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Ruan, F.

Publications and source records attributed to Ruan, F..

9 recordsLinked to original sources

MatClassRSA v2 release: A MATLAB toolbox for M/EEG classification, proximity matrix construction, and visualization

MatClassRSA is a MATLAB toolbox that performs magnetoen-cephalography and electroencephalography (M/EEG) classification and other analyses related to Representational Similarity Analysis (RSA). The toolbox is designed for cognitive neuroscience researchers who wish to perform classification-based decoding analyses of their data--often repeated trials of evoked responses--or derive Representational Dissimilarity Matrices (RDMs) as input to RSA. Organized as a collection of usercalled functions, MatClassRSA v2 comprises five main modules: Preprocessing, Reliability, Classification, RDM Computation, and Visualization. The Classification module supports multiple classifiers (LDA, RF, SVM) and classification schemes (e.g., multiclass, pairwise, cross-validated, train-test, hyperparameter optimization) and offers basic statistical analyses via permutation testing. Functions in other modules include, for example, trial-averaging and noise normalization; reliability estimation; non-classification RDM construction; and hierarchical and non-hierarchical clustering visualizations. The toolbox is freely available on GitHub under an MIT license and includes the main codebase, a User Manual, example function calls, and illustrative analyses. This preprint provides a general background of M/EEG classification for RSA as well as a narrative overview of the v2 MatClassRSA release, its updated functionalities, and illustrative analyses performed using the toolbox.

neuroscience↗

High efficient chromatin conformation capture without pre-enrichment (HiChew) in single cells

This study presents HiChew, a cutting-edge technique for high-efficiency chromatin conformation capture in single cells, without the need for pre-enrichment. This unique approach minimizes the risk of cell or DNA loss. When compared to Dip-C, HiChew captures valid pairs with 4-8 times more efficiency, reducing wastage and saving significant sequencing budget. Furthermore, HiChew delivers a lower false positive ratio, ensuring data accuracy. It also achieves more contacts per cell, enhancing resolution in single cell. HiChews superior performance not only enhances single-cell Hi-C but also streamlines conventional Hi-C, making it more robust than conventional HiC methods. This study also unveils a fascinating mechanism of gene activation in the B compartment of chromatin, providing insight into the elusive aspect of gene expression within this region.

genomics↗

NLSDeconv: an efficient cell-type deconvolution method for spatial transcriptomics data

SummarySpatial transcriptomics (ST) allows gene expression profiling within intact tissue samples but lacks single-cell resolution. This necessitates computational deconvolution methods to estimate the contributions of distinct cell types. This paper introduces NLSDeconv, a novel cell-type deconvolution method based on non-negative least squares, along with an accompanying Python package. Benchmarking against 18 existing deconvolution methods on various ST datasets demonstrates NLSDeconvs competitive statistical performance and superior computational efficiency. Availability and implementationNLSDeconv is freely available with tutorial at https://github.com/tinachentc/NLSDeconv as a Python package.

genomics↗

Multi-omics map revealed PPARalpha activation protecting against myocardial ischemia-reperfusion injury by maintaining cardiac metabolic homeostasis

Timely percutaneous coronary intervention is the most effective initial therapy for the acute myocardial infarction (MI). However, the mechanism in energy metabolism underlying time-dependent coronary reperfusion remains largely unknown. Here, we generated an integrative map of cardiac cells using bulk and single-nucleus RNA-seq combined with metabolomics profiling of hearts with reperfusion at distinct time points post MI in rat. We found early time reperfusion (ETR), but not late time reperfusion (LTR) reduced myocardial injury by maintaining cardiac energy homeostasis. PPAR was identified as a key regulator for maintaining fatty acid metabolism after MI/R injury. Importantly, pretreatment with FDA-approved PPAR agonist, fenofibrate, improved the transcriptional signatures, and ameliorated the function of the MI/R injured hearts, particularly in the ETR. Together, our data not only deciphered the protective effect of ETR by maintaining cardiac energy homeostasis, but also provided insights into the translational potential of PPAR activation in alleviating MI/R injury.

cell biology↗

Spatial chromatin accessibility sequencing resolves next-generation genome architecture

As the genome is organized into a three-dimensional structure in intracellular space, epigenomic information also has a complex spatial arrangement. However, most epigenetic studies describe locations of methylation marks, chromatin accessibility regions, and histone modifications in the horizontal dimension. Proper spatial epigenomic information has rarely been obtained. In this study, we designed spatial chromatin accessibility sequencing (SCA-seq) to resolve the genome conformation by capturing the epigenetic information in single-molecular resolution while simultaneously resolving the genome conformation. Using SCA-seq, we are able to examine the spatial interaction of chromatin accessibility (e.g. enhancer-promoter contacts), CpG island methylation, and spatial insulating functions of the CCCTC-binding factor. We demonstrate that SCA-seq paves the way to explore the mechanism of epigenetic interactions and extends our knowledge in 3D packaging of DNA in the nucleus.

genomics↗

High coverage of single cell genomes by T7-assisted enzymatic methyl-sequencing

Conventional approaches to studying 5mC marks in single cells or samples with picogram input DNA amounts usually suffer from low genome coverage due to DNA degradation. Many methods have been developed to optimize the library construction efficiency for bisulfite-treated DNA. However, most of these approaches ignored the amplification bias of bisulfite-treated DNA, which leads to shallow genome coverage. In this study, we developed the T7-assisted enzymatic methyl-sequencing method (TEAM-seq), which adopts enzymatic conversion to minimize DNA degradation and T7 polymerase-assisted unbiased amplification. We demonstrate that TEAM-seq delivered, to the best of our knowledge, the highest reported coverage(70% for 100pg, 35% for 20pg) of single cell genomes in whole-genome 5mC sequencing.

genomics↗

Long-range single-molecule mapping of chromatin modification in eukaryotes

The epigenetic modifications of histones are essential markers related to the development and pathogenesis of diseases, including human cancers. Mapping histone modification has emerged as the widely used tool for studying epigenetic regulation. However, existing approaches are limited by fragmentation and short-read sequencing represent the average chromatin status in samples and cannot provide information about the long-range chromatin states. We leveraged the advantage of long read sequencing to develop a method "BIND&MODIFY" for profiling the histone modification of individual DNA fibers. Our approach is based on the recombinant fused protein A-M.EcoGII, which tethers the methyltransferase M.EcoGII to the protein binding sites and locally labels the neighboring DNA regions through artificial methylations. We demonstrated that the aggregated BIND&MODIFY signal matches the bulk-level ChIP-seq and CUT&TAG, verify the single-molecule heterogenous histone modification status, and quantify the correlation between distal elements. This method could be an essential tool in future third-generation sequencing ages.

genomics↗

CDCA-seq resolve the different chromatin structure on integral circular DNAs

Although extrachromosomal DNA (ecDNA) has been intensively studied for several decades, the mechanisms underlying its tumorigenic effects have been revealed only recently. In the majority of conventional sequencing studies, the high-throughput short-read sequencing largely ignores the epigenetic status of most ecDNA regions except for the junctional areas. Here, we developed the sequencing of enzyme-accessible chromatin in circular DNA (CCDA-seq) method, which uses methylase to label open chromatin without fragmentation and exonuclease to enrich the ecDNA sequencing depth, followed by long-read nanopore sequencing. Using CCDA-seq, we observed significantly different patterns in nucleosome/regulator binding in ecDNA at a single-molecule resolution. These results deepen the understanding of ecDNA regulatory mechanisms.

genomics↗

miRNA-dependent poly(A) length control in uncoupling transcription and translation of haploid male germ cells

As one of the post-transcriptional regulatory mechanisms, transcription and translations uncoupling plays an essential role in development and adulthood physiology. However, it remains elusive how thousands of mRNAs get translationally silenced while stability is maintained for up to hours or even days before translation. In addition to oocytes and neurons, developing spermatids have significant uncoupling of transcription and translation for delayed translation. Therefore, spermiogenesis represents an excellent in vivo model for investigating the mechanism underlying uncoupled transcription and translation. Through full-length poly(A) deep sequencing, we discovered dynamic changes in poly(A) length through deadenylation and re-polyadenylation. Deadenylation appeared to be mediated by microRNAs (miRNAs), and transcripts with shorter poly(A) tails tend to be sequestered into ribonucleoproteins (RNPs) for translational repression and stabilization. In contrast, re-polyadenylation allows for translocation of the translationally repressed transcripts from RNPs to polysomes for translation. Overall, our data suggest that miRNA-dependent poly(A) length control represents a novel mechanism underlying uncoupled translation and transcription in haploid male germ cells.

molecular biology↗