bioRxiv Science⌕ Search

Biology subjects

Xia, Y.

Publications and source records attributed to Xia, Y..

At least 199 records · Page 11Linked to original sources

Sphingosine 1-phosphate activates the MAP3K1-JNK pathway to promote epithelial movement and morphogenesis

MAP 3 kinase 1 (MAP3K1) plays an essential role in embryonic eyelid development. It regulates epithelial morphogenesis through the spatial-temporal activation of Jun N-terminal kinases (JNKs), resulting in forward progression of the embryonic eyelid epithelial cells to enable eyelid closure. The developmental signals that activate the MAP3K1-JNK pathway are still unknown, mainly due to the lack of suitable keratinocyte lines to elucidate the mechanisms of pathway regulation. To address this deficiency, we developed a straightforward method for long-term culture of mouse keratinocytes in feeder-free conditions using Ca2+-free media. Cells grown under these conditions displayed characteristic basal epithelial morphology and keratin 14 expression, but did not form tight- or adherens-junctions. Increased extracellular Ca2+ levels restored the formation of cell-cell junctions. Using keratinocyte lines derived from wild type and Map3k1-deficient mice, we found that sphingosine 1-phosphate (S1P) activated the JNK-c-JUN pathways in a manner dependent on MAP3K1 kinase activity and that this MAP3K1-mediated signaling led to epithelial cell migration. The in vivo roles of this pathway were examined through crossing of genetic mutant mice. Loss-of-function of the S1P receptor (S1pr) 2/3 became haploinsufficient only when combined with Map3k1 and Jnk1 mutations such that the compound mutants displayed eyelid closure defects, suggesting these gene products cooperated in eye morphogenesis. Results of this work establish the S1PR-MAP3K1-JNK pathway as a crucial signaling mechanism for epithelial cell movement and morphogenesis.View Full Text

developmental biology↗

HYD3, a conidial hydrophobin of the fungal entomopathogen Metarhizium acridum induces the immunity of its specialist host locust

Conidial hydrophobins in fungal pathogens of plants1,2, insects3,4, and humans5,6 are required for fungal attachment and are associated with high virulence. They are believed to contribute to the pathogenesis of infection by preventing immune recognition5,6. Here, we refute this generalisation offering a more nuanced analysis. We show that MacHYD3, a hydrophobin located on the conidial surface of the specialist entomopathogenic fungus Metarhizium acridum, activates specifically the humoral and cellular immunity of its own host insect, Locusta migratoria manilensis (Meyen) but not that of other non-host insects. When topically applied to the cuticle, purified MacHYD3 improved the resistance of locusts to both specialist and generalist fungal pathogens but had no effect on the fungal resistance of other insects, including Spodoptera frugiperda and Galleria mellonella. Hydrophobins extracted from the generalist fungal pathogens M. anisopliae and Beauveria bassiana had no effect on the resistance of locusts to fungal infection. Thus, the host locust has evolved to recognize the conidial hydrophobin of its specialist fungal pathogen, whereas conidial hydrophobins from generalist fungi are able to evade recognition. Our results distinguish the immunogenic potential of conidial hydrophobins between specialist and generalist fungi.

microbiology↗

Cross-neutralization antibodies against SARS-CoV-2 and RBD mutations from convalescent patient antibody libraries

The emergence of coronavirus disease 2019 (COVID-19) pandemic led to an urgent need to develop therapeutic interventions. Among them, neutralizing antibodies play crucial roles for preventing viral infections and contribute to resolution of infection. Here, we describe the generation of antibody libraries from 17 different COVID-19 recovered patients and screening of neutralizing antibodies to SARS-CoV-2. After 3 rounds of panning, 456 positive phage clones were obtained with high affinity to RBD (receptor binding domain). Then the positive clones were sequenced and reconstituted into whole human IgG for epitope binning assays. After that, all 19 IgG were classified into 6 different epitope groups or Bins. Although all these antibodies were shown to have ability to bind RBD, the antibodies in Bin2 have more superiority to inhibit the interaction between spike protein and angiotensin converting enzyme 2 receptor (ACE2). Most importantly, the antibodies from Bin2 can also strongly bind with mutant RBDs (W463R, R408I, N354D, V367F and N354D/D364Y) derived from SARS-CoV-2 strain with increased infectivity, suggesting the great potential of these antibodies in preventing infection of SARS-CoV-2 and its mutations. Furthermore, these neutralizing antibodies strongly restrict the binding of RBD to hACE2 overexpressed 293T cells. Consistently, these antibodies effectively neutralized pseudovirus entry into hACE2 overexpressed 293T cells. In Vero-E6 cells, these antibodies can even block the entry of live SARS-CoV-2 into cells at only 12.5 nM. These results suggest that these neutralizing human antibodies from the patient-derived antibody libraries have the potential to become therapeutic agents against SARS-CoV-2 and its mutants in this global pandemic.

immunology↗

Risperidone-induced changes in DNA methylation from peripheral blood in first-episode schizophrenia parallel neuroimaging and cognitive phenotype

Today, second generation anti-psychotics such as clozapine and risperidone are the favored treatment for schizophrenia. Yet, the absence of relevant biomarkers that can decode their neurobiological effect shackles our ability to accurately predict and track response to treatment. While researchers have investigated DNA methylation as a biomarker for schizophrenia risk, none have performed a systematic analysis of the effect of antipsychotics upon DNA methylation. We hypothesize that disease-related methylation changes occur before treatment, and that acute antipsychotic treatment may affect DNA methylation. We designed a longitudinal DNA methylation study to estimate risperidones effect on DNA methylation and how changes in DNA methylation might influence risperidones therapeutic effect on behavioral and neuroimaging phenotypes. Thirty-eight patients with first-episode drug-naive schizophrenia (FES) and 38 demographically-matched individuals (healthy controls) participated. We identified brain related pathways enriched in 8,204 FES-associated methylation sites. Risperidone administration altered methylation in 6,143 CpG DNA sites. Post-treatment FES associated with methylation in 6760 CpG sites. Majority of the DNA methylation changes were treatment effect in the overall CpG sites, the FES associated CpG sites, and risperidone associated CpG sites, except for the post-treatment FES associated CpG sites. There were 590 DNA methylation cites normalized by risperidone treatment. The methylation changes of these 590 CpG sites were related to alterations in symptom severity, spontaneous neurophysiological activity, and cognitive function. To our knowledge, this is the first longitudinal methylation study of drug treatment effect and side effect in psychiatric disorders to include parallel studies of neuroimaging and cognitive phenotypes. We identified FES-associated CpG sites not confounded by drug treatment as potential SCZ biomarkers. The normalization effect of risperidone monotherapy suggests that DNA methylation changes may serve as a predictive biomarker for treatment effect. The constructed methylation-phenotype network revealed a relationship between methylation and a wide range of biological and psychological variables.

pharmacology and toxicology↗

Genome-centric portrait of the microbes' cellulolytic competency

Neither the abundance of the exo/endoglucase GH modules nor the taxonomy affiliation is informative enough in inferring whether a genome is of a potential cellulolytic microbe or not. By interpreting the complete genomes of 2642 microbe strains whose phenotypes have been well documented, we are trying to reveal a more reliable genotype and phenotype correlation on the specific function niche of cellulose hydrolysis. By incorporating into the annotation approach an automatic recognition of the potential synergy machineries, a more reliable prediction on the corresponding microbes cellulolytic competency could be achieved. The potential cellulose hydrolyzing microbes could be categorized into 5 groups according to the varying synergy machineries among the carbohydrate active modules/genes annotated. Results of the meta-analysis on the 2642 genomes revealed that some cellulosome gene clusters were in lack of the surface layer homology module (SLH) and microbe strains annotated with such cellulosome gene clusters were not certainly cellulolytic. Hypothesized in this study was that cellulosome-independent genes harboring both the SLH module and the cellulose-binding carbohydrate binding module (CBM) were likely an alternative gene apparatus initiating the formation of the cellulose-enzyme-microbe (CEM) complexes; and their role is important especially for the cellulolytic anaerobes without cellulosome gene clusters. ImportanceIn the genome-centric prediction on the corresponding microbes cellulolytic activity, recognition of the synergy machineries that include but are not limited to the cellulosome gene clusters is equally important as the annotation of the individual carbohydrate active modules or genes. This is the first time that a pipeline was developed for an automatic recognition of the synergy among the carbohydrate active units annotated. With promising resolution and reliability, this pipeline should be a good add to the bioinformatic tools for the genome-centric interpretations on the specific function niche of cellulose hydrolysis.

genomics↗

TagSeqTools: a flexible and comprehensive analysis pipeline for NAD tagSeq data

NAD tagSeq has recently been developed for the identification and characterization of NAD+-capped RNAs (NAD-RNAs). This method adopts a strategy of chemo-enzymatic reactions to label the NAD-RNAs with a synthetic RNA tag before subjecting to the Oxford Nanopore direct RNA sequencing. A computational tool designed for analyzing the sequencing data of tagged RNA will facilitate the broader application of this method. Hence, we introduce TagSeqTools as a flexible, general pipeline for the identification and quantification of tagged RNAs (i.e., NAD+-capped RNAs) using long-read transcriptome sequencing data generated by NAD tagSeq method. TagSeqTools comprises two major modules, TagSeek for differentiating tagged and untagged reads, and TagSeqQuant for the quantitative and further characterization analysis of genes and isoforms. Besides, the pipeline also integrates some advanced functions to identify antisense or splicing, and supports the data reformation for visualization. Therefore, TagSeqTools provides a convenient and comprehensive workflow for researchers to analyze the data produced by the NAD tagSeq method or other tagging-based experiments using Oxford nanopore direct RNA sequencing. The pipeline is available at https://github.com/dorothyzh/TagSeqTools, under Apache License 2.0.

bioinformatics↗

Latent Plasticity of Effector-like Exhausted CD8 T cells contributes to memory responses

Persistent antigen induces a dysfunctional CD8 T cell state known as T cell "exhaustion" characterized by expression of PD-1 and decreased effector functions. Nevertheless, dysfunctional CD8 T cells can mediate control of antigen burden which is long-lasting. While heterogeneity of exhausted CD8 T cells has been described, the cells which actively proliferate and exert viral control have remained elusive. Here, we define subsets of PD-1+ CD8 T cells during chronic infection marked by expression of CX3CR1 with substantial in situ proliferation and high expression of granzyme B. Moreover, these cells maintain the effector pool through self-renewal independently of previously defined stem-like cells. Unexpectedly, CX3CR1+ CD8 T cells retain plasticity to be reprogrammed to memory cells through expression of TCF-1 and re-gain polyfunctionality. Thus, we define a subset of effector-like exhausted CD8 T cells with capacity to contribute to the memory pool, offering a prime target for novel immunotherapies.

immunology↗

Vitamin D receptor protects against dysbiosis and tumorigenesis via the JAK/STAT pathway in intestine

BackgroundVitamin D exerts regulatory roles via vitamin D receptor (VDR) in mucosal immunity, host defense, and inflammation involving host factors and microbiome. Human Vdr gene variation shapes the microbiome and VDR deletion leads to dysbiosis. Low VDR expression and diminished vitamin D/VDR signaling are observed in colon cancer. Nevertheless, how intestinal epithelial VDR is involved in tumorigenesis through gut microbiota remains unknown. We hypothesized that intestinal VDR protects mice against dysbiosis via modulating the JAK/STAT pathway in tumorigenesis. To test our hypothesis, we used an azoxymethane/Dextran Sulfate Sodium-induced cancer model in intestinal VDR conditional knockout (VDR{Delta}IEC) mice, cell cultures, stem-cell derived colonoids, and human colon cancer samples. ResultsVDR{Delta}IEC mice have higher numbers of tumors with location shifted from distal to proximal colon. Fecal microbiota analysis showed that VDR deletion leads to bacterial profile shift from normal to susceptible carcinogenesis. We found enhanced bacterial staining in mouse and human tumors. Microbial metabolites from VDR{Delta}IEC mice showed elevated secondary bile acids, consistent with the observations in human CRC. We further identified that VDR protein bound to the Jak2 promoter, suggesting that VDR transcriptionally regulated Jak2. The JAK/STAT pathway is critical in intestinal and microbial homeostasis. Fecal samples from VDR{Delta}IEC mice activate the STAT3 activation in human and mouse organoids. Lack of VDR led to hyperfunction of Jak2 in respond to intestinal dysbiosis. A JAK/STAT inhibitor abolished the microbiome-induced activation of STAT3. ConclusionWe provide insights into the mechanism of VDR dysfunction leading to dysbiosis and tumorigenesis. It indicates a new target -- microbiome and VDR for prevention of cancer.

cancer biology↗

Dynamics of mcr-1 prevalence and mcr-1-positive Escherichia coli after the cessation of colistin use as a feed additive for animals in China: a prospective cross-sectional and whole genome sequencing based molecular epidemiological study

BackgroundThe global dissemination of colistin resistance encoded by mcr-1 has been attributed to extensive use of colistin in livestock, threatening colistin efficacy in medicine. The emergence of mcr-1 in common pathogens, such as Escherichia coli, is of particular concern. Therefore, China banned the use of colistin in animal feed from May 1ST 2017. We investigated subsequent changes in mcr-1 prevalence, and the genomic epidemiology of mcr-1-positive Escherichia coli (MCRPEC). MethodsSampling was conducted pre- (October-December 2016) and post-colistin ban (October-December, 2017 and 2018, respectively). 3675 non-duplicate pig fecal samples were collected from 14 provinces (66 farms) in China to determine intervention-related changes in mcr-1 prevalence. 15193 samples were collected from pigs, healthy human volunteers, colonized and infected hospital inpatients, food and the environment in Guangzhou, to characterize source-specific mcr-1 prevalence and the wider ecological impact of the ban. From these samples, 688 MCRPEC were analyzed with whole genome sequencing (WGS), plasmid conjugation and S1-PFGE/Southern blots to characterize associated genomic changes. FindingsAfter the ban, mcr-1 prevalence decreased significantly in national pig farms, from 45{middle dot}0% (308/684 samples) in 2016, to 19{middle dot}4% (274/1416) in 2018 (p<0{middle dot}0001). This trend was mirrored in samples from most sources in Guangzhou (overall 19{middle dot}2% [959/5003 samples] in 2016; 5{middle dot}3% [238/4489] in 2018; p<0{middle dot}0001). The population structure of MCRPEC was diverse (23 sequence clusters [SCs]); ST10 clonal complex isolates were predominant (247/688 [36%]). MCRPEC causing infection in hospitalized inpatients were genetically more distinct and appeared less affected by the ban. mcr-1 was predominantly found on plasmids (632/688 [92%]). Common mcr-1 plasmid types included IncX4, IncI2 and IncHI2 (502/656 [76.5%]); significant increases in IncI2-associated mcr-1 and a distinct lineage of mcr-1-associated IncHI2 were observed post-ban. Changes in the frequency of mcr-1-associated flanking sequences (ISApl1-negative MCRPEC), 63 core genome SNPs and 30 accessory genes were also significantly different after the ban, consistent with rapid genetic adaptation in response to changing selection pressures. InterpretationA rapid, ecosystem-wide, decline in mcr-1 was observed after banning the use of colistin in animal feed, with associated genetic changes in MCRPEC. Genomic surveillance is key to assessing and monitoring stewardship interventions. FundingNational Natural Science Foundation of China

microbiology↗

Novel culture method to diagnose fungal infections with biopsy tissues

Biopsy tissue is a difficult sample to gain for the identification of potential pathogen in the clinical laboratory. At present, there are no effective culture methods for small-sized biopsy tissue. In this study, we propose a novel tissue biopsy culture method based on Myco/F lytic liquid culture system, namely, tissue was grinded before injected into culture bottles. More types and numbers of fungi are cultivated using this culture system than sputum or BALF culture. A few of mycobacteria were also detected with ground tissues. The method may be a promising alternative to or supplement for the traditional plate culture in clinical practice.

microbiology↗

Salmonella Enteritidis Effector AvrA suppresses autophagy by reducing Beclin-1 protein

Autophagy is a cellular process to clear pathogens. Salmonella enterica serovar Enteritidis (S.E) has emerged as one of the most important food-borne pathogens. However, major studies still focus on Salmonella enterica serovar Typhimurium. Here, we reported that AvrA, a S. Enteritidis effector, inhibited autophagy to promote bacterial survival in the host. We found that AvrA regulates the conversion of LC3 I into LC3 II and the enrichment of lysosomes. Beclin-1, a key molecular regulator of autophagy, was decreased after AvrA expressed strain colonization. In S.E-AvrA--infected cells, we found the increases of protein levels of p-JNK and p-c-Jun and the transcription level of AP-1. AvrA-reduction of Beclin-1 protein expression is through the JNK pathway. The JNK inhibitor abolished the AvrA-reduced Beclin-1 protein expression. Moreover, we identified that the AvrA mutation C186A abolished its regulation of Beclin-1 expression. In addition, AvrA protein interacted with Beclin-1. In organoids and infected mice, we explored the physiologically related effects and mechanism of AvrA in reducing Beclin-1 through the JNK pathway, thus attenuating autophagic responses. ImportanceSalmonella Enteritidis is an important pathogen with a public health concern and farm production risk, yet the host-pathogen interactions that govern the survival of S. Enteritidis infections are incompletely understood. Anti-bacterial autophagy provides potent cell-autonomous immunity against bacterial colonization. Here, we report that a new role for effector AvrA of S. Enteritidis in the reduction of Beclin-1 protein expression through the JNK pathway and the attenuation of the autophagic response in intestinal epithelial cells. This finding not only indicates an important role of S. Enteritidis effector in reducing host protein as a strategy to suppress autophagy, but also suggests manipulating autophagy as a new strategy to treat infectious diseases.

microbiology↗

CNV-BAC: Copy Number Variation Detection in Bacterial Circular Genome

MotivationWhole genome sequencing (WGS) is widely used for copy number variation (CNV) detection. However, for most bacteria, their circular genome structure and high replication rate make reads more enriched near the replication origin. CNV detection based on read depth could be seriously influenced by such replication bias. ResultsWe show that the replication bias is widespread using ~200 bacterial WGS data. We develop CNV-BAC that can properly normalize the replication bias as well as other known biases in bacterial WGS data and can accurately detect CNVs. Simulation and real data analysis show that CNV-BAC achieves the best performance in CNV detection compared with available algorithms. Availability and implementationCNV-BAC is available at https://github.com/LinjieWu/CNV-BAC. Contactruibinxi@math.pku.edu.cn

bioinformatics↗

Phase separation-mediated formation of condensed GIT/PIX enzyme complex module for compartmentalized signaling

Cells compartmentalize enzymes for broad physiological functions such as efficient metabolic reactions and spatiotemporally controlled signaling. A given enzyme or enzyme complex can participate in multiple cellular processes in response to different signal inputs by forming different cellular compartments. Here, we demonstrate that association of GIT1 and {beta}-Pix, a pair of GTPase regulatory enzymes involved in diverse cellular processes, leads to autonomous condensation of the complex via phase separation without additional scaffolding molecules. The atomic structure of the GIT/PIX complex reveals the molecular basis governing the phase separation-mediated condensation of the GIT1/{beta}-Pix complex. Importantly, the GIT1/{beta}-Pix condensates can function as a versatile modular membrane-less organelle- like structure for distinct cellular compartmentalization by binding to upstream proteins such as Paxillin in focal adhesions, Shank3 in neuronal synapses, and Scribble in cellular junctions. Thus, phase separation-mediated formation of condensed enzyme complexes provides a powerful way of dynamically concentrating limited amounts of cooperating enzymes to specific cellular compartments for optimal signaling.

cell biology↗

The Genomic Loci of Specific Human tRNA Genes Exhibit Ageing-Related DNA Hypermethylation

The epigenome deteriorates with age, potentially impacting on ageing-related disease. Here, we interrogate the DNA methylation state of the genomic loci of human tRNA. Whilst arising from only ~46kb (<0.002% genome), this information transfer machinery is the second most abundant cellular transcript. tRNAs also control metabolic processes known to affect ageing, through core translational and additional regulatory roles. We identified a genomic enrichment for age-related DNA hypermethylation at tRNA loci. Analysis in 4,350 MeDIP-seq peripheral-blood DNA methylomes (16-82 years), classified 44 and 21 hypermethylating specific tRNAs at study- and genome-wide significance, respectively, contrasting with 0 hypomethylating. Validation and replication (450k array & independent targeted Bisuphite-sequencing) supported thehypermethylation of this functional unit. The strongest consistent signals, also independent of major cell-type change, occur in tRNA-iMet-CAT-1-4 and tRNA-Ser-AGA-2-6. This study is this first comprehensive evaluation of the genomic DNA methylation state of human tRNA genes and reveals a discreet hypermethylation with advancing age.

genomics↗

Ultra-low input single tube linked-read library method enables short-read NGS systems to generate highly accurate and economical long-range sequencing information for de novo genome assembly and haplotype phasing

Long-range sequencing information is required for haplotype phasing, de novo assembly and structural variation detection. Current long-read sequencing technologies can provide valuable long-range information but at a high cost with low accuracy and high DNA input requirement. We have developed a single-tube Transposase Enzyme Linked Long-read Sequencing (TELL-Seq) technology, which enables a low-cost, high-accuracy and high-throughput short-read next generation sequencer to routinely generate over 100 Kb long-range sequencing information with as little as 0.1 ng input material. In a PCR tube, millions of clonally barcoded beads are used to uniquely barcode long DNA molecules in an open bulk reaction without dilution and compartmentation. The barcode linked reads are used to successfully assemble genomes ranging from microbes to human. These linked-reads also generate mega-base-long phased blocks and provide a cost-effective tool for detecting structural variants in a genome, which are important to identify compound heterozygosity in recessive Mendelian diseases and discover genetic drivers and diagnostic biomarkers in cancers.

genomics↗

Dissemination of linezolid-resistance through sex pheromone plasmid transfer in Enterococcs faecalis

Despite recent recognition of the ATP-binding cassette protein OptrA as an important mediator of linezolid-resistance in Enterococcus faecalis worldwide, the mechanisms of optrA gene acquisition and transfer remain poorly understood. In this study, we performed comprehensive molecular and phenotypic profiling of 44 optrA-carrying E. faecalis clinical isolates with linezolid-resistance. Pulse-field gel electrophoresis and DNA hybridization revealed the presence of optrA in the plasmid in 26 (59%) isolates and in the chromosome in 18 (41%) isolates. Conjugation experiments showed a successful transfer of optrA in 88.5% (23/26) of isolates carrying optrA in plasmids while no transfer occurred in any isolates carrying optrA in the chromosome (0/18). All 23 transconjugants exhibited in vitro resistance to linezolid and several other antibiotics, and were confirmed to contain optrA and other resistance genes. Plasmid typing demonstrated a predominance (18/23 or 78%) of rep9-type plasmids (pCF10 prototype) known to be the best studied sex pheromone responsive plasmids. Full plasmid genome sequencing of one isolate revealed the presence of drug resistance genes (optrA and fexA) and multiple sex pheromone response genes in the same plasmid, which represents the first sex pheromone responsive plasmid carrying optrA from a clinical isolate. PCR-based genotyping revealed the presence of three key sex pheromone response genes (prgA, prgB and prgC) in almost all 23 optrA-carrying isolates tested. Finally, functional studies of these isolates by clumping induction assay detected different degrees of clumping in most of the 23 isolates. Our analysis strongly suggests that optrA-mediated linezolid-resistance can be widely disseminated through sex pheromone plasmid transfer.

microbiology↗

DRAMS: A Tool to Detect and Re-Align Mixed-up Samples for Integrative Studies of Multi-omics Data

Studies of complex disorders benefit from integrative analyses of multiple omics data. Yet, sample mix-ups frequently occur in multi-omics studies, weakening statistical power and risking false findings. Accurately aligning sample information, genotype, and corresponding omics data is critical for integrative analyses. We developed DRAMS (https://github.com/Yi-Jiang/DRAMS) to Detect and Re-Align Mixed-up Samples to address the sample mix-up problem. It uses a logistic regression model followed by a modified topological sorting algorithm to identify the potential true IDs based on data relationships of multi-omics. According to tests using simulated data, the more types of omics data used or the smaller the proportion of mix-ups, the better that DRAMS performs. Applying DRAMS to real data from the PsychENCODE BrainGVEX project, we detected and corrected 201 (12.5% of total data generated) mix-ups. Of the 21 mix-ups involving errors of racial identity, DRAMS re-assigned all samples to the correct racial cluster in the 1000 Genomes project. In doing so, quantitative trait loci (QTL) (FDR<0.01) increased by an average of 1.62-fold. The use of DRAMS in multi-omics studies will strengthen statistical power of the study and improve quality of the results. Even though very limited studies have multi-omics data in place, we expect such data will increase quickly with the needs of DRAMS.\n\nAuthor summarySample mix-up happens inevitably during sample collection, processing, and data management. It leads to reduced statistical power and sometimes false findings. It is of great importance to correct mixed-up samples before conducting any downstream analyses. We developed DRAMS to detect and re-align mixed-up samples in multi-omics studies. The basic idea of DRAMS is to align the data and labels for each sample leveraging the genetic information of multi-omics data. DRAMS corrects sample IDs following a two-step strategy. At first, it estimates pairwise genetic relatedness among all the data generated from all the individuals. Because the different data generated from the same individual should share the same genetics, we can cluster all the highly related data and consider that the data from one cluster have only one potential ID. Then, we used a \"majority vote\" strategy to infer the potential ID for individuals in each cluster. Other information, such as match of genetics-based and reported sexes, omics priorority, etc., were also used to direct identifying the potential IDs. It has been proved that DRAMS performs very well in both simulation and PsychENCODE BrainGVEX multi-omics data.

bioinformatics↗

A cell-free platform based on nisin biosynthesis for discovering novel lanthipeptides and guiding their overproduction in vivo

Lanthipeptides have extensive therapeutic and industrial applications; however, since many are bactericidal, traditional in vivo platforms are limited in their capacity to discover and mass produce novel lanthipeptides as bacterial organisms are often critical components in these systems. We developed a cell-free protein synthesis (CFPS) platform that enables rapid genome mining, screening and guiding overproduction of lanthipeptides in vivo. For proof-of-concept studies, the type I lanthipeptide, nisin, was selected. Four novel lanthipeptides with anti-bacterial activity were identified among all nisin analogs in the NCBI database in a single day. Further, we coupled the CFPS platform with a screening assay for gram-negative bacterial growth and identified a potent nisin mutant, M5. The titer of nisin and nisin analogs significantly improved with CFPS platform guidance. Owing to the similarities in biosynthesis, our CFPS platform is broadly applicable to other lanthipeptides, provides a universal method for lanthipeptides discovery and overproduction.

synthetic biology↗