Biology subjects

Ren, J.

Publications and source records attributed to Ren, J..

At least 91 records · Page 5Linked to original sources

bioRxiv2023

Comparison of chronic aerosol inhalation with combustible cigarette and e-cigarette on the psychiatric behaviors and neuroimmune profile in mice

With the worldwide use of electronic cigarettes (e-cigarettes) as a substitution for tobacco, the effects of e-cigarette vapor exposure on human health have been investigated. However, the comparison of long-term effects of aerosol inhalation with combustible cigarette and e-cigarette on the psychiatric behaviors has not been fully revealed. The present study examines the distinct effects of combustible cigarette and e-cigarette on anxiety, depression, cognition, and social behaviors. Here we found that the combustible cigarette induced the higher level of anxiety after long-term inhalation compared to the e-cigarettes with or without the tobacco flavor. Since the mechanism of action on the psychiatric behaviors entails the alterations on the neuroimmune-sensors and principal regulators such as glial cells, we further profiled the alterations of microglia and astrocytes by chronic inhalation of combustible tobacco cigarette, specifically the negative correlations between the IBA-1 level in the locus coeruleus (LC) and the latency to nest in VLT; as well as the GFAP level in LC and the open arm time in EPM were observed. Our current data provided an insight into the less impact of e-cigarettes on the anxiety-like behaviors and neuroimmune activation compared to combustible tobacco cigarettes which is not related to the flavor in e-cigarette, and the modulation on the neuroimmune signals in LC could be a therapeutic target for smoking-related anxiety.

animal behavior and cognition↗

bioRxiv2023

Single phage proteins sequester TIR- and cGAS-generated signaling molecules

Prokaryotic anti-phage immune systems use TIR (toll/interleukin-1 receptor) and cGAS (cyclic GMP-AMP synthase) enzymes to produce 1-3/1-2 glycocyclic ADPR (gcADPR) and cyclid di-/tri-nucleotides (CDNs and CTNs) signaling molecules that limit phage replication, respectively 1-3. However, how phages neutralize these common systems is largely unknown. Here, we show that Thoeris anti-defense proteins Tad1 4 and Tad2 5 both have anti-CBASS activity by simultaneously sequestering CBASS cyclic oligonucleotides. Strikingly, apart from binding Thoeris signals 1-3 and 1-2 gcADPR, Tad1 also binds numerous CBASS CDNs/CTNs with high affinity, inhibiting CBASS systems using these molecules in vivo and in vitro. The hexameric Tad1 has six binding sites for CDNs or gcADPR, which are independent from two high affinity binding sites for CTNs. Tad2 also sequesters various CDNs in addition to gcADPR molecules, inhibiting CBASS systems using these CDNs. However, the binding pockets for CDNs and gcADPR are different in Tad2, whereby a tetramer can bind two CDNs and two gcADPR molecules simultaneously. Taken together, Tad1 and Tad2 are both two-pronged inhibitors that, alongside anti-CBASS protein 2, establish a paradigm of phage proteins that flexibly sequester a remarkable breadth of cyclic nucleotides involved in TIR- and cGAS-based anti-phage immunity.

microbiology↗

bioRxiv2023

scDILT: a model-based and constrained deep learning framework for single-cell Data Integration, Label Transferring, and clustering

The scRNA-seq technology enables high-resolution profiling and analysis of individual cells. The increasing availability of datasets and advancements in technology have prompted researchers to integrate existing annotated datasets with newly sequenced datasets for a more comprehensive analysis. It is important to ensure that the integration of new datasets does not alter the cell clusters defined in the old/reference datasets. Although several methods have been developed for scRNA-seq data integration, there is currently a lack of tools that can simultaneously achieve the aforementioned objectives. Therefore, in this study, we have introduced a novel tool called scDILT, which leverages a conditional autoencoder and deep embedding clustering to effectively remove batch effects among different datasets. Moreover, scDILT utilizes homogeneous constraints to preserve the cell-type/clustering patterns observed in the reference datasets, while employing heterogeneous constraints to map cells in the new datasets to the annotated cell clusters in the reference datasets. We have conducted extensive experiments to demonstrate that scDILT outperforms other methods in terms of data integration, as confirmed by evaluations on simulated and real datasets. Furthermore, we have shown that scDILT can be successfully applied to integrate multi-omics single-cell datasets. Based on these findings, we conclude that scDILT holds great promise as a tool for integrating single-cell datasets derived from different batches, experiments, times, or interventions.

bioinformatics↗

bioRxiv2023

Estimating the Total Variance Explained by Whole-Brain Imaging for Zero-inflated Outcomes

Zero-inflated outcomes are very common in behavioral data, particularly for responses to psychological questionnaires. Modeling these challenging distributions is further exacerbated by the absence of established statistical models capable of characterizing total signals attributed to whole-brain imaging features, making the accurate assessment of brain-behavior relationships particularly formidable. Given this critical need, we have developed a novel variational Bayes algorithm that characterizes the total signal captured by whole-brain imaging features for zero-inflated outcomes . Our zero-inflated variance (ZIV) estimator robustly estimates the fraction of variance explained (FVE) and the proportion of non-null effects from large-scale imaging data. In simulations, ZIV outperformed other linear prediction algorithms. Applying ZIV to data from one of the largest neuroimaging studies, the Adolescent Brain Cognitive DevelopmentSM (ABCD) Study, we found that whole-brain imaging features have a larger FVE for externalizing compared to internalizing behavior. We also demonstrate that the ZIV estimator, especially applied to focal sub-scales, can localize key neurocircuitry associated with human behavior.

neuroscience↗

bioRxiv2023

CD4+ T cell senescence is associated with reduced reactogenicity in severe/critical COVID-19

BackgroundAging is a critical risk factor for unfavorable clinical outcomes among COVID-19 patients and may affect vaccine efficacy. However, whether the senescence of T cells impact the progression to severe COVID-19 in the elderly individuals remains unclear. MethodsBy using flow cytometry, we analyzed the frequency of senescent T cells (Tsens) in the peripheral blood from 100 elderly patients hospitalized for COVID-19 and compared the difference between mild/moderate and severe/critical illness. We also assessed correlations between the percentage of Tsens and the quantity and quality of spike-specific antibodies by ELISA, neutralizing antibody test kit and Elispot assay respectively, cytokine production profile of COVID-19 reactive T cells as well as plasma soluble factors by cytometric bead array (CBA). ResultsWe found a significant elevated level of CD4+ Tsens in severe/critical disease compared to mild/moderate illness and patients with a higher level of CD4+ Tsens (>19.78%) showed a decreased survival rate as compared to those with a lower level (<19.78%), especially in the breakthrough infection. The percentage of CD4+ Tsens was negatively correlated with spike-specific antibody titers, neutralization ability and COVID-19 reactive IL-2+ CD4+ T cells. Additionally, IL-2 producing T cells and plasma levels of IL-2 were positively correlated with antibody levels. ConclusionOur data illustrated that the percentage of CD4+ Tsens in the peripheral blood could act as an efficient biomarker for the capacity of spike-specific antibody production and the prognosis of severe COVID-19, especially in the breakthrough infection. Therefore, restoration of the immune response of CD4+ Tsens is one of the key factors to prevent severe illness and improve vaccine efficacy in older adults.

immunology↗

bioRxiv2023

High-resolution Dynamic Human Brain Neural Activity Recording Using 3T MRI

Despite extensive research over decades, a non-invasive technique capable of capturing neural activities in the human brain with high spatiotemporal resolution is still lacking. The recently proposed direct imaging of neuronal activity (DIANA) using ultrahigh-field magnetic resonance imaging (MRI) has shown promise, but the translation from anesthetized mice to awake humans poses a significant challenge. Here we present Time Resolved ImaGing of Global Electroneurophysiological Record (TRIGGER), a novel technique that enables the direct detection of neural activity in the awake human brain using 3T MRI. In 18 participants, visual responses were captured at 5-mm spatial resolution and 1.4-ms temporal resolution. Importantly, the delay in stimulus presentation reliably corresponded to the latency of neural responses on a millisecond scale. Furthermore, when stimuli were presented to one visual field, the responses in two hemispheres exhibited the expected time difference. This non-invasive mapping approach holds the potential to elucidate neural dynamics underlying human brain function and disorders.

neuroscience↗

bioRxiv2023

Phage anti-CBASS protein simultaneously sequesters cyclic trinucleotides and dinucleotides

CBASS is a common anti-phage immune system that uses cyclic oligonucleotide signals to activate effectors and limit phage replication. In turn, phages encode anti-CBASS (Acb) proteins. We recently uncovered a widespread phage anti-CBASS protein Acb2 that acts as a "sponge" by forming a hexamer complex with three cGAMP molecules. Here, we identified that Acb2 binds and sequesters many CBASS and cGAS-produced cyclic dinucleotides in vitro and inhibits cGAMP-mediated STING activity in human cells. Surprisingly, Acb2 also binds CBASS cyclic trinucleotides 333-cyclic AMP-AMP-AMP (cA3) and 333-cAAG with high affinity. Structural characterization identified a distinct binding pocket within the Acb2 hexamer that binds two cyclic trinucleotide molecules and another binding pocket that binds to cyclic dinucleotides. Binding in one pocket does not allosterically alter the other, such that one Acb2 hexamer can simultaneously bind two cyclic trinucleotides and three cyclic dinucleotides. Phage-encoded Acb2 provides protection from Type III-C CBASS that uses cA3 signaling molecules in vivo and blocks cA3-mediated activation of the endonuclease effector in vitro. Altogether, Acb2 sequesters nearly all known CBASS signaling molecules through two distinct binding pockets and therefore serves as a broad-spectrum inhibitor of cGAS-based immunity.

microbiology↗

bioRxiv2023

Neural response properties predict perceived contents and locations elicited by intracranial electrical stimulation of human auditory cortex

Intracranial electrical stimulation (iES) of auditory cortex can elicit sound experiences with a variety of perceived contents (hallucination or illusion) and locations (contralateral or bilateral side), independent of actual acoustic inputs. However, the neural mechanisms underlying this elicitation heterogeneity remain undiscovered. Here, we collected subjective reports following iES at 3062 intracranial sites in 28 patients and identified 113 auditory cortical sites with iES-elicited sound experiences. We then decomposed the sound-induced intracranial electroencephalogram (iEEG) signals recorded from all 113 sites into time-frequency features. We found that the iES-elicited perceived contents can be predicted by the early high-{gamma} features extract from sound-induced iEEG. In contrast, the perceived locations elicited by stimulating hallucination sites and illusion sites are determined by the late high-{gamma} and long-lasting features, respectively. Our study unveils the crucial neural signatures of iES-elicited sound experiences in human and presents a new strategy to hearing restoration for individuals suffering from deafness.

neuroscience↗

bioRxiv2023

Dissecting the Biophysical Origins of Activity-Stability Tradeoffs in D-amino Acid Oxidase with Enzyme Proximity-Seq

Understanding the complex relationships between enzyme sequence, folding stability and catalytic activity is crucial for applications in industry and biomedicine. However, current enzyme assay technologies are limited by an inability to simultaneously resolve both stability and activity phenotypes and to couple these to gene sequences at large scale. Here we developed Enzyme Proximity Sequencing (EP-Seq), a deep mutational scanning method that leverages peroxidase-mediated radical labeling with single cell fidelity to dissect the effects of thousands of mutations on stability and catalytic activity of oxidoreductase enzymes in a single experiment. We used EP-Seq to analyze how 6,399 missense mutations influence folding stability and catalytic activity in a D-amino acid oxidase (DAOx) from R.gracilis. The resulting datasets demonstrate activity-based constraints that limit folding stability during natural evolution, and identify hotspots distant from the active site as candidates for mutations that improve catalytic activity without sacrificing stability. EP-Seq can be extended to other enzyme classes and provides valuable insights into biophysical principles governing enzyme structure and function.

bioengineering↗

bioRxiv2023

Co-Targeting IL-6 and EGFR signaling for the treatment of schwannomatosis and associated pain

Patients with Schwannomatosis (SWN) overwhelmingly present with intractable, debilitating chronic pain. There are no effective therapies to treat SWN. The drivers of pain response and tumor progression in SWN are not clear. The pain is not proportionally linked to tumor size and is not always relieved by tumor resection, suggesting that mechanisms other than mechanical nerve compression exist to cause pain. SWN research is limited by the lack of clinically-relevant models. Here, we established novel patient-derived xenograft (PDX) models, dorsal root ganglia (DRG) imaging model, and combined with single-cell resolution intravital imaging and RNASeq, we discovered: i) schwannomas on the peripheral nerve cause macrophage influx into the DRG, via secreting HMGB1 to directly stimulate DRG neurons to express CCL2, the key macrophage chemokine, ii) once recruited, macrophages cause pain response via overproduction of IL-6, iii) IL-6 blockade in a therapeutic setting significantly reduces pain but has modest efficacy on tumor growth, iv) EGF signaling is a potential driver of schwannoma growth and escape mechanism from anti-IL6 treatment, and v) combined IL-6 and EGFR blockade simultaneously controlled pain and tumor growth in SWN models. Our findings prompted the initiation of phase II clinical trial (NCT05684692) for pain relief in patients with SWN.

neuroscience↗

bioRxiv2023

USP39 promotes hepatocellular carcinogenesis through regulating alternative splicing in cooperation with SRSF6/HNRNPC

Abnormal alternative splicing (AS) caused by alterations in spliceosomal factors is implicated in cancers. Standard models posit that splice site selection is mainly determined by early spliceosomal U1, U2 snRNPs. Whether and how other mid/late-acting spliceosome components such as USP39 modulate tumorigenic splice site choice remain largely elusive. We observed that hepatocyte-specific knock-in of USP39 promoted hepatocarcinogenesis and potently regulated splice site selection. In human liver cancer cells, USP39 promoted tumor proliferation in a spliceosome-dependent manner. USP39 depletion deregulated hundreds of AS events, including the oncogenic splice-switching of KANK2. Mechanistically, we developed a novel RBP-motif enrichment analysis and found that USP39 modulated exon inclusion/exclusion by interacting with SRSF6/HNRNPC in both humans and mice. Our data represent a paradigm for the control of splice site selection by mid/late-acting spliceosome proteins and their interacting RBPs. USP39 and possibly other mid/late-acting spliceosome proteins may represent potential prognostic biomarkers and targets for cancer therapy. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=97 SRC="FIGDIR/small/525324v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@34cbc1org.highwire.dtl.DTLVardef@2d0ee2org.highwire.dtl.DTLVardef@2c4bd6org.highwire.dtl.DTLVardef@26db00_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2022

The deacetylase dependent and independent role of HDAC3 in cardiomyopathy

BackgroundCardiomyopathy is a common disease of cardiac muscle that negatively affects cardiac function. HDAC3 commonly functions as co-repressor by removing acetyl moieties from histone tails. However, a deacetylase-independent role of HDAC3 has also been described. Cardiac deletion of HDAC3 causes reduced cardiac contractility accompanied by lipid accumulation. The molecular function of HDAC3 in cardiomyopathy remains unknown. We have used the powerful genetic tools in Drosophila to investigate the enzymatic and non-enzymatic roles of HDAC3 in cardiomyopathy. Methods and ResultsUsing the Drosophila heart model, we showed that cardiac-specific HDAC3 knockdown leads to prolonged systoles and reduced cardiac contractility. Immunohistochemistry revealed structural abnormalities characterized by myofiber disruption in HDAC3 knock down hearts. Cardiac-specific HDAC3 knockdown showed increased levels of whole body triglycerides and increased fibrosis. The introduction of deacetylase-dead HDAC3 mutant in HDAC3 KD background showed comparable results with wild type HDAC3 in aspects of contractility and Pericardin deposition. However, deacetylase-dead HDAC3 mutants failed to improve triglyceride accumulation. ConclusionsOur data indicate that HDAC3 plays a deacetylase-independent role in maintaining cardiac contractility and preventing Pericardin deposition as well as a deacetylase-dependent role to maintain triglyceride homestasis.

physiology↗

bioRxiv2022

The Cul5 E3 Ligase Complex Is a Key Negative Feedback Regulator of TCR/IL2 Signaling and Anti-Tumor Activity in CD8+ T Cells

CD8+ T cells play an important role in tumor immune surveillance and control. Better understanding of the regulation of their anti-tumor actions and improving their cytotoxic function and persistence will help advancing cancer immunotherapies. Here, we report the development of a step-wise CRISPR knockout (KO) screening strategy under the selection of TGF-{beta}, a clinically relevant immunosuppressive pressure. The screen identifies Cul5 as a negative-feedback regulator of the core signaling pathways, differentiation, and persistence of CD8+ T cell. Cul5 KO in mouse CD8+ T cells significantly improves their tumor control ability in vitro and in vivo with significant proteomic alterations that generally enhance TCR and cytokine signaling, effector function, stemness, and survival of CD8+ T cell. Mechanistically, Cul5, whose protein content and active, neddylated form increase upon TCR-stimulation, interacts with SOCS-box-containing Pcmtd2 and negatively regulates TCR and IL2/STAT5 signaling by decreasing TCR and IL2 signaling molecules. Moreover, Cul5 KO in human CD8+ T cells phenocopies that in mouse CD8+ T cells. Furthermore, KO of CTLA4 that is markedly upregulated by Cul5 KO in mouse and human CD8+ cells further enhances anti-tumor effect of Cul5 KO, and a neddylation inhibitor enhances CD8 effector activities largely dependently of Cul5. These results together not only reveal a previously unknown negative-feedback regulatory mechanism for CD8+ T cells, but also have strong translational implications in cancer immunotherapy.

immunology↗

bioRxiv2022

Proliferative Exhausted CD8 T Cells Exacerbate Long-lasting Anti-tumor Effects in Human Papillomavirus Positive Head and Neck Squamous Cell Carcinoma

The survival prognosis of human papillomavirus (HPV)-positive and HPV-negative head and neck squamous cell carcinoma (HNSCC) is largely different, and little is known about the anti-tumor mechanism of tumor-infiltrated CD8+ exhausted T cells (Tex) in HNSCC. We performed cell level multi-omics sequencing on human HNSCC samples to decipher the multi-dimensional characteristics of Tex cells. A proliferative exhausted CD8+ T cell cluster (P-Tex) which was beneficial to survival outcomes of patients with HPV-positive HNSCC was identified. Interestingly, P-Tex cells expressed CDK4 genes as high as cancer cells, which could be simultaneously inhibited by CDK4 inhibitors and might be a potential reason for the ineffectiveness of CDK4 inhibitors in treating HPV-positive HNSCC. P-Tex cells could aggregate in the antigen presenting cell niches and activate certain signaling pathways. Together, our findings suggest a promising role for P-Tex cells in the prognosis of patients with HPV-positive HNSCC by providing modest but persistent anti-tumor effects. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/513993v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@1f8810forg.highwire.dtl.DTLVardef@1e11d84org.highwire.dtl.DTLVardef@58fb6aorg.highwire.dtl.DTLVardef@1e20a13_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2022

vamos: VNTR annotation using efficient motif sets

MotivationRoughly 3% of the human genome is composed of variable-number tandem repeats (VNTRs): tandemly repeated arrays of motifs at least six bases. These loci are highly polymorphic: over 61% of insertion and deletion variants at least 50 bases found from long-read assemblies are inside VNTRs. Furthermore, long-read assemblies reveal that VNTR loci are multiallelic, and can vary by both motif composition and copy number. Current approaches that define and merge variants based on alignment breakpoints do not capture this complexity of variation. A natural alternative approach is to instead define the motif composition of VNTR sequences from samples, and to detect differences based on comparisons of repeat composition. However, due to the complexity of VNTR sequences, it is difficult to establish a common reference set of motif sequences that may be used to describe variation in large sequencing studies. ResultsHere we present a method vamos: VNTR Annotation using efficient Motif Sets that for any VNTR locus selects a set of representative motifs from all motifs observed at that locus that may be used to encode VNTR sequences within a bounded edit distance of the original sequence. We use our method to characterize VNTR variation in 32 haplotype-resolved human genomes. In contrast to current studies that merge multi-allelic calls, we estimate an average of 3.1-4.0 alleles per locus. Availabilitygithub.com/chaissonlab/vamos, zenodo.org/record/7158427 Contactmchaisso@usc.edu

bioinformatics↗

bioRxiv2022

Spatially Resolved Single-cell Translatomics at Molecular Resolution

The precise control of mRNA translation is a crucial step in post-transcriptional gene regulation of cellular physiology. However, it remains a major challenge to systematically study mRNA translation at the transcriptomic scale with spatial and single-cell resolutions. Here, we report the development of RIBOmap, a three-dimensional (3D) in situ profiling method to detect mRNA translation for thousands of genes simultaneously in intact cells and tissues. By applying RIBOmap to 981 genes in HeLa cells, we revealed remarkable dependency of translation on cell-cycle stages and subcellular localization. Furthermore, we profiled single-cell translatomes of 5,413 genes in the adult mouse brain tissue with a spatial cell atlas of 62,753 cells. This spatial translatome profiling detected widespread patterns of localized translation in neuronal and glial cells in intact brain tissue networks. Together, RIBOmap presents the first spatially resolved single-cell translatomics technology, accelerating our understanding of protein synthesis in the context of subcellular architecture, cell types, and tissue anatomy.

genomics↗

bioRxiv2022

Spatiotemporally resolved transcriptomics reveals subcellular RNA kinetic landscape

Spatiotemporal regulation of the cellular transcriptome is crucial for proper protein expression and cellular function1. However, the intricate subcellular dynamics of RNA synthesis, decay, export, and translocation remain obscured due to the limitations of existing transcriptomics methods2-8. Here, we report a spatiotemporally resolved RNA mapping method (TEMPOmap) to uncover subcellular RNA profiles across time and space at the single-cell level in heterogeneous cell populations. TEMPOmap integrates pulse-chase metabolic labeling of the transcriptome with highly multiplexed three-dimensional (3D) in situ sequencing to simultaneously profile the age and location of individual RNA molecules. Using TEMPOmap, we constructed the subcellular RNA kinetic landscape of 991 genes in human HeLa cells from upstream transcription to downstream subcellular translocation. Clustering analysis of critical RNA kinetic parameters across single cells revealed kinetic gene clusters whose expression patterns were shaped by multi-step kinetic sculpting. Importantly, these kinetic gene clusters are functionally segregated, suggesting that subcellular RNA kinetics are differentially regulated to serve molecular and cellular functions in cell-cycle dependent manner. Together, these single-cell spatiotemporally resolved transcriptomics measurements provide us the gateway to uncover new gene regulation principles and understand how kinetic strategies enable precise RNA expression in time and space.

genomics↗

bioRxiv2022

Combined blockade of VEGF, Angiopoietin-2, and PD1 reprograms glioblastoma endothelial cells into quasi-antigen-presenting cells

Glioblastoma (GBM) remains a highly aggressive and uniformly fatal tumor, with a 5-year survival of <10%. Moreover, all randomized clinical trials with immune-checkpoint blockers have failed to date. Here we report that tumor endothelial cell (EC) dysfunction confers resistance to immunotherapy in preclinical GBM models. Anti-VEGF-therapy-induced vascular normalization is insufficient to fully restore the EC function and alleviate inflammatory edema induced by blocking programmed cell death protein 1 (PD1). Strikingly, concomitant blockade of angiopoietin 2 (Ang2), vascular endothelial growth factor (VEGF), and programmed cell death protein 1 (PD1) reprograms dysfunctional ECs to quasi-antigen presenting cells and upregulates receptors required for cytotoxic T lymphocyte entry into the tumor. Blocking VEGF, Ang2, and PD1 induces durable anti-tumor response while controlling edema. Upregulation of the transcription factor T-bet is necessary for generating resident memory T cells elicited by this combination therapy. Moreover, a human GBM organoid model formed from human cancer cells, ECs, CD14 and CD8 cells recapitulated these findings. Our study reveals the role of Ang2 in resistance to VEGF and/or PD1-blockade and provides a compelling rationale for clinical evaluation of this combination in GBM patients.

cancer biology↗