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Ma, Y.

Publications and source records attributed to Ma, Y..

At least 361 records · Page 20Linked to original sources

The P3 O-Tert-Butyl-Threonine is Key to High Cellular and Antiviral Potency for Aldehyde-Based SARS-CoV-2 Main Protease Inhibitors

As an essential enzyme to SARS-CoV-2, main protease (MPro) is a viable target to develop antivirals for the treatment of COVID-19. By varying chemical compositions at both P2 and P3 sites and the N-terminal protection group, we synthesized a series of MPro inhibitors that contain {beta}-(S-2-oxopyrrolidin-3-yl)-alaninal at the P1 site. These inhibitors have a large variation of determined IC50 values that range from 4.8 to 650 nM. The determined IC50 values reveal that relatively small side chains at both P2 and P3 sites are favorable for achieving high in vitro MPro inhibition potency, the P3 site is tolerable toward unnatural amino acids with two alkyl substituents on the -carbon, and the inhibition potency is sensitive toward the N-terminal protection group. X-ray crystal structures of MPro bound with 16 inhibitors were determined. All structures show similar binding patterns of inhibitors at the MPro active site. A covalent interaction between the active site cysteine and a bound inhibitor was observed in all structures. In MPro, large structural variations were observed on residues N142 and Q189. All inhibitors were also characterized on their inhibition of MPro in 293T cells, which revealed their in cellulo potency that is drastically different from their in vitro enzyme inhibition potency. Inhibitors that showed high in cellulo potency all contain O-tert-butyl-threonine at the P3 site. Based on the current and a previous study, we conclude that O-tert-butyl-threonine at the P3 site is a key component to achieve high cellular and antiviral potency for peptidyl aldehyde inhibitors of MPro. This finding will be critical to the development of novel antivirals to address the current global emergency of concerning the COVID-19 pandemic.

biochemistry↗

The N-Terminal Carbamate is Key to High Cellular and Antiviral Potency for Boceprevir-Based SARS-CoV-2 Main Protease Inhibitors

Boceprevir is an HCV NSP3 inhibitor that has been explored as a repurposed drug for COVID-19. It inhibits the SARS-CoV-2 main protease (MPro) and contains an -ketoamide warhead, a P1 {beta}-cyclobutylalanyl moiety, a P2 dimethylcyclopropylproline, a P3 tert-butyl-glycine, and a P4 N-terminal tert-butylcarbamide. By introducing modifications at all four positions, we synthesized 20 boceprevir-based MPro inhibitors including PF-07321332 and characterized their MPro inhibition potency in test tubes (in vitro) and human host cells (in cellulo). Crystal structures of MPro bound with 10 inhibitors and antiviral potency of 4 inhibitors were characterized as well. Replacing the P1 site with a {beta}-(S-2-oxopyrrolidin-3-yl)-alanyl (opal) residue and the warhead with an aldehyde leads to high in vitro potency. The original moieties at P2, P3 and the P4 N-terminal cap positions in boceprevir are better than other tested chemical moieties for high in vitro potency. In crystal structures, all inhibitors form a covalent adduct with the MPro active site cysteine. The P1 opal residue, P2 dimethylcyclopropylproline and P4 N-terminal tert-butylcarbamide make strong hydrophobic interactions with MPro, explaining high in vitro potency of inhibitors that contain these moieties. A unique observation was made with an inhibitor that contains an P4 N-terminal isovaleramide. In its MPro complex structure, the P4 N-terminal isovaleramide is tucked deep in a small pocket of MPro that originally recognizes a P4 alanine side chain in a substrate. Although all inhibitors show high in vitro potency, they have drastically different in cellulo potency in inhibiting ectopically expressed MPro in human 293T cells. All inhibitors including PF-07321332 with a P4 N-terminal carbamide or amide have low in cellulo potency. This trend is reversed when the P4 N-terminal cap is changed to a carbamate. The installation of a P3 O-tert-butyl-threonine improves in cellulo potency. Three molecules that contain a P4 N-terminal carbamate were advanced to antiviral tests on three SARS-CoV-2 variants. They all have high potency with EC50 values around 1 M. A control compound with a nitrile warhead and a P4 N-terminal amide has undetectable antiviral potency. Based on all observations, we conclude that a P4 N-terminal carbamate in a boceprevir derivative is key for high antiviral potency against SARS-CoV-2.

biochemistry↗

Digital restoration of the pectoral girdles of two Early Cretaceous birds, and implications for early flight evolution

Pectoral girdle morphology is a key determinant of flight capability, but in some respects is poorly known among stem birds. Here, we reconstruct the pectoral girdles of the Early Cretaceous birds Sapeornis and Piscivorenantiornis based on computed tomography and three-dimensional visualization, revealing key morphological details. Enantiornithines such as Piscivorenantiornis have a uniquely localized scapula-coracoid joint, with only one area of articulation. This single articulation contrasts with the double articulation widely present in non-enantiornithine pennaraptoran theropods, including Sapeornis and crown birds, which comprises main and subsidiary articular contacts. A partially closed triosseal canal occurs in non-euornithine birds, representing a transitional stage in flight apparatus evolution. Numerous modifications of the pectoral girdle along the line to crown birds, and lineage-specific pectoral girdle variations, produced diverse pectoral girdle morphologies among Mesozoic birds, which ensured that a commensurate range of capability levels and modes emerged during the early evolution of flight.

evolutionary biology↗

Cryo-EM structure of an amyloid fibril formed by full-length human SOD1 reveals its pathological conformational conversion

Amyotrophic lateral sclerosis (ALS) is a progressive, fatal neurodegenerative disease characterized by the selective death of motor neurons. Misfolded Cu, Zn-superoxide dismutase (SOD1) has been linked to both familial ALS and sporadic ALS. SOD1 fibrils formed in vitro are able to incorporate into cells, transmit intercellularly, and share toxic properties with ALS inclusions. Here we produced amyloid fibrils in vitro from recombinant, full-length apo human SOD1 under semi-reducing conditions and determined the atomic structure using cryo-EM. The SOD1 fibril consists of a single protofibril with a left-handed helix. The fibril core exhibits a serpentine fold comprising N-terminal segment (residues 3 to 55) and C-terminal segment (residues 86 to 153) with a structural break. The two segments are zipped up by three salt bridge pairs. By comparison with the structure of apo SOD1 dimer, we propose that eight {beta}-strands (to form a {beta}-barrel) and one -helix in the subunit of apo SOD1 convert into thirteen {beta}-strands stabilized by five hydrophobic cavities in the SOD1 fibril. Our data provide insights into how SOD1 converts between structurally and functionally distinct states.

biochemistry↗

The p53 transactivation domain 1-dependent response to acute DNA damage in endothelial cells protects against radiation-induced cardiac injury

Thoracic radiation therapy can cause endothelial injury in the heart, leading to cardiac dysfunction and heart failure. Although it has been demonstrated that the tumor suppressor p53 functions in endothelial cells to prevent the development of radiation-induced myocardial injury, the key mechanism(s) by which p53 regulates the radiosensitivity of cardiac endothelial cells is not completely understood. Here, we utilized genetically engineered mice that express mutations in p53 transactivation domain 1 (TAD1) (p5325,26) or mutations in p53 TAD1 and TAD2 (p5325,26,53,54) specifically in endothelial cells to study the p53 transcriptional program that protects cardiac endothelial cells from ionizing radiation in vivo. p5325,26,53,54 loses the ability to drive transactivation of p53 target genes after irradiation while p5325,26 can induce transcription of a group of non-canonical p53 target genes, but not the majority of classic radiation-induced p53 targets critical for p53-mediated cell cycle arrest and apoptosis. After 12 Gy whole-heart irradiation, we found that both p5325,26 and p5325,26,53,54 sensitized mice to radiation-induced cardiac injury, in contrast to wild-type p53. Histopathological examination suggested that mutation of TAD1 contributes to myocardial necrosis after whole-heart irradiation, while mutation of both TAD1 and TAD2 abolishes the ability of p53 to prevent radiation-induced heart disease. Taken together, our results show that the transcriptional program downstream of p53 TAD1, which activates the acute DNA damage response after irradiation, is necessary to protect cardiac endothelial cells from radiation injury in vivo.

genetics↗

The manipulation of spinal motor neuron axonal growth promotes spinal cord repair

The loss of motor function in patients with spinal cord injury (SCI) is primarily due to the severing of the corticospinal tract (CST). Spinal motor neurons are located in the anterior horn of the spinal cord, and as the lower neurons of the CST, they control voluntary movement. Furthermore, its intrinsic axonal growth ability is significantly stronger than that of cerebral cortex pyramid neurons, which are the upper CST neurons. Therefore, we established an axonal regeneration model of spinal motor neurons to investigate the feasibility of repairing SCI by promoting axonal regeneration of spinal motor neurons. We demonstrated that conditionally knocking out pten in mature spinal motor neurons drastically enhanced axonal regeneration in vivo, and the regenerating axons of the spinal motor neurons re-established synapses with other cells in the damaged spinal cord. Thus, this strategy may serve as a novel and effective treatment method for SCI.

neuroscience↗

Fast anther dehiscence state recognition system establishing by deep learning to screen heat tolerant cotton

Cotton is one of the most economically important crops in the world. The fertility of male reproductive organs is a key determinant of cotton yield. The anther dehiscence or indehiscence directly determine the probability of fertilization in cotton. Thus, the rapid and accurate identification of cotton anther dehiscence status is important for judging anther growth status and promoting genetic breeding research. The development of computer vision technology and the advent of big data have prompted the application of deep learning techniques to agricultural phenotype research. Therefore, two deep learning models (Faster R-CNN and YOLOv5) were proposed to detect the number and dehiscence status of anthers. The single-stage model based on YOLOv5 has higher recognition efficiency and the ability to deploy to the mobile end. Breeding researchers can apply this model to terminals to achieve a more intuitive understanding of cotton anther dehiscence status. Moreover, three improvement strategies of Faster R-CNN model were proposed, the improved model has higher detection accuracy than YOLOv5 model. In addition, the percentage of dehiscent anther of randomly selected 30 cotton varieties were observed from cotton population under normal temperature and high temperature (HT) conditions through the integrated Faster R-CNN model and manual observation. The result showed HT varying decreased the percentage of dehiscent anther in different cotton lines, consistent with the manual method. Thus, this system can help us to rapid and accurate identification of HT-tolerant cotton. One sentence summaryThe deep learning technique was applied to identify the anther dehiscence state for the first time to quickly screen heat tolerant cotton varieties and help to explore key genetic improvement genes.

bioengineering↗

Oxytocinergic modulation of stress-associated amygdala-hippocampus pathways in humans is specially mediated by serotonergic mechanisms

BackgroundThe hypothalamic neuropeptide oxytocin (OXT) may exert anxiolytic and stress-reducing actions via modulatory effects on amygdala circuits. Animal models and initial findings in humans suggest that some of these effects are mediated by interactions with other neurotransmitter systems, in particular the serotonin (5-HT) system. Against this background, the present pharmacological resting state fMRI study aimed at determining whether effects of OXT on stress-associated amygdala intrinsic networks are mediated by 5-HT. MethodsWe employed a randomized placebo-controlled double-blind parallel-group pharmacological fMRI resting state experiment during which n = 112 healthy male participants underwent a transient decrease in 5-HT signaling via acute tryptophan depletion (ATD) or the corresponding placebo-control protocols (ATDc) before the administration of intranasal OXT or placebo intranasal spray, respectively. ResultsOXT and 5-HT modulation exerted interactive effects on the coupling of the left amygdala with the ipsilateral hippocampus and adjacent midbrain. OXT increased intrinsic coupling in this pathway, while this effect of OXT was significantly attenuated during transiently decreased central serotonergic signaling induced via ATD. In the absence of OXT or 5-HT modulation this pathway showed a trend for an association with self-reported stress perception in everyday life. No interactive effects were observed for the right amygdala. ConclusionsTogether, the findings provide first evidence that effects of OXT on stress-associated amygdala-hippocampal-midbrain pathways are critically mediated by the 5-HT system in men.

neuroscience↗

Nucleobase clustering contributes to the formation and hollowing of repeat-expansion RNA condensate

RNA molecules with repeat expansion sequences can phase separate into gel-like condensate, and this process may lead to neurodegenerative diseases. Here we report that in the presence of Mg2+ ion, RNA molecules containing 20xCAG repeats coacervate into filled droplets or hollowed condensate. Using hyperspectral stimulated Raman spectroscopy, we show that RNA coacervation is accompanied by the stacking and clustering of nucleobases, while forfeiting the canonical base-paired structure. At an increasing RNA/Mg2+ ratio, the RNA droplets first expand in sizes, and then shrink and adopt hollow vesicle-like structures. Significantly, for both large and vesicle-like droplets, the nucleobase-clustered structure is more prominent at the rim than at the center, accounting for the rigidification of RNA droplets. Thus, our finding has broad implications for the general aging processes of RNA-containing membrane-less organelles.

biochemistry↗

Delineating the genetic regulation of cannabinoid biosynthesis during female flower development in Cannabis sativa

O_LICannabinoids are predominantly produced in the glandular trichomes on cannabis female flowers. There is little known on how cannabinoid biosynthesis is regulated during female flower development. We aim to understand the rate-limiting step(s) in the cannabinoid biosynthetic pathway. C_LIO_LIWe investigated the transcript levels of cannabinoid biosynthetic genes as well as cannabinoid contents during 7 weeks of female flower development. We demonstrated that the enzymatic steps for producing CBG, which involve genes GPPS, PT and OAC, could be rate limit cannabinoid biosynthesis. Our findings further suggest that cannabinoid synthases, CBDAS and THCAS in a hemp and medical marijuana variety respectively, are not critical for cannabinoid biosynthesis. The cannabinoid biosynthetic genes are generally upregulated during flower maturation, which indicate glandular trichome development. C_LIO_LIMeJA can potentially increase cannabinoid production. We propose that biweekly application of 100 M MeJA staring from flower initiation would be efficacious for promoting cannabinoid biosynthesis. C_LIO_LIOur findings suggest that the step of CBG production could rate limit the terminal cannabinoid biosynthesis. In addition, different cannabis varieties demonstrated discrete transcriptional regulation of cannabinoid biosynthetic genes. C_LI

plant biology↗

An Immunogold Single Extracellular Vesicular RNA and Protein (AuSERP) Biochip to Predict Responses to Immunotherapy in Non-Small Cell Lung Cancer Patients

Conventional PD-L1 immunohistochemical tissue biopsies only predict 20~40% of non-small cell lung cancer (NSCLC) patients that will respond positively to anti-PD-1/PD-L1 immunotherapy. Herein, we present an immunogold biochip to quantify single extracellular vesicular RNA and protein (AuSERP) as a non-invasive alternative. With only 3 L of serum, PD-1/PD-L1 proteins on the surface of extracellular vesicles (EVs) and EV PD-1/PD-L1 messenger RNA (mRNA) cargo were detected at a single-vesicle resolution and exceeded the sensitivities of ELISA and qRT-PCR by 1000 times. By testing a cohort of 27 non-responding and 27 responding NSCLC patients, AuSERP indicated that the single-EV mRNA biomarkers surpass the single-EV protein biomarkers at predicting patient responses to immunotherapy. Dual single-EV PD-1/PD-L1 mRNA detection differentiated responders from non-responders with an accuracy of 72.2% and achieved an NSCLC diagnosis accuracy of 93.2%, suggesting the potential for AuSERP to provide enhanced immunotherapy predictions and cancer diagnoses within the clinical setting.

immunology↗

Spatiotemporal mapping of gene expression landscapes and developmental trajectories during zebrafish embryogenesis

Vertebrate embryogenesis is a remarkably dynamic process during which numerous cell types of different lineages generate, change, or disappear within a short period of time. A major challenge in understanding this process is the lack of topographical transcriptomic information that can help correlate microenvironmental cues within the hierarchy of cell fate decisions. Here, we employed Stereo-seq, a high-definition spatially resolved transcriptomic technology, to dissect the spatiotemporal dynamics of gene expression and regulatory networks in the developing zebrafish embryos. We profiled 91 embryo sections covering six critical time points during the first 24 hours of development, obtaining a total of 139,391 spots at cellular size ([~]100 m2) with spatial coordinates. Meanwhile, we identified spatial modules and co-varying genes for specific tissue organizations. By performing the integrative analysis of the Stereo-seq and scRNA-seq data from each time point, we reconstructed the spatially resolved developmental trajectories of cell fate transitions and molecular changes during zebrafish embryogenesis. We further investigated the spatial distribution of ligand-receptor pairs for major signaling pathways and identified novel interactions that potentially crosstalk with the Notch signaling pathway during zebrafish development. Our study constitutes a fundamental reference for further studies aiming to understand vertebrate development.

developmental biology↗

High Resolution Nanostructure with Two-stages of Exponential Energy Dissipation at the Ultrathin Osteochondral Interface Tissue of Human Knee Joint

Cartilage adheres to subchondral bone via a specific osteochondral interface tissue where forces are transferred from soft cartilage to hard bone without fatigue damage over a lifetime of load cycles. However, the fine structure and mechanical properties of osteochondral interface tissue remain unclear. Here, we identified an ultrathin [~]20-30 m calcified region with two-layered micro-nano structures of osteochondral interface tissue in human knee joint, which exhibited characteristic biomolecular compositions and complex nanocrystals assembly. Within this region, an exponential increase of modulus (3 orders of magnitude) was conducive to the force transmission which was verified by finite element simulations. The nanoscale heterogeneity of hydroxyapatite, along with enrichment of elastic-responsive protein-titin which is usually present in muscle, endowed the osteochondral tissue with excellent energy dissipation and fatigue resistance properties. Our results provide potential design for high-performance interface materials for osteochondral interface regeneration and functional coatings.

bioengineering↗

Type IV pilus shapes a "bubble-jet" pattern opposing spatial intermixing of two interacting bacterial populations

Microbes are social organisms that commonly live in sessile biofilms. Spatial patterns of populations within biofilms can be an important determinant of community-level properties. The best-studied characteristics of spatial patterns is spatial intermixing of different populations. The specific levels of spatial intermixing critically contribute to how the dynamics and functioning of such communities are governed. However, the precise factors that determine spatial patterns and intermixing remain unclear. Here, we investigated the spatial patterning and intermixing of an engineered synthetic consortium composed of two Pseudomonas stutzeri strains that degrade salicylate via metabolic cross-feeding. We found that the consortium self-organizes across space to form a previously unreported spatial pattern (referred to here as a bubble-jet pattern) that exhibits a low level of intermixing. Interestingly, when the genes encoding for type IV pili were deleted from both strains, a highly intermixed spatial pattern developed and increased the productivity of the entire community. The intermixed pattern was maintained in a robust manner across a wide range of initial ratios between the two strains. Our findings show that the type IV pilus plays a role in mitigating spatial intermixing of different populations in surface-attached microbial communities, with consequences for governing community-level properties. These insights provide tangible clues for the engineering of synthetic microbial systems that perform highly in spatially structured environments. ImportanceWhen growing on surfaces, multi-species microbial communities form biofilms that exhibit intriguing spatial patterns. These patterns can significantly affect the overall properties of the community, such as enabling otherwise impermissible metabolic functions to occur, as well as driving the evolutionary and ecological processes acting on communities. The development of these patterns is affected by several drivers, including cell-cell interactions, nutrient levels, density of founding cells and surface properties. The type IV pilus is commonly found to mediate surface-associated behaviors of microorganism, but its role on pattern formation within microbial communities is unclear. Here we report that in a cross-feeding consortium, the type IV pilus affects the spatial intermixing of interacting populations involved in pattern formation, and ultimately influences overall community productivity and robustness. This novel insight assists our understanding of the ecological processes of surface-attached microbial communities and suggests a potential strategy to engineer high-performance synthetic microbial communities.

microbiology↗

A new Mendelian Randomization method to estimate causal effects of multivariable brain imaging exposures

The advent of simultaneously collected imaging-genetics data in large study cohorts provides an unprecedented opportunity to assess the causal effect of brain imaging traits on externally measured experimental results (e.g., cognitive tests) by treating genetic variants as instrumental variables. However, classic Mendelian Randomization methods are limited when handling high-throughput imaging traits as exposures to identify causal effects. We propose a new Mendelian Randomization framework to jointly select instrumental variables and imaging exposures, and then estimate the causal effect of multivariable imaging data on the outcome. We validate the proposed method with extensive data analyses and compare it with existing methods. We further apply our method to evaluate the causal effect of white matter microstructure integrity on cognitive function. The findings suggest that our method achieved better performance regarding sensitivity, bias, and false discovery rate compared to individually assessing the causal effect of a single exposure and jointly assessing the causal effect of multiple exposures without dimension reduction. Our application results indicated that WM measures across different tracts have a joint causal effect that significantly impacts the cognitive function among the participants from the UK Biobank.

bioinformatics↗

Metformin modulates microbiota-derived inosine and ameliorates methamphetamine-induced anxiety and depression-like withdrawal symptoms in mice

ObjectiveMetformin exhibits therapeutic potential in behavioural deficits induced by methamphetamine (METH) in rats. Emerging studies suggest gut microbiota may impact psychiatric symptoms, but there is no direct evidence supporting metformins participation in the pathophysiology of withdrawal symptoms via modulation of gut microbiota. MehodsIn order to define the functional contributions by gut microbiota and metformin to the behavioural deficits during METH withdrawal, we utilized a combination of fecal microbiota transplantation (FMT), high-throughput sequencing, and untargeted metabolomics technologies. ResultsFirst, METH addicts exhibited higher diversity and distinct microbial structures compared to heathy controls. In particular, the relative abundance of Rikenellaceae was positively correlated with the severity of anxiety and depression. Second, both human-to-mouse and mouse-to-mouse FMTs confirmed that METH-altered-microbiota transplantation is sufficient to promote anxiety and depression-like behaviours in recipient germ-free mice, and these behavioural disturbances could be ameliorated by metformin. In-depth analysis revealed that METH significantly altered the bacterial composition and structure as well as relative abundance of several bacterial taxa and metabolites, including Rikenellaceae and inosine, respectively, whereas add-on metformin could remodel these alterations. Finally, the inosine complementation successfully restored METH-induced anxiety and depression-like behaviours in mice. DiscussionThis study demonstrates that METH withdrawal-induced anxiety and depression-like behaviours are convertible and transmissible via gut microbiota in a mouse model. The therapeutic effects of metformin on psychiatric manifestations are associated with microbiota-derived metabolites, highlighting the role of the gut microbiota in substance use disorders and the pathophysiology of withdrawal symptoms. Study HighlightsO_ST_ABSWhat is known?C_ST_ABSO_LIThere are no targeted therapies for substance withdrawal syndrome, but there is considerable evidence that withdrawal-associated psychiatric manifestations contribute to the poor adherence to rehabilitation treatment as well as the relapse rates. C_LIO_LIMetformin has shown its therapeutic potential against METH-induced neurobehavioural changes and neurodegeneration in rats through CREB/BDNF and Akt/GSK3 signaling pathways in the anxiety-related brain nuclei. C_LI What is new here?O_LIMETH withdrawal-induced anxiety and depression-like behaviours are convertible and transmissible via gut microbiota in a mouse model. C_LIO_LIThe therapeutic effects of metformin on psychiatric manifestations are associated with microbiota derived metabolites. C_LIO_LIInosine complementation could restore METH withdrawal-induced anxiety and depression-like behaviours. C_LI

animal behavior and cognition↗

Accurate Name Entity Recognition for Biomedical Literatures: A Combined High-quality Manual Annotation and Deep-learning Natural Language Processing Study

A combined high-quality manual annotation and deep-learning natural language processing study is reported to make accurate name entity recognition (NER) for biomedical literatures. A home-made version of entity annotation guidelines on biomedical literatures was constructed. Our manual annotations have an overall over 92% consistency for all the four entity types -- gene, variant, disease and species --with the same publicly available annotated corpora from other experts previously. A total of 400 full biomedical articles from PubMed are annotated based on our home-made entity annotation guidelines. Both a BERT-based large model and a DistilBERT-based simplified model were constructed, trained and optimized for offline and online inference, respectively. The F1-scores of NER of gene, variant, disease and species for the BERT-based model are 97.28%, 93.52%, 92.54% and 95.76%, respectively, while those for the DistilBERT-based model are 95.14%, 86.26%, 91.37% and 89.92%, respectively. The F1 scores of the DistilBERT-based NER model retains 97.8%, 92.2%, 98.7% and 93.9% of those of BERT-based NER for gene, variant, disease and species, respectively. Moreover, the performance for both our BERT-based NER model and DistilBERT-based NER model outperforms that of the state-of-art model--BioBERT, indicating the significance to train an NER model on biomedical-domain literatures jointly with high-quality annotated datasets.

bioinformatics↗

GMQN: A reference-based method for correcting batch effects as well as probes bias in HumanMethylation BeadChip

Illumina HumanMethylation BeadChip is one of the most cost-effective ways to quantify DNA methylation levels at the single-base level across the human genome, which makes it a routine platform for epigenome-wide association studies. It has accumulated tens of thousands of DNA methylation array samples in public databases, thus provide great support for data integration and further analysis. However, majority of public DNA methylation data are deposited as processed data without background probes which are widely used in data normalization. Here we present Gaussian mixture quantile normalization (GMQN), a reference based method for correcting batch effects as well as probes bias in HumanMethylation BeadChip. Availability and implementation: https://github.com/MengweiLi-project/gmqn.

bioinformatics↗