluidics are 3D printed using digital light projection (DLP) stereolithography (SLA), but many models in use are expensive ([&ge;]$10,000 USD), limiting widespread use. Recent liquid crystal display (LCD) technology advancements have provided inexpensive (<$500) SLA 3D printers with sufficient pixel resolution for microfluidic applications. However, there are only a few demonstrations of microfluidic fabrication, limited validation of print fidelity, and no direct comparisons between LCD and DLP printers. We compared a 40 {micro}m pixel resolution DLP printer ([~]$18,000 USD) with a 34.4 {micro}m (<$380) LCD-SLA printer. Consistent with prior work, we observed linear trends between designed and measured channel widths [&ge;] 4 pixels on both printers, so we calculated accuracy above this size threshold. Using a standard IPA wash resin and optimized parameters for each printer, the average error between designed and measured widths was 2.11 {+/-} 1.26% with the DLP printer and 15.4 {+/-} 2.57% with the 34.4 {micro}m LCD printer. The average coefficient of variation [CV] was [~]2% for both printers. Printing with optimized conditions for a low-cost water wash resin designed for LCD-SLA printers resulted in an average error of 2.53 {+/-} 0.94% with the 34.4 {micro}m LCD printer and 5.35 {+/-} 4.49% with a 22 {micro}m LCD printer. We characterized additional parameters including surface roughness, channel perpendicularity, and light intensity uniformity, and as an application of LCD-printed devices, we demonstrated consistent flow rates in capillaric circuits for self-regulated and self-powered delivery of multiple liquids. In conclusion, LCD printers are an inexpensive alternative for fabricating microfluidics, with minimal differences in fidelity and accuracy compared with a 20X more expensive DLP printer.

scientific communication and education↗

Thermoplasmonic modulation of cardiomyocytes activity with local temperature read-out

Cardiomyocyte beating rate modulation is required in multiple in vitro assays and it is usually done by electrical or optogenetic methods. In this work, we develop and characterize a light-based strategy to modulate the cardiomyocyte beating rate by near-infrared (NIR) controlled plasmonic stimulation. For this purpose, gold nanorods (GNRs) acting as plasmonic heaters and silica-coated quantum dots (QDs) as nanothermometers are attached to surfaces used for cardiomyocyte cultures, while the cell electrophysiological activity is visualized by monitoring calcium transients via calcium imaging. This system is capable of modulating cardiac activity with near infrared-controllable plasmonic heating while measuring local temperature changes owing to the temperature-dependent fluorescence of silica-coated QDs. Table of Contents (TOC) O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/554091v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@4325fcorg.highwire.dtl.DTLVardef@72c48dorg.highwire.dtl.DTLVardef@c60849org.highwire.dtl.DTLVardef@14a1e27_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

The longitudinal single-cell panorama of cynomolgus monkey ovary throughout lifespan revealed a conserved ovarian clock between primates

Ovarian function is critical for female fertility and impacts reproductive longevity. It is of great importance to accurately predict the aging process within the ovary for fertility assessment and disease diagnosis. However, cell metrics for evaluating the ovarian aging rate are still in urgent need, and molecular insights into ovarian development and dysfunction during the primate life course are also limited. Here, we reported large-scale ovarian cell atlas of consecutive development of cynomolgus monkeys across 22 years with 20 time points, covering the foetal, newborn, prepubertal, pubertal, adult, perimenopausal and menopausal stages. We characterized and validated distinct molecular signatures of each cluster of cells within primate ovaries, and uncovered a previously undocumented RHOXF1-positive oocyte type during primordial follicle assembly in primates. Furthermore, the constitution and developmental trajectories of primate germ cells, granulosa cells and stromal / theca cells were also elucidated, and their precursors were identified. More importantly, dynamics of cellular compositions were unravelled through the ovarian development, featured by granulosa, epithelial, stromal, and immune cells that showed strong temporal heterogeneity spanning lifetime, whilst referred to the key function during the corresponding stages. Based on the correlations of each cell type with age and stage-specific molecular dynamics, we further constructed a transcriptomic ovarian clock which could perceive an effective biological age prediction of the ovary and further applied to humans. The findings reveal granulosa, epithelial, and stromal cells as the highest performance predictors of ovarian biological age, while highlighting the crucial role of AGE-RAGE and Relaxin signaling pathways in regulating ovarian aging. Our work not only provide valuable resource for obtaining insights into the development, aging and dysfunction of key organs, but also establish a transcriptomic clock to predict biological ovarian aging thus to be potential clinical implementation in future.

developmental biology↗

Pan-genome and Haplotype Map of Cultivars and Their Wild Ancestors Provides Insights into Adaptive Evolution of Cassava (Manihot esculenta Crantz)

Cassava is the most important starch sources, a tropical model crop. We constructed nearly T2T genomes of cultivar AM560, wild ancestors FLA4047 and W14, pan-genome of 24 representatives and a clarified evolutionary tree with 486 accessions. Comparison of SVs and SNVs between the ancestors and cultivated cassavas revealed predominant expansion, contraction of genes and gene families. Significantly selective sweeping occurred in the cassava genomes in 122 footprints with 1,519 candidate domestication genes. We identified selective mutations in MeCSK and MeFNR3 promoting photoreaction associated with MeNADP-ME of C4 assimilation in modern cassava. Co-evolved retardation of floral primordia and initiation of storage roots arose from MeCOL5 mutants with altered bindings to MeFT1, MeFT2 and MeTFL2. MebHLHs evolved to regulate the biosynthesis, transport and endogenous remobilization of cyanogenic glucosides, with new functionalities of MeMATE1, MeGTR in selected sweet cassava. These findings enhanced comprehensive knowledge and database on the evolution and breeding of cassava. HIGHLIGHTSO_LIThree nearly T2T cassava genomes of cultivar AM560 and its wild ancestors FLA4047 and W14. C_LIO_LIA species-level cassava panSV haplotype map across 346,322 structural variations over 31,362 gene families and 96,032,008 SNPs and InDels variations globally and a clarified evolutionary tree with 486 accessions. C_LIO_LISelective mutations in MeCSK and MeFNR3 promoted photoreaction associated with MeNADP-ME of C4 assimilation shaped the C3-C4 intermediate photosynthesis of modern cassava. C_LIO_LICoevolution of floral primordia contrary to initiated storage root is pivotal for the domestication of cassava, and arose from MeCOL5 mutants altered the binding with MeFT1, MeFT2 (SP6A), and MeTFL2. C_LI

systems biology↗

Graded FGF activity patterns distinct cell types within the apical sensory organ of the sea anemone Nematostella vectensis

Bilaterian animals have evolved complex sensory organs comprised of distinct cell types that function coordinately to sense the environment. Each sensory unit has a defined architecture built from component cell types, including sensory cells, non-sensory support cells, and dedicated sensory neurons. Whether this characteristic cellular composition is present in the sensory organs of non-bilaterian animals is unknown. Here, we interrogate the cell type composition and gene regulatory networks controlling development of the larval apical sensory organ in the sea anemone Nematostella vectensis. Using single cell RNA sequencing and imaging approaches, we reveal two unique cell types in the Nematostella apical sensory organ, GABAergic sensory cells and a putative non-sensory support cell population. Further, we identify the paired-like (PRD) homeodomain gene prd146 as a specific sensory cell marker and show that Prd146+ sensory cells become post-mitotic after gastrulation. Genetic loss of function approaches show that Prd146 is essential for apical sensory organ development. Using a candidate gene knockdown approach, we place prd146 downstream of FGF signaling in the apical sensory organ gene regulatory network. Further, we demonstrate that an aboral FGF activity gradient coordinately regulates the specification of both sensory and support cells. Collectively, these experiments define the genetic basis for apical sensory organ development in a non-bilaterian animal and reveal an unanticipated degree of complexity in a prototypic sensory structure.

developmental biology↗

Opposing implications of co-evolutionary lineages and traits of gut microbiome on human health status

Little is known about the co-evolutionary history of the human gut microbe and its relevance to host physiology. Here, we constructed a gut prokaryotic genomic database of wild primates (pSGBs) and compared it with the human gut prokaryotic database (hSGBs) to define shared co-evolutionary clusters (SCEC-hSGBs) and co-evolutionary traits of hSGBs. We analyzed the evolutionary trends of specific functions like carbohydrate-active enzymes and antibiotic resistance in hSGBs and uncovered host-jumping events and genome reduction tendencies in SCEC-hSGBs. Intriguingly, the SCEC-hSGBs and the super enrichers of the traits (SUEN-hSGBs), which are putatively partially derived from carnivores, showed opposite implications for host health status. Specifically, SUEN-hSGBs are enriched in various diseases, showing a negative correlation with gut biodiversity and disproportionate contributions to the known health-negative marker taxa and metabolite. Our study provides insight into the origin and adaptability of human gut microbes and references for developing probiotics and microbiome-based host health prediction.

microbiology↗

Synchrony of Bird Migration with Avian Influenza Global Spread; Implications for Vulnerable Bird Orders

Highly pathogenic avian influenza virus (HPAIV) A H5 clade 2.3.4.4 has caused worldwide outbreaks in domestic poultry, occasional spillover to humans, and increasing deaths of diverse species of wild birds since 2014. Wild bird migration is currently acknowledged as an important ecological process contributing to the global dispersal of HPAIV H5. However, it is unclear how seasonal bird migration facilitates global virus dispersal, and which avian species are exposed to HPAI H5 clade 2.3.4.4 viruses and where. To shed light on ongoing global outbreaks, we sought to explore these questions through phylodynamic analyses based on empirical data of bird movement tracking and virus genome sequences. First, based on viral phylogeography and bird migration networks, we demonstrate that seasonal bird migration can explain salient features of the global dispersal of clade 2.3.4.4. Second, we detect synchrony between the seasonality of bird annual cycle phases and virus lineage movements. We reveal the differing vulnerable bird orders at geographical origins and destinations of HPAIV H5 lineage movements. Notably, we highlight the potential importance of relatively under-discussed Suliformes and Ciconiiformes, in addition to Anseriformes and Charadriiformes, in virus lineage movements. Our study provides a phylodynamic framework that links the bird movement ecology and genomic epidemiology of avian influenza; it highlights the importance of integrating bird behaviour and life history in avian influenza studies.

ecology↗

Interspecies blastocyst complementation generates functional rat cell-derived forebrain tissues in mice

Interspecies organogenesis via blastocyst complementation provides a unique platform to study development in an evolutionarily context and holds potential to overcome world-wide organ shortages1. By using this technique, rat pancreas, thymus, heart, and eye tissues have been generated in mice2-4. To date, however, xeno-generation of brain tissues has not been achieved through blastocyst complementation. Here, we developed an optimized one-step blastocyst complementation strategy based on C-CRISPR5, which facilitated rapid screening of candidate genes to support blastocyst complementation. Among the seven WNT pathway-related genes selected for targeting, only Dkk1 or Hesx1 deficiency supported forebrain complementation by blastocyst injection of mouse embryonic stem cells (mESCs). Further, injecting rat ESCs (rESCs) into mouse blastocysts deficient for Hesx1 but not Dkk1 supported the development of adult chimeric forebrains comprised a large proportion of rat cells that were structurally and functionally similar to the mouse forebrains. Our analysis revealed that the rESC-derived forebrains developed along the spatial-temporal trajectory with the mouse forebrains rather than rat forebrains, but gene expression profiles of rESC-derived nerve cells surprisingly maintained the characteristics of the rat cells. We noted that the chimeric rate gradually decreased as development progressed, suggesting xenogeneic barriers during mid-to-late prenatal development. Interspecies forebrain complementation opens the door for studying evolutionarily conserved and divergent mechanisms underlying brain development and cognitive function. The C-CRIPSR based IBC strategy developed here holds great potential to broaden the study and application of interspecies organogenesis.

developmental biology↗

Bioorthogonal photocatalytic quinone methide decaging for cell-cell interaction labeling

Cell-cell interactions (CCIs) play crucial roles in directing diverse biological processes in multicellular organisms, making the high-sensitivity and selectivity characterization of the diverse CCIs in high demand yet still challenging. We herein introduced a bioorthogonal photocatalytic quinone methide decaging-enabled cell-cell interaction labeling strategy (CAT-Cell) for sensitive and spatiotemporally resolved profiling of multitype CCIs. By adapting an optimized quinone methide probe for interacting cell labeling, we demonstrated the excellent capacity of CAT-Cell for capturing CCIs directed by various receptor-ligand pairs (e.g., CD40-CD40L, TCR-pMHC) and further showed its compatibility with tumor-specific targeting systems. Finally, we used CAT-Cell to detect cytotoxic cells (e.g., antigenspecific T cells, Natural Killer cells) in mouse models containing splenocyte mixtures and tumor samples. By leveraging the bioorthogonal photocatalytic decaging chemistry, CAT-Cell offers as a nongenetic, non-invasive and universal toolbox for profiling diverse CCIs under physiological-relevant settings.

biochemistry↗

Brain Organoid Computing for Artificial Intelligence

Brain-inspired hardware emulates the structure and working principles of a biological brain and may address the hardware bottleneck for fast-growing artificial intelligence (AI). Current brain-inspired silicon chips are promising but still limit their power to fully mimic brain function for AI computing. Here, we develop Brainoware, living AI hardware that harnesses the computation power of 3D biological neural networks in a brain organoid. Brain-like 3D in vitro cultures compute by receiving and sending information via a multielectrode array. Applying spatiotemporal electrical stimulation, this approach not only exhibits nonlinear dynamics and fading memory properties but also learns from training data. Further experiments demonstrate real-world applications in solving non-linear equations. This approach may provide new insights into AI hardware.

bioengineering↗

Human subcortical pathways automatically detect collision trajectory without attention and awareness

Detecting imminent collisions is essential for our survival and is likely supported by evolutionarily conserved mechanisms in the brain. Using high-resolution 7T fMRI, we investigated subcortical pathways for detecting collision trajectories in healthy human subjects and hemianopic patients. When healthy participants focused their attention on a central fixation task, their superior colliculus (SC), ventromedial pulvinar (vmPul) and ventral tegmental area (VTA) elicited stronger responses to a peripheral object approaching on head-collision courses compared to near-miss trajectories. Correlation and path analyses of collision-sensitive responses revealed collision sensitivity in the SC-vmPul and SC-VTA pathways without attention and cortical influence. Both behavioral performance and SC responses showed higher sensitivity to looming stimuli from the upper visual field. For hemianopic patients with unilateral lesions of the geniculostriate pathway, the ipsilesional SC, vmPul and VTA showed collision sensitivity to looming stimuli in their blind visual field, in the absence of their awareness. Stronger responses in the SC were also associated with better detection performance of the collision events. These findings clearly demonstrate that human tectofugal pathways, without attention and awareness, automatically detects approaching objects on a collision course, supporting blindsight to impending visual threats. HighlightsO_LISC-vmPul and SC-VTA pathways show collision sensitivity without attention and cortical influence in healthy participants. C_LIO_LIBoth behavioral performance and SC responses show higher sensitivity to looming stimuli from the upper visual field. C_LIO_LIThe ipsilesional SC, vmPul and VTA of hemianopic patients automatically detects collision trajectories in their blind visual field without awareness. C_LIO_LISC response is associated with "blindsight" detection of impending collisions. C_LI

neuroscience↗