Biology subjects

Zeng, Y.

Publications and source records attributed to Zeng, Y..

At least 199 records · Page 11Linked to original sources

bioRxiv2019

A tale of winglets: evolution of flight morphology in stick insects

The evolutionary transition between winglessness and a full-winged morphology requires selective advantage for intermediate forms. Conversely, repeated secondary wing reductions among the pterygotes indicates relaxation of such selection. However, evolutionary trajectories of such transitions are not well characterized. The stick insects (Phasmatodea) exhibit diverse wing sizes at both interspecific and intersexual levels, and thus provide a system for examining how selection on flight capability, along with other selective forces, drives the evolution of flight-related morphology. Here, we examine variation in relevant morphology for stick insects using data from 1100+ individuals representing 765 species. Although wing size varies along a continuous spectrum, taxa with either long or miniaturized wings are the most common, whereas those with intermediate-sized wings are relatively rare. In a morphological space defined by wing and body size, the aerodynamically relevant parameter termed wing loading (the average pressure exerted on the air by the wings) varies according to sex-specific scaling laws; volant but also flightless forms are the most common outcomes in both sexes. Using phylogenetically-informed analyses, we show that relative wing size and body size are inversely correlated in long-winged insects regardless of sexual differences in morphology and ecology. These results demonstrate the diversity of flight-related morphology in stick insects, and also provide a general framework for addressing evolutionary coupling between wing and body dimensions. We also find indirect evidence for a fitness valley associated with intermediate-sized wings, suggesting relatively rapid evolutionary transitions between wingless and volant forms.

evolutionary biology↗

bioRxiv2019

Single-cell tracing of the first hematopoietic stem cell generation in human embryos

Tracing the emergence of the first hematopoietic stem cells (HSCs) in human embryos, particularly the scarce and transient precursors thereof, is so far challenging, largely due to technical limitations and material rarity. Here, using single-cell RNA sequencing, we constructed the first genome-scale gene expression landscape covering the entire course of endothelial-to-HSC transition during human embryogenesis. The transcriptomically defined HSC-primed hemogenic endothelial cells (ECs) were captured at Carnegie stage 12-14 in an unbiased way, showing an unambiguous arterial EC feature with the up-regulation of RUNX1, MYB and ANGPT1. Importantly, subcategorizing CD34+CD45- ECs into CD44+ population strikingly enriched hemogenic ECs by over 10-fold. We further mapped the developmental path from arterial ECs via HSC-primed hemogenic ECs to hematopoietic stem progenitor cells, and revealed a distinct expression pattern of genes that were transiently over-represented upon the hemogenic fate choice of arterial ECs, including EMCN, PROCR and RUNX1T1. We also uncovered another temporally and molecularly distinct intra-embryonic hemogenic EC population, which was detected mainly at earlier CS 10 and lacked the arterial feature. Finally, we revealed the cellular components of the putative aortic niche and potential cellular interactions acting on the HSC-primed hemogenic ECs. The cellular and molecular programs and interactions that underlie the generation of the first HSCs from hemogenic ECs in human embryos, together with distinguishing HSC-primed hemogenic ECs from others, will shed light on the strategies for the production of clinically useful HSCs from pluripotent stem cells.

developmental biology↗

bioRxiv2019

In vivo sequestration of innate small molecules to promote bone healing

Approaches that enable innate repair mechanisms hold great potential for tissue repair. Herein, we describe biomaterial-assisted sequestration of small molecules to localize pro-regenerative signaling at the injury site. Specifically, we designed a synthetic biomaterial containing boronate molecules to sequester adenosine, a small molecule ubiquitously present in the human body. The biomaterial-assisted sequestration of adenosine leverages the transient surge of extracellular adenosine following injury to prolong local adenosine signaling. We demonstrated that implantation of the biomaterial patch following injury establishes an in-situ stockpile of adenosine, resulting in accelerated healing by promoting both osteoblastogenesis and angiogenesis. The adenosine content within the patch recedes to the physiological level as the tissue regenerates. In addition to sequestering endogenous adenosine, the biomaterial is also able to deliver exogenous adenosine to the site of injury, offering a versatile solution to utilizing adenosine as a potential therapeutic for tissue repair.

bioengineering↗

bioRxiv2019

Genomic sequencing of Phyllosticta citriasiana provide insight into its conservation and diversification with closely related Phyllosticta species associated with citrus

Phyllosticta citriasiana is the causal agent of the pomelo tan spot. Here, we presented the ~34Mb genome of P. citriasiana. The genome is organized in 92 contigs, encompassing 9202 predicted genes. Comparative genomic analyses with other two Phyllosticta species (P. citricarpa and P. capitalensis) associated with citrus was conducted to understand their evolutionary conservation and diversification. Pairwise genome alignments revealed that these species are highly syntenic. All species encode similar numbers of CAZymes and secreted proteins. However, the molecular functions of the secretome showed that each species contains some enzymes with distinct activities. Three Phyllosticta species shared a core set of 7261 protein families. P. capitalensis had the largest set of orphan genes (2040), in complete contrast to that of P. citriasiana (371) and P. citricarpa (262). Most of the orphan genes were functionally unknown, but they contain a certain number of species-specific secreted proteins. A total of 23 secondary metabolites (SM) biosynthesis clusters were identified in the three Phyllosticta species, 21 of them are highly conserved among these species while the remaining 2 showed whole cluster gain and loss polymorphisms or gene content polymorphisms. Taken together, our study reveals insights into the genetic mechanisms of host adaptation of Phyllosticta species associated with citrus and paves the way to identify effectors that function in infection of citrus plants.

genomics↗

bioRxiv2019

Identifying epigenetic biomarkers of established prognostic factors and survival in a clinical cohort of individuals with oropharyngeal cancer

Smoking status, alcohol consumption and HPV infection (acquired through sexual activity) are the predominant risk factors for oropharyngeal cancer and are thought to alter the prognosis of the disease. Here, we conduct epigenome-wide association studies (EWAS) of these factors and [~]3-year survival using Illumina Methylation EPIC blood DNA methylation profiles from 409 individuals in the Head and Neck 5000 (HN5000) study. CpG site associations below our multiple-testing threshold (PBonferroni < 0.05) with both a prognostic factor and with survival were observed in four gene regions: SPEG (smoking), GFI1 (smoking), PPT2 (smoking), and KHD3CL (alcohol consumption). These were further analysed using 2-step Mendelian randomization to assess whether methylation may be a causal mediator of cancer survival. Evidence for mediation was observed only in the SPEG gene region, showing an association with decreased survival (mortality HR: 1.28, 95% CI: 1.14 to 1.43, P: 2.12x10-05). Replication in data from independent datasets, and from HN5000 participants with longer follow-up times is needed to confirm these findings.

epidemiology↗

bioRxiv2019

T Lymphopoiesis from Pluripotent Stem Cells by Defined Transcription Factors at Single Cell Resolution

Achievement of immunocompetent and therapeutic T lymphopoiesis from pluripotent stem cells is a central aim in T cell regenerative medicine. To date, preferentially regenerating T lymphopoiesis in vivo from pluripotent stem cells (PSC) remains a practical challenge. Here we documented that synergistic and transient expression of Runx1 and Hoxa9 restricted in the time window of endothelial to hematopoietic transition and hematopoietic maturation stages induced in vitro from PSC (iR9-PSC) preferentially generated engraftable hematopoietic progenitors capable of homing to thymus and developing into mature T (iT) cells in primary and secondary immunodeficient recipients. Single-cell transcriptome and functional analyses illustrated the cellular trajectory of T lineage induction from PSC, unveiling the T-lineage specification determined at as early as hemogenic endothelial cell stage and identifying the bona fide pre-thymic progenitors. The iT cells distributed normally in central and peripheral lymphoid organs and exhibited abundant TCR{beta} repertoire. The regenerative T lymphopoiesis rescued the immune-surveillance ability in immunodeficient mice. Furthermore, gene-edited iR9-PSC produced tumor-specific-T cells in vivo that effectively eradicated tumor cells. This study provides insight into universal generation of functional and therapeutic T lymphopoiesis from the unlimited and editable PSC source.

immunology↗

bioRxiv2019

Proteome-by-phenome Mendelian Randomisation detects 38 proteins with causal roles in human diseases and traits

Target identification remains a crucial challenge in drug development. To enable unbiased detection of proteins and pathways that have a causal role in disease pathogenesis or progression, we propose proteome-by-phenome Mendelian Randomisation (P2MR). We first detected genetic variants associated with plasma concentration of 249 proteins. We then used 64 replicated variants in two-sample Mendelian Randomisation to quantify evidence of a causal role for each protein across 846 phenotypes: this yielded 509 robust protein-outcome links. P2MR provides substantial promise for drug target prioritisation. We provide confirmatory evidence for a causal role for the proteins encoded at multiple cardiovascular disease risk loci (FGF5, IL6R, LPL, LTA), and discovered that intestinal fatty acid binding protein (FABP2) contributes to disease pathogenesis. Additionally, we find and replicate evidence for a causal role of tyrosine-protein phosphatase non-receptor type substrate 1 (SHPS1; SIRPA) in schizophrenia. Our results provide specific prediction of the effects of changes of plasma protein concentration on complex phenotypes in humans.

genomics↗

bioRxiv2019

Pair-wise Comparison Analysis for Multiple Pool-sep: an efficient method identified anthocyanin biosynthesis genes in rice pericarp

The complex traits are derived from multiple genes and exhibit a large variety of phenotypes. High-throughput sequencing technologies have become the new strategies for mapping the important traits of crops. However, these methods have their own disadvantages and limitations. Here we introduced Pair-wise Comparison Analysis for Multiple Pool-seq (PCAMP) for mapping the candidate genomic regions involved in anthocyanin biosynthesis in rice pericarp. In this protocol, the second filial generation (F2) populations obtained by crossing two parents with different target traits were divided into n (n>=3) subpopulations according to their phenotypes. Thirty phenotypically identical individuals were selected from each subpopulation and DNA samples were extracted to form a pool for sequencing. Finally, we compared the SNP-index between every two Pool-seqs to map the candidate genomic regions. We applied PCAMP to analyse F2 populations and successfully identified five known genes and five new candidate genomic regions for anthocyanin biosynthesis in rice pericarp. These results demonstrate that PCAMP is an efficient new method for dissecting the complex traits of crops.

molecular biology↗

bioRxiv2018

Highly multiplexed in situ protein imaging with signal amplification by Immuno-SABER

Probing the molecular organization of tissues requires in situ analysis by microscopy. However current limitations in multiplexing, sensitivity, and throughput collectively constitute a major barrier for comprehensive single-cell profiling of proteins. Here, we report Immunostaining with Signal Amplification By Exchange Reaction (Immuno-SABER), a rapid, highly multiplexed signal amplification method that simultaneously tackles these key challenges. Immuno-SABER utilizes DNA-barcoded antibodies and provides a method for highly multiplexed signal amplification via modular orthogonal DNA concatemers generated by Primer Exchange Reaction. This approach offers the capability to preprogram and control the amplification level independently for multiple targets without in situ enzymatic reactions, and the intrinsic scalability to rapidly amplify and image a large number of protein targets. We validated our approach in diverse sample types including cultured cells, cryosections, FFPE sections, and whole mount tissues. We demonstrated independently tunable 5-180-fold amplification for multiple targets, covering the full signal range conventionally achieved by secondary antibodies to tyramide signal amplification, as well as simultaneous signal amplification for 10 different proteins using standard equipment and workflow. We further combined Immuno-SABER with Expansion Microscopy to enable rapid and highly multiplexed super-resolution tissue imaging. Overall, Immuno-SABER presents an effective and accessible platform for rapid, multiplexed imaging of proteins across scales with high sensitivity.

cell biology↗

bioRxiv2018

Consensus interpretation of the Met34Thr and Val37Ile variants in GJB2 by the ClinGen Hearing Loss Expert Panel

PURPOSEPathogenic variants in GJB2 are the most common cause of autosomal recessive sensorineural hearing loss. The classification of c.101T>C/p.Met34Thr and c.109G>A/p.Val37Ile in GJB2 are controversial. Therefore, an expert consensus is required for the interpretation of these two variants.\n\nMETHODSThe ClinGen Hearing Loss Expert Panel (HL-EP) collected published data and shared unpublished information from participating laboratories regarding the two variants. Functional, computational, allelic, and segregation data were also obtained.\n\nRESULTSThe panel reviewed the synthesized information, and classified the Met34Thr and Val37Ile variants according to professional variant interpretation guidelines. We found that Met34Thr and Val37Ile are significantly overrepresented in hearing loss patients, compared to the general population. Met34Thr or Val37Ile homozygotes or compound heterozygotes typically manifest mild to moderate hearing loss. Several other types of evidence also support pathogenic roles for those two variants.\n\nCONCLUSIONResolving controversies in variant classification requires coordinated effort among a panel of international multi-institutional experts to share data, standardize classification rules, review evidence, and reach a consensus. The ClinGen HL-EP concluded that Met34Thr and Val37Ile variants in GJB2 are pathogenic for autosomal recessive nonsyndromic hearing loss with variable expressivity and age-dependent penetrance.

genetics↗

bioRxiv2018

Membrane curvature sensing of the lipid-anchored K-Ras small GTPases

Cell morphologies, defined by plasma membrane (PM) local curvature, change during mitogen-dependent function and pathology, such as growth, division and proliferation. The lipid-anchored Ras small GTPases are essential upstream regulators of the mitogen-activated protein kinases (MAPKs) cascades and play key roles in many pathological conditions, especially cancer. Ras signaling is mostly compartmentalized to the cell PM through the formation of nanometer-sized domains, termed as nanoclusters, and undergo selective lipid sorting for efficient effector recruitment and activation. Thus, Ras function might be sensitive to changing PM curvature, potentially regulating mechanosensing of mitogen signaling. We employed nanofabrication and super-resolution imaging and found that Ras functions respond to PM curvature modulations in an isoform specific manner: nanoclustering and signaling of the most oncogenically prevalent isoform K-Ras favor less curved PM, while those of another isoform H-Ras favor more curved PM. We then examined whether Ras membrane curvature sensing is mediated by lipid sorting. We found that anionic phospholipids sense changing PM curvature in distinct manners: phosphatidylserine (PS) localization shows preference for less curved membrane but phosphoinositol 4,5-bisphosphate (PIP2) localization favors more curved PM. Depletion of endogenous PS abolishes K-Ras PM curvature sensing. Exogenous PS addback and synthetic bilayer binding assays further show that only mixed-chain PS species, but not other PS species, mediate K-Ras curvature sensing. Taken together, the Ras proteolipid nano-assemblies on the PM act as relay stations to convert mechanical stimulations to mitogenic signaling circuits, thus a novel mechanism for cancer cell mechanotransduction

biochemistry↗

bioRxiv2018

Culturomics of Aerobic Anoxygenic Phototrophic Bacteria in Wheat Phyllosphere Revealed a Divergent Evolutionary Pattern of Photosynthesis Genes in Methylobacterium spp.

The phyllosphere is a habitat to a variety of viruses, bacteria, fungi and other microorganisms, which play a fundamental role in maintaining the health of plants and mediating the interaction between plants and ambient environments. A recent addition to this catalogue of microbial diversity was the aerobic anoxygenic phototrophs (AAPs), a group of widespread bacteria that absorb light through bacteriochlorophyll (BChl a) to produce energy without fixing carbon or producing molecular oxygen. However, culture representatives of AAPs from phyllosphere and their genome information are lacking, limiting our capability to assess their potential ecological roles in this unique niche. In this study, we investigated the presence of AAPs in the phyllosphere of a winter wheat (Triticum aestivum L.) in Denmark by employing bacterial colony based infrared imaging and MALDI-TOF mass spectrometry (MS) techniques. A total of ~4480 colonies were screened for the presence of cellular BChl a, resulting in 129 AAP isolates that were further clustered into 25 groups based on MALDI-TOF MS profiling, representatives of which were sequenced using the Illumina NextSeq and Oxford Nanopore MinION platforms. Twenty draft and five complete genomes of AAPs were assembled belonging in Methylobacterium, Rhizobium, Roseomonas and a novel strain in Methylocystaceae. We observed a diverging pattern in the evolutionary rates of photosynthesis genes among the highly homogenous AAP strains of Methylobacterium (Alphaproteobacteria), highlighting an ongoing genomic innovation at the gene cluster level.

microbiology↗

bioRxiv2018

Identification of novel differentially methylated sites with potential as clinical predictors of impaired respiratory function and COPD

BackgroundThe causes of poor respiratory function and COPD are incompletely understood, but it is clear that genes and the environment play a role. As DNA methylation is under both genetic and environmental control, we hypothesised that investigation of differential methylation associated with these phenotypes would permit mechanistic insights, and improve prediction of COPD. We investigated genome-wide differential DNA methylation patterns using the recently released 850K Illumina EPIC array in the largest single population sample to date.\n\nMethodsEpigenome-wide association studies (EWASs) of respiratory function and COPD were performed in peripheral blood samples from the Generation Scotland: Scottish Family Health Study (GS:SFHS) cohort (N=3,791; 274 COPD cases and 2,928 controls). In independent COPD incidence data (N=150), significantly differentially methylated sites (DMSs; p<3.6x10-8) were evaluated for their added predictive power when added to a model including clinical variables, age, sex, height and smoking history using receiver operating characteristic analysis. The Lothian Birth Cohort 1936 (LBC1936) was used to replicate association (N=895) and prediction (N=178) results.\n\nFindingsWe identified 29 respiratory function and/or COPD associated DMSs, which mapped to genes involved in alternative splicing, JAK-STAT signalling, and axon guidance. In prediction analyses, we observed significant improvement in discrimination between COPD cases and controls (p<0.05) in independent GS:SFHS (p=0.014) and LBC1936 (p=0.018) datasets by adding DMSs to a clinical model.\n\nInterpretationIdentification of novel DMSs has provided insight into the molecular mechanisms regulating respiratory function and aided prediction of COPD risk.\n\nFundingWellcome Trust Strategic Award 10436/Z/14/Z.\n\nResearch in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched for articles in PubMed published in English up to July 25, 2018, with the search terms \"DNA methylation\" and \"respiratory function\", or \"COPD\". We found some evidence for association between differential DNA methylation and both respiratory function and COPD. Of the twelve previous studies identified, eight used peripheral blood samples (sample size [N] range = 100-1,085) and four used lung tissue samples (N range = 24-160). The number of CpG loci analysed range from 27,578 to 485,512. These studies have not identified consistent changes in methylation, most likely due to a combination of factors including small sample sizes, technical issues, phenotypic definitions, and study design. In addition, no previous study has: analysed a sample from a large single cohort; used the recently released Illumina EPIC array (which assesses ~850,000 CpG loci); adjusted methylation data and phenotype for smoking history, or used both prevalent and incident COPD electronic health record data.\n\nAdded value of this studyTo our knowledge, this is the largest single cohort epigenome-wide association study (EWAS) of respiratory function and COPD to date (N=3,791). After applying stringent genome-wide significance criteria (P <3.6x10-8), we found that DNA methylation levels at 29 CpG sites in peripheral blood were associated with respiratory function or COPD. Of these 29, seven were testable in an independent population sample: all seven showed consistent direction of effect between the two samples and three showed replication (p<0.007 [0.05/7 CpG sites tested]). Our results suggest that adjustment of both the phenotypic and the DNA methylation probe data for smoking history, which has not been carried out in previous studies, reduces the confounding effects of smoking, identifies larger numbers of associations, and reduces the heterogeneity of effects across smoking strata. We used gene set enrichment and pathway analyses, together with an approach that combines DNA methylation results with gene expression data to provide evidence for enrichment of differentially methylated sites in genes linked to alternative splicing, and JAK-STAT signalling and axon guidance. Finally, we demonstrated that the inclusion of DNA methylation data improves COPD risk prediction over established clinical variables alone in two independent datasets.\n\nImplications of all the available evidenceThere is now accumulating evidence that DNA methylation in peripheral blood is associated with respiratory function and COPD.\n\nOur study has shown that DNA methylation levels at 29 CpG sites are robustly associated with respiratory function and COPD, provide mechanistic insights, and can improve prediction of COPD risk. Further studies are warranted to improve understanding of the aetiology of COPD and to assess the utility of DNA methylation profiling in the clinical management of this condition.

genomics↗

bioRxiv2018

Cytologic, Genetic, and Proteomic Analysis of a Yellow Leaf Mutant of Sesame (Sesamum indicum L.), Siyl-1

Leaf color mutation in sesame always affects the growth and development of plantlets, and their yield. To clarify the mechanisms underlying leaf color regulation in sesame, we analyzed a yellow-green leaf mutant. Genetic analysis of the mutant selfing revealed 3 phenotypes--YY, light-yellow (lethal); Yy, yellow-green; and yy, normal green--controlled by an incompletely dominant nuclear gene, Siyl-1. In YY and Yy, the number and morphological structure of the chloroplast changed evidently, with disordered inner matter, and significantly decreased chlorophyll content. To explore the regulation mechanism of leaf color mutation, the proteins expressed among YY, Yy, and yy were analyzed. All 98 differentially expressed proteins (DEPs) were classified into 5 functional groups, in which photosynthesis and energy metabolism (82.7%) occupied a dominant position. Our findings provide the basis for further molecular mechanism and biochemical effect analysis of yellow leaf mutants in plants.

genetics↗

bioRxiv2018

Association of SRB1, ITGB2 gene polymorphisms with coronary heart disease in Chinese Han population

BackgroundPrevious studies in mice and humans have implicated the lipoprotein receptor SRB1 in association with atherosclerosis and lipid levels. In our previous proteomics research, the expression of ITGB2 has differences between epicardial and subcutaneous adipose tissue. However, the association between the reported variants and risk of coronary heart disease (CHD) was not confirmed.\n\nMethodsWe conducted a case-control study consisted of 496 CHD patients and 367 controls. The two groups are adjusted for age, sex, body mass index, diabetes status and the proportion of dyslipidemia. The genotypes and allele frequency of variants rs838880,rs5888,rs5889 in SRB1 and rs235326,rs2070947,rs2070946 in ITGB2 were determined using Sequenom Mass-ARRAY technology.\n\nResultsThe genotypes frequencies of all the six SNPs were consistent with Hardy-Weinberg Equilibrium test. For gene SRB1 rs838880, there was a significant difference in the alleles frequency(p=0.017), genotype frequency(p=0.0028), recessive model (p=0.000672) between CHD group and control group. For gene ITGB2 rs2070947, there was a significant difference in the recessive model (p=0.03). By comparing the clinical and serum metabolic indexes of SNP sites by genotype we find that among three genotypes of SRB1 rs5888,there were significant difference in the level of dyslipidemia history and serum LPA, among three genotypes of ITGB2 rs235236,there were significant difference in the levels of serum HDL,APOA1 and hypertension history, among three genotypes of ITGB2 rs2070947,there were significant difference in the level of serum APOA1,hsCRP.\n\nConclusionsOur findings indicated that SNP rs838880 of gene SRB1 and rs2070947 of gene ITGB2 are associated with the risk of CHD in Chinese han population.

genetics↗

bioRxiv2018

Association of whole-genome and NETRIN1 signaling pathway-derived polygenic risk scores for Major Depressive Disorder and thalamic radiation white matter microstructure in UK Biobank

BackgroundMajor Depressive Disorder (MDD) is a clinically heterogeneous psychiatric disorder with a polygenic architecture. Genome-wide association studies have identified a number of risk-associated variants across the genome, and growing evidence of NETRIN1 pathway involvement. Stratifying disease risk by genetic variation within the NETRIN1 pathway may provide an important route for identification of disease mechanisms by focusing on a specific process excluding heterogeneous risk-associated variation in other pathways. Here, we sought to investigate whether MDD polygenic risk scores derived from the NETRIN1 signaling pathway (NETRIN1-PRS) and the whole genome excluding NETRIN1 pathway genes (genomic-PRS) were associated with white matter integrity.\n\nMethodsWe used two diffusion tensor imaging measures, fractional anisotropy (FA) and mean diffusivity (MD), in the most up-to-date UK Biobank neuroimaging data release (FA: N = 6,401; MD: N = 6,390).\n\nResultsWe found significantly lower FA in the superior longitudinal fasciculus ({beta} = -0.035, pcorrected = 0.029) and significantly higher MD in a global measure of thalamic radiations ({beta} = 0.029, pcorrected = 0.021), as well as higher MD in the superior ({beta} = 0.034, pcorrected = 0.039) and inferior ({beta} = 0.029, pcorrected = 0.043) longitudinal fasciculus and in the anterior ({beta} = 0.025, pcorrected = 0.046) and superior ({beta} = 0.027, pcorrected = 0.043) thalamic radiation associated with NETRIN1-PRS. Genomic-PRS was also associated with lower FA and higher MD in several tracts.\n\nConclusionsOur findings indicate that variation in the NETRIN1 signaling pathway may confer risk for MDD through effects on thalamic radiation white matter microstructure.

genetics↗

bioRxiv2018

VirTect: a computational method for detecting virus species from RNA-Seq and its application in head and neck squamous cell carcinoma

Next generation sequencing (NGS) provides an opportunity to detect viral species from RNA-seq data on human tissues, but existing computational approaches do not perform optimally on clinical samples. We developed a bioinformatics method called VirTect for detecting viruses in neoplastic human tissues using RNA-seq data. Here, we used VirTect to analyze RNA-seq data from 363 HNSCC (head and neck squamous cell carcinoma) patients and identified 22 HPV-induced HNSCCs. These predictions were validated by manual review of pathology reports on histopathologic specimens. Compared to two existing prediction methods, VirusFinder and VirusSeq, VirTect demonstrated superior performance with many fewer false positives and false negatives. The majority of HPV carcinogenesis studies thus far have been performed on cervical cancer and generalized to HNSCC. Our results suggest that HPV-induced HNSCC involves unique mechanisms of carcinogenesis, so understanding these molecular mechanisms will have a significant impact on therapeutic approaches and outcomes. In summary, VirTect can be an effective solution for the detection of viruses with NGS data, and can facilitate the clinicopathologic characterization of various types of cancers with broad applications for oncology.\n\nSignificance StatementWe developed a new bioinformatics tool, and reported the new inside of HPV carcinogenesis mechanism in HPV-induced head and neck squamous cell carcinoma (HNSCC). This novel bioin-formatics tool and the new knowledge of HPV-induced HNSCC will facilitate the development of target therapies for treating HNSCC.

bioinformatics↗

bioRxiv2018

Identification of candidate genes for gelatinization temperature, gel consistency and pericarp color by GWAS in rice based on SLAF-sequencing

Rice is an important cereal in the world, uncovering the genetic basis of agronomic traits in rice landraces genes associated with agronomically important traits is indispensable for both understanding the genetic basis of phenotypic variation and efficient crop improvement. Gelatinization temperature, gel consistency and pericarp color are important indices of rice cooking and eating quality evaluation and potential nutritional importance, which attract wide attentions in the application of genetic and breeding. To dissect the genetic basis of gelatinization temperature (GT), gel consistency (GC) and pericarp color (PC), a total of 419 rice landraces core germplasm collections consisting of 330 indica lines, 78 japonica lines and 11 uncertain varieties were grown, collected, then GT, GC, PC were measured for two years, and sequenced using Specific Locus Amplified Fragment Sequencing (SLAF) technology. In this study, 261,385,070 clean reads and 56,768 polymorphic SLAF tags were obtained, which a total of 211,818 single nucleotide polymorphisms (SNPs) were discovered. With 208,993 SNPs meeting the criterion of minor allele frequency (MAF) > 0.05 and integrity> 0.5, the phylogenetic tree and population structure analysis were performed for all 419 rice landraces, and the whole panel mainly separated into six subpopulations based on population structure analysis. Genome-wide association study (GWAS) was carried out for the whole panel, indica subpanel and japonica subpanel with subset SNPs respectively. One quantitative trait locus (QTL) on chromosome 6 for GT was detected in the whole panel and indica subpanel, and one QTL associated with GC was located on chromosome 6 in the whole panel and indica subpanel. For the PC trait, 8 QTLs were detected in the whole panel on chromosome 1, 3, 4, 7, 8, 10 and 11, and 7 QTLs in the indica subpanel on chromosome 3, 4, 7, 8, 10 and 11. The loci on chromosome 3, 8, 10 and 11 have not been identified previously, and they may be the candidate genes of pericarp color. For the three traits, no QTL was detected in japonica subpanel probably because of the polymorphism repartition between the subpanel, or small population size of japonica subpanel. This paper provides new gene resources and insights into the molecular mechanisms of important agricultural trait of rice phenotypic variation and genetic improvement of rice quality variety breeding.

genomics↗