Biology subjects

Yin, H.

Publications and source records attributed to Yin, H..

At least 73 records · Page 4Linked to original sources

bioRxiv2024

Discovery and Repurposing of Pharmaceutical Agents as Antifungals: In vivo activity against Coccidioides

There is significant interest in identifying improved treatments for coccidioidomycosis, an endemic fungal infection found in the southwestern United States, and Central and South America. The current standard of care, fluconazole, often fails to completely eradicate Coccidioides infection; however, the cost of identifying new compounds is often high in terms of both finances and time. Therefore, repurposing existing pharmaceutical agents is an attractive option. In our previous work, we identified several compounds which inhibited fungal growth in vitro. Based on these findings, we screened a subset of these agents to increase the performance of fluconazole in a combination therapy approach, as compared to fluconazole alone, in a murine model. We observed that combination therapy of sertraline:fluconazole significantly reduced the amount of live fungus in the lung compared to fluconazole alone. These results suggest that sertraline can be repurposed as an adjunctive agent in the treatment of this important fungal disease.

microbiology↗

bioRxiv2024

Skeletal muscle effects of antisense oligonucleotides targeting glycogen synthase 1 in a mouse model of Pompe disease

Pompe disease (PD) is a progressive myopathy caused by the aberrant accumulation of glycogen in skeletal and cardiac muscle resulting from the deficiency of the enzyme acid alpha-glucosidase (GAA). Administration of recombinant human GAA as enzyme replacement therapy (ERT) works well in alleviating the cardiac manifestations of PD but loses sustained benefit in ameliorating the skeletal muscle pathology. The limited efficacy of ERT in skeletal muscle is partially attributable to its inability to curb the accumulation of new glycogen produced by the muscle enzyme glycogen synthase 1 (GYS1). Substrate reduction therapies aimed at knocking down GYS1 expression represent a promising avenue to improve Pompe myopathy. However, finding specific inhibitors for GYS1 is challenging given the presence of the highly homologous GYS2 in the liver. Antisense oligonucleotides (ASOs) are chemically modified oligomers that hybridize to their complementary target RNA to induce their degradation with exquisite specificity. In the present study, we show that ASO-mediated Gys1 knockdown in the Gaa-/- mouse model of PD led to a robust reduction in glycogen accumulation in skeletal and cardiac muscle. In addition, combining Gys1 ASO with ERT further reduced glycogen content in muscle, eliminated autophagic buildup and lysosomal dysfunction, and improved motor function in Gaa-/- mice. Our results provide a strong foundation for further validation of the use of Gys1 ASO, alone or in combination with ERT, as a therapy for PD. We propose that early administration of Gys1 ASO in combination with ERT may be the key to preventative treatment options in PD.

molecular biology↗

bioRxiv2024

The Origin and Evolution of Orphan Genes: A Case Study in Tea Plant Family

Orphan genes and transcription factor genes (TFs) are pervasive across genomes, play pivotal roles as regulators in a myriad of biological processes. Despite their ubiquity, the evolutionary trajectories and functional divergence of these genes remain largely unexplored. Theaceae family, encompassing the economically and culturally significant tea plant, presents a unique opportunity to study these dynamics. Here, we decoded a nearly complete, chromosome-scale reference genome of Stewartia gemmata spanning 2.95 Gb. This study is enhanced by integrating the genome of S. gemmata, an early-diverging species within Theaceae, crucial for phylogenomic analyses and understanding the functional dynamics of orphan genes in this family. Our analysis confirmed the absence of a recent specific whole-genome duplication (WGD) event, with tandem duplications emerging as the predominant mechanism for gene duplication at ancestral nodes within Theaceae. By conducting an extensive comparative genomics analysis across 13 Theaceae and comparing these with a wide array of eukaryotic and prokaryotic proteins, we identified 37,618 orphan genes and 25,884 TFs in Theaceae. Interestingly, some orphan genes appear to have ancient origins in tea plant ancestors, suggesting relatively early origins with frequent gains and losses, conversely, many others seem more specific and recent. Notably, the orphan genes are characterized by shorter lengths, fewer exons and functional domains than TFs, implying relatively simpler functional roles. These orphan genes demonstrate diverse cellular localization and functions as predicted by GO/KEGG analysis, and are implicated in environmental response and flavor formation in tea plants. This study not only sheds light on the distinct evolutionary histories and functional divergences between orphan genes and TFs in Theaceae, but also contributes to our understanding of the genetic complexity and adaptability of this economically and culturally valuable plant family. Short summary: The nearly complete genome of an early-diverging species Stewartia gemmata and phylogenomic studies provide insights into new gene evolution in Theaceae.

bioinformatics↗

bioRxiv2023

Exploratory study of pulsed electric field ablation on atherosclerotic plaque in a rabbit model

New understanding of the pathogenesis of atherosclerotic diseases has led to the emergence of new therapeutic approaches. We explored the potential therapeutic effects of pulsed field potential ablation (PFA), a non-thermal ablation technique with high tissue selectivity, on atherosclerotic plaques. Carotid arteries of 30 high-fat rabbits were dilated with a balloon to obtain atherosclerotic plaques. PFA was administered on the carotid atherosclerotic plaques with 1000V/cm, 2000V/cm, and 1000V/cm ablation followed by rapamycin infusion. There were no visible changes in blood vessels after acute ablation, but apoptosis and polarity of cells were observed in atherosclerotic plaques. At 7 and 30 days after ablation, the density of lipid deposition in the plaque was significantly reduced, and multiple layers of new arranged anterograde smooth muscle cells appeared, replacing the original atherosclerotic plaque. The residual atherosclerotic structure is sandwiched between the new smooth muscle layer and the original smooth muscle layer, which makes vascular wall thicker and makes vascular wall elasticity increased. Rapamycin delays the vascular remodeling process. Conclusion: PFA ablation can reduce lipid deposition in atherosclerotic plaques, cause vascular remodeling, and enhance vascular elasticity. We believe that it may be a potential method for the treatment of atherosclerotic plaques.

biophysics↗

bioRxiv2023

Structural basis for the concerted antiphage activity in the SIR2-HerA system

Recently, a novel two-gene bacterial defense system against phages, encoding a SIR2 NADase and a HerA translocase, has been identified. However, the molecular mechanism of the bacterial SIR2-HerA immune system remains unclear. Here, we determine the cryo-EM structures of SIR2, HerA and their complex in different functional states. The SIR2 proteins oligomerize into a dodecameric ring-shaped structure consisting of two layers of interlocked hexamers, in which each SIR2 unit exhibits an auto-inhibited conformation. Distinct from the canonical AAA+ proteins, the HerA hexamer in this antiphage system adopts a split spiral arrangement, resembling the substrate-binding state, which is stabilized by a unique C-terminal extension. SIR2 and HerA proteins assemble into a [~] 1.1 MDa torch-shaped complex to fight against phage infection. Importantly, disruption of the interactions between SIR2 and HerA largely abolishes the antiphage activity. Interestingly, HerA binding alters the oligomer state of SIR2, switching from a 12-mer state to a 14-mer state. On the other hand, binding of SIR2 stimulates the ATPase activity of HerA. Together, our study not only provides a structural basis for the functional communications between SIR2 and HerA proteins, but also unravels a novel concerted antiviral mechanism through nucleotide (NAD+ and ATP) depletion.

biochemistry↗

bioRxiv2023

Targeted Deletion of All Known Thyroid Hormone Receptors Causes Maturation Retardation and Early-onset Degeneration of Cochlear Outer Sulcus

Thyroid hormone (TH) and its receptors (TRs) are crucial for cochlear late-stage development and endocochlear potential (EP) maintenance. However, the mechanism underlying EP reduction in the absence of TH or TRs remains elusive. Cochlear outer sulcus root cells undergo significant morphological changes during late-stage cochlear development and are believed to play a role in maintaining endolymph homeostasis and EP. Yet, it is unknown whether TH and/or TRs are necessary for root cell differentiation and function. Here, we elucidate the essential role of TH or TRs in postnatal root cell development and survival in mice. TH deficiency significantly delayed root cell differentiation. Otocyst-selective deletion of both Thra and Thrb, but not Thrb alone, leads to a similar impairment, accompanied by early degeneration of root cells, with the stria vascularis remaining unaffected. Furthermore, a 22% reduction in mean EP magnitudes was observed in conditional TRs double knockout mice at 4 months of age, less pronounced than in global TRs knockout mice. Transcriptome analysis reveals that TH deficiency downregulates a significant portion of root cell-enriched genes. These findings underscore the redundant roles of TR and TR{beta} in promoting the late-stage differentiation and survival of root cells. Additionally, they suggest that the expression of TRs in cochlear epithelium is crucial for maintaining an optimal EP magnitude, while TRs expressed in areas outside cochlear epithelium, particularly in spiral ligament fibrocytes, may also significantly contribute to EP maintenance. This study advances our understanding of TH in cochlear outer sulcus development and EP maintenance.

developmental biology↗

bioRxiv2023

Integrating large-scale meta-GWAS and PigGTEx resources to decipher the genetic basis of complex traits in pig.

Understanding the molecular and cellular mechanisms that underlie complex traits in pigs is crucial for enhancing their genetic improvement program and unleashing their substantial potentials in human biomedicine research. Here, we conducted a meta-GWAS analysis for 232 complex traits with 28.3 million imputed whole-genome sequence variants in 70,328 individuals from 14 pig breeds. We identified a total of 6,878 genomic regions associated with 139 complex traits. By integrating with the Pig Genotype-Tissue Expression (PigGTEx) resource, we systemically explored the biological context and regulatory circuits through which these trait-associated variants act and finally prioritized 16,664 variant-gene-tissue-trait circuits. For instance, rs344053754 regulates the expression of UGT2B31 in the liver by affecting the activity of regulatory elements and ultimately influences litter weight at weaning. Furthermore, we investigated the conservation of genetic and regulatory mechanisms underlying 136 human traits and 232 pig traits. Overall, our multi-breed meta-GWAS in pigs provides invaluable resources and novel insights for understanding the regulatory and evolutionary mechanisms of complex traits in both pigs and humans.

genetics↗

bioRxiv2023

Attenuating midline thalamus bursting to mitigate absence epilepsy

Advancing the mechanistic understanding of absence epilepsy is crucial for developing new therapeutics, especially for patients unresponsive to current treatments. Utilizing a recently developed mouse model of absence epilepsy carrying the BK gain-of-function channelopathy D434G, here we report that attenuating the burst firing of midline thalamus (MLT) neurons effectively prevents absence seizures. We found that enhanced BK channel activity in the BK-D434G MLT neurons promotes synchronized bursting during the ictal phase of absence seizures. Modulating MLT neurons through pharmacological reagents, optogenetic stimulation, or deep brain stimulation effectively attenuates burst firing, leading to reduced absence seizure frequency and increased vigilance. Additionally, enhancing vigilance by amphetamine, a stimulant medication, or physical perturbation also effectively suppresses MLT bursting and prevents absence seizures. These findings suggest that the MLT is a promising target for clinical interventions. Our diverse approaches offer valuable insights for developing new therapeutics to treat absence epilepsy. HighlightsThe midline thalamus (MLT) is a key thalamic region for absence seizure pathogenesis MLT neurons exhibit synchronized bursting during ictal phase. BK channel contributes to MLT burst firing Attenuating MLT bursting increases vigilance and suppresses absence seizures

neuroscience↗

bioRxiv2023

Muscarinic Signaling Pathway Controls Cortical Circuit Regulation of Lateral Ventricle Quiescent Neural Stem Cells

Neurogenesis and proliferation of neural stem cells (NSCs) in the subventricular zone (SVZ) are controlled by both intrinsic molecular pathways and extrinsic signaling cues, including neural circuits. One such circuit, the ACC-subep-ChAT+ circuit, has been identified as a regulator of ventral SVZ neurogenesis by modulating the proliferation of LV NSCs. However, the specific neural signals that promote the proliferation activity of LV NSCs have remained largely unknown. In this study, we uncover a molecular mechanism underlying the cellular activation and proliferation of quiescent NSCs (qNSCs) in the lateral ventricle SVZ (LV-SVZ) mediated by the cortical circuit. Our findings demonstrate that postnatal and adult LV qNSCs are triggered by the cortical circuit through ChAT+ neuron stimulation, consequently resulting in the activation of muscarinic 3 receptors (M3) expressed on LV qNSCs. This, in turn, triggers inositol 1,4,5-trisphosphate receptor type 1 (IP3R1) activation, causing intracellular calcium release. Subsequently, the proliferation of LV qNSCs occurs through the downstream regulation of the calcium/calmodulin dependent protein kinase II delta (CAMK2D) and the MAPK10 signaling pathway. These findings shed light on the molecular regulatory mechanisms that govern LV qNSCs and emphasize the significant role of the cortical circuit in promoting their proliferative activation within the ventral LV-SVZ.

cell biology↗

bioRxiv2023

Dual α-globin and truncated erythropoietin receptor knock-in restores hemoglobin production in α-thalassemia major-derived hematopoietic stem and progenitor cells

Alpha-thalassemia is an autosomal recessive disease with increasing worldwide prevalence. The molecular basis is due to mutation or deletion of one or more duplicated -globin genes, and disease severity is directly related to the number of allelic copies compromised. The most severe form, -thalassemia major (TM), results from loss of all four copies of -globin and has historically resulted in fatality in utero. However, in utero transfusions now enable survival to birth. Postnatally, patients face challenges similar to {beta}-thalassemia, including severe anemia and erythrotoxicity due to imbalance of {beta}-globin and -globin chains. While curative, hematopoietic stem cell transplantation (HSCT) is limited by donor availability and potential transplant-related complications. Despite progress in genome editing treatments for {beta}-thalassemia, there is no analogous curative option for patients suffering from -thalassemia. To address this, we designed a novel Cas9/AAV6-mediated genome editing strategy that integrates a functional -globin gene into the {beta}-globin locus in TM patient-derived hematopoietic stem and progenitor cells (HSPCs). Incorporation of a truncated erythropoietin receptor transgene into the -globin integration cassette dramatically increased erythropoietic output from edited HSPCs and led to the most robust production of -globin, and consequently normal hemoglobin. By directing edited HSPCs toward increased production of clinically relevant RBCs instead of other divergent cell types, this approach has the potential to mitigate the limitations of traditional HSCT for the hemoglobinopathies, including low genome editing and low engraftment rates. These findings support development of a definitive ex vivo autologous genome editing strategy that may be curative for -thalassemia. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=177 SRC="FIGDIR/small/555926v2_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@1b63dacorg.highwire.dtl.DTLVardef@18b25a1org.highwire.dtl.DTLVardef@53835corg.highwire.dtl.DTLVardef@d52bf5_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

bioRxiv2023

Chromosome-Level Genome Assembly of Navel orange cv. Gannanzao (Citrus sinensis Osbeck cv. Gannanzao)

Navel orange cv. Gannanzao is a variant of the navel orange cv. Newhall (C. sinensis Osbeck cv. Newhall) that exhibits an earlier maturation, making it commercially valuable. However, the underlying mechanism underneath its early maturation remains unknown. To address this question, we conducted genome sequencing and de novo assembly of navel orange cv. Gannanzao. The assembled genome sequence is 334.57 Mb in length with a GC content of 31.48%. It comprises 318 contigs (N50 = 3.23 Mb) and 187 scaffolds (N50 = 31.86 Mb). The BUSCO test demonstrates 94.6% completeness. The annotation revealed 23,037 gene models, 164.95 Mb of repetitive sequences, and 2,554 ncRNA. Comparative analysis identified 323 fruit ripening-related genes in navel orange cv. Gannanzao genome, while navel orange cv. Newhall genome contained 345 such genes. These genes were organized into 320 orthologous gene families, with 30.3% of them exhibiting differences in gene copy numbers between the two genomes. Additionally, we identified 15 fruit ripening-related genes that have undergone adaptive evolution, suggesting their potential role in advancing fruit maturation in navel orange cv. Gannanzao. Whole genome sequencing and annotation of navel orange cv. Gannanzao provides a valuable resource to unravel the early maturation mechanism of citrus and enriches the genomic resources for citrus research.

genomics↗

bioRxiv2023

Chromosome-Level Genome Assembly of Navel orange cv. Gannanzao (Citrus sinensis Osbeck cv. Gannanzao)

genomics↗

bioRxiv2023

Recombinant Ranpirnase enhances the expression of co-transfected mRNA by modulating cellular metabolic activity

As the worlds first approved prophylactic mRNA vaccine, the development of the Covid-19 mRNA vaccine marks a milestone in mRNA therapeutics. However, achieving efficient transgene expression in therapeutic applications such as protein replacement and cancer therapeutical vaccines remains challenging. This study explores the use of recombinant Ranpirnase, a small ribonuclease, as a novel expression-enhancing tool for mRNA-based therapeutics. In Balb/c mice, co-expression of Ranpirnase significantly increased transgene expression levels by 3-to 6-fold and prolonged expression duration by more than 85%, regardless of mRNA nucleoside modification status. Recombinant Ranpirnase induces a cytostatic state in host cells, stabilizing mRNA and protein transcripts, thereby enhancing transgene expression. Importantly, co-expression of Ranpirnase recombinants did not cause detectable cytotoxicity or alter the tissue distribution of transgene expression, ensuring safety and tolerability at higher translation levels. The compact size of the recombinant Ranpirnase gene allows for seamless fusion with the target gene or co-transfection with existing delivery technologies. Altogether, recombinant Ranpirnase shows promise as an expression-enhancing element in mRNA-based therapeutics, including veterinary applications.

molecular biology↗

bioRxiv2023

SPIN-CGNN: Improved fixed backbone protein design with contact map-based graph construction and contact graph neural network

Recent advances in deep learning have significantly improved the ability to infer protein sequences directly from protein structures for the fix-backbone design. The methods have evolved from the early use of multi-layer perceptrons to convolutional neural networks, transformer, and graph neural networks (GNN). However, the conventional approach of constructing K-nearest-neighbors (KNN) graph for GNN has limited the utilization of edge information, which plays a critical role in network performance. Here we introduced SPIN-CGNN based on protein contact maps for nearest neighbors. Together with auxiliary edge updates and selective kernels, we found that SPIN-CGNN provided a comparable performance in refolding ability by AlphaFold2 to the current state-of-the-art techniques but a significant improvement over them in term of sequence recovery, perplexity, deviation from amino-acid compositions of native sequences, conservation of hydrophobic positions, and low complexity regions, according to the test by unseen structures and "hallucinated" structures. Results suggest that low complexity regions in the sequences designed by deep learning techniques remain to be improved, when compared to the native sequences.

bioinformatics↗

bioRxiv2023

Time is of the essence: A novel framework for uncovering temporal structures of communities

Ecological communities are inherently dynamic: species constantly turn over within years, months, weeks, or even days. These temporal shifts in community composition determine essential aspects of species interactions and how energy, nutrients, information, diseases, and perturbations "flow" through systems. Yet, our understanding of community structure has relied heavily on static analyses not designed to capture critical features of this dynamic temporal dimension of communities. Here, we propose a conceptual and methodological framework for quantifying and analyzing this temporal dimension. Conceptually, we split the temporal structure into two definitive features, sequence and duration, and review how they are linked to key concepts in ecology. We then outline how we can capture these definitive features using perspectives and tools from temporal graph theory. We demonstrate how we can easily integrate ongoing research on phenology into this framework and highlight what new opportunities arise from this approach to answer fundamental questions in community ecology. As climate change reshuffles ecological communities worldwide, quantifying the temporal organization of communities is imperative to resolve the fundamental processes that shape natural ecosystems and predict how these systems may change in the future.

ecology↗

bioRxiv2023

The ChickenGTEx pilot analysis: a reference of regulatory variants across 28 chicken tissues

Chicken is a valuable model for understanding fundamental biology, vertebrate evolution and diseases, as well as a major source of nutrient-dense and lean-protein-enriched food globally. Although it is the first non-mammalian amniote genome to be sequenced, the chicken genome still lacks a systematic characterization of functional impacts of genetic variants. Here, through integrating 7,015 RNA-Seq and 2,869 whole-genome sequence data, the Chicken Genotype- Tissue Expression (ChickenGTEx) project presents the pilot reference of regulatory variants in 28 chicken tissue transcriptomes, including millions of regulatory effects on primary expression (including protein-coding genes, lncRNA and exon) and post-transcriptional modifications (alternative splicing and 3 untranslated region alternative polyadenylation). We explored the tissue-sharing and context-specificity of these regulatory variants, their underlying molecular mechanisms of action, and their utility in interpreting adaptation and genome-wide associations of 108 chicken complex traits. Finally, we illustrated shared and lineage-specific features of gene regulation between chickens and mammals, and demonstrated how the ChickenGTEx resource can further assist with translating genetic findings across species. One-Sentence SummaryThe ChickenGTEx provides a multi-tissue reference of regulatory variants for chicken genetics and genomics, functional genomics, precision breeding, veterinary medicine, vertebrate evolution and even human biomedicine.

genetics↗

bioRxiv2023

IPEV: Identification of Prokaryotic and Ekaryotic Vrus-derived sequences in virome using deep learning

BackgroundThe virome obtained through virus-like particle enrichment contain a mixture of prokaryotic and eukaryotic virus-derived fragments. Accurate identification and classification of these elements are crucial for understanding their roles and functions in microbial communities. However, the rapid mutation rates of viral genomes pose challenges in developing high-performance tools for classification, potentially limiting downstream analyses. FindingsWe present IPEV, a novel method that combines trinucleotide pair relative distance and frequency with a 2D convolutional neural network for distinguishing prokaryotic and eukaryotic viruses in viromes. Cross-validation assessments of IPEV demonstrate its state-of-the-art precision, significantly improving the F1-score by approximately 22% on an independent test set compared to existing methods when query viruses share less than 30% sequence similarity with known viruses. Furthermore, IPEV outperforms other methods in terms of accuracy on most real virome samples when using sequence alignments as annotations. Notably, IPEV reduces runtime by 50 times compared to existing methods under the same computing configuration. We utilized IPEV to reanalyze longitudinal samples and found that the gut virome exhibits a higher degree of temporal stability than previously observed in persistent personal viromes, providing novel insights into the resilience of the gut virome in individuals. ConclusionsIPEV is a high-performance, user-friendly tool that assists biologists in identifying and classifying prokaryotic and eukaryotic viruses within viromes. The tool is available at https://github.com/basehc/IPEV.

bioinformatics↗

bioRxiv2023

Force tuning explains changes in phasic dopamine signaling during stimulus-reward learning

According to a popular hypothesis, phasic dopamine (DA) activity encodes a reward prediction error (RPE) necessary for reinforcement learning. However, recent work showed that DA neurons are necessary for performance rather than learning. One limitation of previous work on phasic DA signaling and RPE is the limited behavioral measures. Here, we measured subtle force exertion while recording and manipulating DA activity in the ventral tegmental area (VTA) during stimulus-reward learning. We found two major populations of DA neurons that increased firing before forward and backward force exertion. Force tuning is the same regardless of learning, reward predictability, or outcome valence. Changes in the pattern of force exertion can explain results traditionally used to support the RPE hypothesis, such as modulation by reward magnitude, probability, and unpredicted reward delivery or omission. Thus VTA DA neurons are not used to signal RPE but to regulate force exertion during motivated behavior.

neuroscience↗