Biology subjects

Lyu, J.

Publications and source records attributed to Lyu, J..

68 records · Page 4Linked to original sources

bioRxiv2022

Fertilizer reduction with bio-organic fertilizer to regulate the root soil microbial community structure to improve Baby Chinese cabbage yield

Using high-throughput sequencing, this study aimed to explore the response of soil microbial community and Baby Chinese cabbage yield to the reduction of chemical fertilizers combined with bio-organic fertilizer in the Gansu plateau, China. Our experiments consisted of conventional fertilizer (CK), 30% chemical fertilizer reduction + 6,000 kg bio-organic fertilizer (T1), 30% chemical fertilizer reduction + 9,000 kg bio-organic fertilizer (T2), 40% chemical fertilizer reduction + 6,000 kg bio-organic fertilizer (T3), and 40% chemical fertilizer reduction + 9,000 kg bio-organic fertilizer (T4). Compared with CK, soil microbial diversity and richness were higher for all treatments with added bio-organic fertilizer. PCoA showed that the bacterial and fungal communities in T2 and T4 were similar to each other. Redundancy and Spearmans correlation analyses of microbial communities and soil physicochemical properties revealed that reductions in chemical fertilizer rate combined with bio-organic fertilizer had a stronger impact on the fungal than the bacterial community. They also increased the relative abundance of the dominant bacterial and fungal phyla. Baby Chinese cabbage yield was relatively higher under the combined bio-organic fertilizer plus reduced chemical fertilizer rate with T2 showing the highest yield. Therefore, this approach is feasible for sustainable agricultural, cost-effective and profitable crop production. ImportanceO_LIBio-organic + moderately reduced chemical fertilizer raised Chinese cabbage yield C_LIO_LIBio-organic + chemical fertilizer was more efficacious than either one alone C_LIO_LIPresence of bio-organic fertilizer enhanced overall rhizosphere physicochemistry C_LIO_LIBio-organic fertilizer improved beneficial bacterial & fungal abundance & diversity C_LIO_LIFertilizer combination sustainably & cost-effectively improves crop & soil quality C_LI

microbiology↗

bioRxiv2022

A historically balanced locus under recent directional selection in responding to changed nitrogen conditions during modern maize breeding

Understanding the patterns of selection during plant evolution and recent crop improvement processes is the central topic in plant breeding and genetics. As an essential macronutrient for plant growth and development, nitrogen (N) is a key factor in affecting plant adaptation and crop improvement. The widespread adoption of less expensive industrial N fixation has dramatically reshaped plant morphology by favoring compact maize plants to tolerant crowding stress. The associated genetic changes, however, have not been systematically studied. Here, we investigated maize inbred lines developed before and after the 1960s -- the time point when inorganic N fertilizer started to be widely used for maize production. We identified a strong selective sweep exhibiting pronounced genomic differentiation between Old-Era (pre-1960s) and New-Era (post-1960s) inbred lines. Further study revealed population genetics statistics in the sweep exhibited patterns consistent with historical balancing selection. This balanced genomic interval is associated with a number of morphological, physiological, and metabolite traits related to vegetative N responses. A cluster of three glutamate receptor-like (GLR) genes is located within the region targeted by selection. Functional characterizations suggested differences in transcriptional activity of the GLR genes between the haplotypes carried by Old-Era and New-Era inbred lines likely play an essential role in mediating distinct N responses. The identification of both targets of selection and changes in the regulation of N responsive genes between maize lines developed in different eras sheds light on the N sensing and regulation pathways and paves the way to developing N resilient crops.

genomics↗

bioRxiv2022

An Acyclic Phosphonate Prodrug of HPMPC is Effective Against VZV in Skin Organ Culture and Mice

Varicella zoster virus (VZV) causes chicken pox and shingles and is prevalent worldwide. Acyclovir and penciclovir (and its prodrugs) are first-line treatments for VZV infections, but they are not highly potent against VZV and resistance may arise in immunocompromised people on long-term therapy. HPMPC (cidofovir) is active against VZV, but cidofovir is not approved for treating VZV diseases, is nephrotoxic, and is not orally bioavailable. Here, we present the synthesis and evaluation of USC-373, a phosphonate prodrug of HPMPC with activity against VZV and other DNA viruses. In cultured fibroblasts, it was potent against VZV Ellen laboratory strain and was not overtly toxic, with EC50 of 4 nM and CC50 of 0.20 M, producing a selectivity index of 50. In ARPE-19 cells, USC-373 was effective against VZV-ORF57-Luc wild type strain and the acyclovir-resistant isogenic strain. In human skin organ culture, USC-373 formulated in cocoa butter and applied topically prevented VZV-ORF57-Luc spread without toxicity. In NuSkin mice with human skin xenografts, one daily dose of 3 mg/kg was effective by the subcutaneous route, and one daily dose of 10 mg/kg was effective by the oral route. Remarkably, a 10 mg/kg oral dose given every other day was also effective. USC-373 was well tolerated and mice did not lose weight or show signs of distress. The prodrug modifications of USC-373 increase the potency and oral bioavailability compared to its parent nucleoside analog, HPMPC.

microbiology↗

bioRxiv2022

SARS-CoV-2 Infection of Microglia Elicits Pro-inflammatory Activation and Apoptotic Cell Death

Accumulating evidence suggests that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes various neurological symptoms in coronavirus disease 2019 (COVID-19) patients. The most dominant immune cells in the brain are microglia. Yet, the relationship between neurological manifestations, neuroinflammation, and host immune response of microglia to SARS-CoV-2 has not been well characterized. Here, we report that SARS-CoV-2 can directly infect human microglia, eliciting M1-like pro-inflammatory responses, followed by cytopathic effects. Specifically, SARS-CoV-2 infected human microglial clone 3 (HMC3), leading to inflammatory activation and cell death. RNA-seq analysis also revealed that ER stress and immune responses were induced in the early and apoptotic processes in the late phase of viral infection. SARS-CoV-2-infected HMC3 showed the M1 phenotype and produced pro-inflammatory cytokines such as interleukin (IL)-1{beta}, IL-6, and tumour necrosis factor (TNF-), but not the anti-inflammatory cytokine IL-10. After this pro-inflammatory activation, SARS-CoV-2 infection promoted both intrinsic and extrinsic death receptor-mediated apoptosis in HMC3. Using K18-hACE2 transgenic mice, murine microglia were also infected by intranasal inoculation of SARS-CoV-2. This infection induced the acute production of pro-inflammatory microglial IL-6 and TNF- and provoked a chronic loss of microglia. Our findings suggest that microglia are potential mediators of SARS-CoV-2-induced neurological problems and, consequently, can be targets of therapeutic strategies against neurological diseases in COVID-19 patients. IMPORTANCERecent studies reported neurological manifestations and complications in COVID-19 patients, which are associated with neuroinflammation. As microglia are the dominant immune cells in brains, it needs to be elucidate the relationship between neuroinflammation and host immune response of microglia to SARS-CoV-2. Here, we suggest that SARS-CoV-2 can directly infect human microglia with cytopathic effect (CPE) using human microglial clone 3 (HMC3). The infected microglia were promoted to pro-inflammatory activation following apoptotic cell death. This pro-inflammatory activation was accompanied by the high production of pro-inflammatory cytokines, and led to neurotoxic-M1 phenotype polarization. In vivo, murine microglia were infected and produced pro-inflammatory cytokines and provoked a chronic loss using K18-hACE2 mice. Thus, our data present that SARS-CoV-2-infected microglia are potential mediators of neurological problems in COVID-19 patients. In addition, HMC3 cells are susceptible to SARS-CoV-2 and exhibit the CPE, which can be further used to investigate cellular and molecular mechanisms of neuroinflammation reported in COVID-19 patients.

microbiology↗

bioRxiv2021

Proteomic Characterization of Serum Small Extracellular Vesicles in Human Breast Cancer

There is a lack of comprehensive understanding of breast cancer (BC) specific sEVs characteristics and composition on BC unique proteomic information from human samples. Here, we interrogated the proteomic landscape of sEVs in 167 serum samples from patients with BC, benign mammary disease (BD) and from healthy donors (HD). The analysis provides a comprehensive landscape of serum sEVs with totally 9,589 proteins identified, considerably expanding the panel of sEVs markers. Of note, serum BC-sEVs protein signatures were distinct from those of BD and HD, representing stage- and molecular subtype-specific patterns. We constructed specific sEVs protein identifiers that could serve as a liquid biopsy tool for diagnosis and classification of BC from benign mammary disease, molecular subtypes, as well as assessment of lymph node metastasis. We also identified 11 potential survival biomarkers for distant metastasis. This work may provide reference value for the accurate diagnosis and monitoring of BC progression using serum sEVs.

bioinformatics↗

bioRxiv2021

Crystal structures of the σ2 receptor template large-library docking for selective chemotypes active in vivo

The {sigma}2 receptor is a poorly understood transmembrane receptor that has attracted intense interest in many areas of biology including cancer imaging, Alzheimers disease, schizophrenia, and neuropathic pain. However, little is known regarding the molecular details of the receptor, and few highly selective ligands are available. Here, we report the crystal structure of the {sigma}2 receptor in complex with the clinical drug candidate roluperidone and the probe compound PB28. These structures, in turn, templated a large-scale docking screen of 490 million make-on-demand molecules. Of these, 484 compounds were synthesized and tested, prioritizing not only high-ranking docked molecules, but also those with mediocre and poor scores. Overall, 127 compounds with binding affinities superior to 1 M were identified, all in new chemotypes, 31 of which had affinities superior to 50 nM. Intriguingly, hit rate fell smoothly and monotonically with docking score. Seeking to develop selective and biologically active probe molecules, we optimized three of the original docking hits for potency and for selectivity, achieving affinities in the 3 to 48 nM range and to up to 250-fold selectivity vs. the {sigma}1 receptor. Crystal structures of the newly discovered ligands bound to the {sigma}2 receptor were subsequently determined, confirming the docked poses. To investigate the contribution of the {sigma}2 receptor in pain processing, and to distinguish it from the contribution of the {sigma}1 receptor, two potent {sigma}2-selective and one potent {sigma}1/{sigma}2 non-selective ligand were tested for efficacy in a mouse model of neuropathic pain. All three ligands demonstrated timedependent decreases in mechanical hypersensitivity in the spared nerve injury model, supporting a role for the {sigma}2 receptor in nociception, and a possible role for {sigma}1/{sigma}2 polypharmacology. This study illustrates the opportunities for rapid discovery of in vivo active and selective probes to study under-explored areas of biology using structurebased screens of diverse, ultra-large libraries following the elucidation of protein structures.

pharmacology and toxicology↗

bioRxiv2021

Genome-wide mapping of G-quadruplex structures with CUT&Tag

Single-stranded genomic DNA can fold into G-quadruplex (G4) structures or form DNA:RNA hybrids (R loops). Recent evidence suggests that such non-canonical DNA structures affect gene expression, DNA methylation, replication fork progression and genome stability. When and how G4 structures form and are resolved remains unclear. Here we report the use of Cleavage Under Targets and Tagmentation (CUT&Tag) for mapping native G4 in mammalian cell lines at high resolution and low background. Mild native conditions used for the procedure retain more G4 structures and provide a higher signal-to-noise ratio than ChIP-based methods. We determine the G4 landscape of mouse embryonic stem cells (mESC), observing widespread G4 formation at active promoters, active and poised enhancers. We discover that the presence of G4 motifs and G4 structures distinguishes active and primed enhancers in mESCs. Further, performing R-loop CUT&Tag, we demonstrate the genome-wide co-occurence of single-stranded DNA, G4s and R loops, suggesting an intricate relationship between transcription and non-canonical DNA structures.

genomics↗

bioRxiv2021

Phospholipidosis is a shared mechanism underlying the in vitro antiviral activity of many repurposed drugs against SARS-CoV-2

Repurposing drugs as treatments for COVID-19 has drawn much attention. A common strategy has been to screen for established drugs, typically developed for other indications, that are antiviral in cells or organisms. Intriguingly, most of the drugs that have emerged from these campaigns, though diverse in structure, share a common physical property: cationic amphiphilicity. Provoked by the similarity of these repurposed drugs to those inducing phospholipidosis, a well-known drug side effect, we investigated phospholipidosis as a mechanism for antiviral activity. We tested 23 cationic amphiphilic drugs--including those from phenotypic screens and others that we ourselves had found--for induction of phospholipidosis in cell culture. We found that most of the repurposed drugs, which included hydroxychloroquine, azithromycin, amiodarone, and four others that have already progressed to clinical trials, induced phospholipidosis in the same concentration range as their antiviral activity; indeed, there was a strong monotonic correlation between antiviral efficacy and the magnitude of the phospholipidosis. Conversely, drugs active against the same targets that did not induce phospholipidosis were not antiviral. Phospholipidosis depends on the gross physical properties of drugs, and does not reflect specific target-based activities, rather it may be considered a confound in early drug discovery. Understanding its role in infection, and detecting its effects rapidly, will allow the community to better distinguish between drugs and lead compounds that more directly impact COVID-19 from the large proportion of molecules that manifest this confounding effect, saving much time, effort and cost. One Sentence SummaryDrug-induced phospholipidosis is a single mechanism that may explain the in vitro efficacy of a wide-variety of therapeutics repurposed for COVID-19.

pharmacology and toxicology↗

bioRxiv2020

Viruses of the Thermotogota; the vehicles on the highways of gene sharing.

Phylogenomic analyses of bacteria from the phylum Thermotogota have shown extensive lateral gene transfer (LGT) with distantly related organisms, particularly with Firmicutes. One likely mechanism of such DNA transfer is viruses. However, to date only three temperate viruses have been characterized in this phylum, all infecting bacteria from the Marinitoga genus. Here we report 17 proviruses integrated into genomes of eight Thermotogota genera and induce viral particle production from one of the proviruses. The proviruses fall into two groups based on sequence similarity, gene synteny and taxonomic classification. Proviruses of one group are found in six genera and are similar to the previously identified Marinitoga viruses, while proviruses from the second group are only distantly related to the proviruses of the first group, have different genome organization and are found in only two genera. Both groups are closely related to Firmicutes in genomic and phylogenetic analyses, and one of the groups show evidence of very recent LGT and are therefore likely capable of infecting cells from both phyla. We conjecture that viruses are responsible for a large portion of the observed gene flow between Firmicutes and Thermotogota.

evolutionary biology↗

bioRxiv2020

An ABA Synthesis Enzyme Allele OsNCED2 Promotes the Aerobic Adaption in Upland Rice

There are two ecotypes, upland rice and irrigate rice, during its evolution in rice. Upland rice exhibits aerobic adaptive phenotype via its stronger root system and more rapid drought responses compared with its counterpart, irrigated rice. We assessed the functional variation and applications of the aerobic adaptive allele OsNCED2T cloned from IRAT104 which is a cultivar of upland rice. OsNCED2-overexpressing transgenic rice and OsNCED2T-NILs exhibited significantly higher ABA contents at the seedling and reproductive stages, which can improve root development (RD) and drought tolerance (DT) to promote aerobic adaptation in upland rice. RNA-Seq-based expression profiling of transgenic versus wild-type rice identified OsNCED2-mediated pathways that regulate RD and DT. Meanwhile, OsNCED2-overexpressing rice exhibited significantly increased reactive oxygen species (ROS)-scavenging abilities and transcription levels of many stress- and development-related genes, which regulate RD and DT. A SNP mutation (C to T) from irrigated rice to upland rice, caused the functional variation of OsNCED2, and the enhanced RD and DT mediated by this site under aerobic conditions could promote higher yield of upland rice. These results show that OsNCED2T, through ABA synthesis, positively modulates RD and DT which confers aerobic adaptation in upland rice and might serve as a novel gene for breeding aerobic adaptive or water-saving rice.

plant biology↗

bioRxiv2020

Adaptive evolution of DNA methylation reshaped gene regulation in maize

DNA methylation is a ubiquitous chromatin feature -- in maize, more than 25% of cytosines in the genome are methylated. Recently, major progress has been made in describing the molecular mechanisms driving methylation, yet variation and evolution of the methylation landscape during maize domestication remain largely unknown. Here we leveraged whole-genome sequencing (WGS) and whole genome bisulfite sequencing (WGBS) on populations of modern maize, landrace, and teosinte (Zea mays ssp. parviglumis) to investigate the adaptive and phenotypic consequences of methylation variations in maize. By using a novel estimation approach, we inferred the methylome site frequency spectrum (mSFS) to estimate forward and backward epimutation rates and selection coefficients. We found weak evidence for direct selection on DNA methylation in any context, but thousands of differentially methylated regions (DMRs) were identified in population-wide that are correlated with recent selection. Further investigation revealed that DMRs are enriched in 5 untranslated regions, and that maize hypomethylated DMRs likely helped rewire distal gene regulation. For two trait-associated DMRs, vgt1-DMR and tb1-DMR, our HiChIP data indicated that the interactive loops between DMRs and respective downstream genes were present in B73, a modern maize line, but absent in teosinte. Functional analyses suggested that these DMRs likely served as cis-acting elements that modulated gene regulation after domestication. Our results enable a better understanding of the evolutionary forces acting on patterns of DNA methylation and suggest a role of methylation variation in adaptive evolution.

plant biology↗

bioRxiv2019

MATRIEX Imaging: Multi-Area Two-photon Real-time In-vivo Explorer

Two-photon laser scanning microscopy, originally developed since 1990s1, has been widely applied for biomedical research in recent decades, particularly popular among neuroscientists for studying neural functions in vivo2. However, it is typically restricted to one imaging area that is orthogonal to the optical axis. Here, we demonstrate a novel multi-axis optical conjugation method that enables two-photon imaging at single-cell resolution simultaneously in multiple areas at different depths, each of which could have a view diameter of ~200 m and could be largely freely targeted within a zone up to 12-mm diameter. For example, we show simultaneous imaging of neuronal activities in the primary visual cortex (V1), the primary motor cortex (M1) and the hippocampal CA1 region of awake mice. This method can be readily implemented on a single conventional two-photon microscope to enable multi-area exploration of neuronal activities in vivo.

neuroscience↗

bioRxiv2018

Development and Validation of a Method for Human Papillomavirus Genotyping Based on Molecular Beacon Probes

We describe a new assay system for the genotyping of human papillomavirus (HPV) based on linear-after-the-exponential-PCR and melting curve analysis. This system can detect and identify the 23 most common HPV strains (types 6, 11, 16, 18, 31, 33, 35, 39,42, 45, 51, 52, 53, 56, 58, 59, 66, 68, 70, 73, 81, 82, and 83) in two sealed reaction tubes within 2 h. The sensitivity and specificity of this new system was validated using cloned HPV DNA and clinical samples. The detection limit was 5-500 copies/reaction depending on the genotype, and no cross-reactivity was observed with any other low-risk HPV or pathogen that was commonly found in the female genital tract. When compared with the HPV GenoArray test kit, the testing of 1104 clinical samples produced a good overall agreement between the two methods of 98.37% (95% CI: 97.44%-98.97%) and a kappa value of 0.954. Thus, this new HPV genotyping assay system represents a simple, rapid, universally applicable, sensitive, and highly specific detection methodology that should be useful for cervical lesion screening and, thus, is potentially of great value in future clinical applications.

molecular biology↗

bioRxiv2018

Reactive Initiation Training is more effective than Shuttle Run to improve the on-court agility of novice badminton players

PurposeDespite its well-known importance in sports, agility is ambiguously defined and lack of research. Shuttle Run (SR) is commonly used to improve the on-court agility of badminton players. Reactive Initiation Training (RIT) contrasts SR in that it only demands rapid generation of initiation step toward the direction of shuttlecock. The current study compared SR with RIT to determine which one is more effective for improving on-court agility of novice badminton players.\n\nMethod20 novice badminton players were split in half to receive either RIT or SR on court for five days. Before and after training, participants were assessed on their ability to intercept the shuttlecocks randomly thrown by a coach to six corners of the court with and without visual occlusion of the coach. All trials of interception were recorded for video analysis of initiation time, running time and total time.\n\nResultsThe mean total times were greater with visual occlusion and varied systematically with the position of interception. Both training methods shortened the mean running time, however, only RIT additionally reduced the initiation time and its proportion on those time-consuming positions in the occluded condition.\n\nConclusionRIT is more effective than SR to improve the on-court agility of novice badminton players.

physiology↗