51
|
Chen J, Cheong C, Lan L, Zhou X, Liu J, Lyu A, Cheung WK, Zhang L. DeepDRIM: a deep neural network to reconstruct cell-type-specific gene regulatory network using single-cell RNA-seq data. Brief Bioinform 2021; 22:bbab325. [PMID: 34424948 PMCID: PMC8499812 DOI: 10.1093/bib/bbab325] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/12/2021] [Accepted: 07/26/2021] [Indexed: 01/11/2023] Open
Abstract
Single-cell RNA sequencing has enabled to capture the gene activities at single-cell resolution, thus allowing reconstruction of cell-type-specific gene regulatory networks (GRNs). The available algorithms for reconstructing GRNs are commonly designed for bulk RNA-seq data, and few of them are applicable to analyze scRNA-seq data by dealing with the dropout events and cellular heterogeneity. In this paper, we represent the joint gene expression distribution of a gene pair as an image and propose a novel supervised deep neural network called DeepDRIM which utilizes the image of the target TF-gene pair and the ones of the potential neighbors to reconstruct GRN from scRNA-seq data. Due to the consideration of TF-gene pair's neighborhood context, DeepDRIM can effectively eliminate the false positives caused by transitive gene-gene interactions. We compared DeepDRIM with nine GRN reconstruction algorithms designed for either bulk or single-cell RNA-seq data. It achieves evidently better performance for the scRNA-seq data collected from eight cell lines. The simulated data show that DeepDRIM is robust to the dropout rate, the cell number and the size of the training data. We further applied DeepDRIM to the scRNA-seq gene expression of B cells from the bronchoalveolar lavage fluid of the patients with mild and severe coronavirus disease 2019. We focused on the cell-type-specific GRN alteration and observed targets of TFs that were differentially expressed between the two statuses to be enriched in lysosome, apoptosis, response to decreased oxygen level and microtubule, which had been proved to be associated with coronavirus infection.
Collapse
Affiliation(s)
- Jiaxing Chen
- Department of Computer Science, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| | - ChinWang Cheong
- Department of Computer Science, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| | - Liang Lan
- Department of Computer Science, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| | - Xin Zhou
- Department of Biomedical Engineering, Vanderbilt University, Vanderbilt Place Nashville, 37235, TN, USA
| | - Jiming Liu
- Department of Computer Science, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| | - Aiping Lyu
- School of Chinese Medicine, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| | - William K Cheung
- Department of Computer Science, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| | - Lu Zhang
- Department of Computer Science, Hong Kong Baptist University, Waterloo Road, Kowloon Tong, Hong Kong
| |
Collapse
|
52
|
Raharinirina NA, Peppert F, von Kleist M, Schütte C, Sunkara V. Inferring gene regulatory networks from single-cell RNA-seq temporal snapshot data requires higher-order moments. PATTERNS 2021; 2:100332. [PMID: 34553172 PMCID: PMC8441581 DOI: 10.1016/j.patter.2021.100332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 02/23/2021] [Accepted: 07/22/2021] [Indexed: 11/30/2022]
Abstract
Single-cell RNA sequencing (scRNA-seq) has become ubiquitous in biology. Recently, there has been a push for using scRNA-seq snapshot data to infer the underlying gene regulatory networks (GRNs) steering cellular function. To date, this aspiration remains unrealized due to technical and computational challenges. In this work we focus on the latter, which is under-represented in the literature. We took a systemic approach by subdividing the GRN inference into three fundamental components: data pre-processing, feature extraction, and inference. We observed that the regulatory signature is captured in the statistical moments of scRNA-seq data and requires computationally intensive minimization solvers to extract it. Furthermore, current data pre-processing might not conserve these statistical moments. Although our moment-based approach is a didactic tool for understanding the different compartments of GRN inference, this line of thinking—finding computationally feasible multi-dimensional statistics of data—is imperative for designing GRN inference methods. Single-cell RNA-seq temporal snapshot data for detecting regulation Challenges in data pre-processing, feature extraction, and network inference for GRNs Encoding of regulatory information in higher-order raw moments Non-linear least-squares inference for temporal scRNA-seq snapshot data
Single-cell RNA sequencing (scRNA-seq) has become ubiquitous in biology. Recently, there has been a push for using scRNA-seq snapshot data to infer the underlying gene regulatory networks (GRNs) steering cellular function. A recent benchmark of 12 GRN methods demonstrated that the algorithms struggled to predict the ground-truth GRNs and speculated that the low performance was due to the insufficient resolution in the scRNA-seq data. Rather than proposing another method, this paper focuses on how to decompose a GRN problem into three subproblems (pre-processing, feature extraction, and inference), so that the gene regulatory information is preserved in each step. Subsequently, we discuss how to best approach each of the three subproblems.
Collapse
Affiliation(s)
| | - Felix Peppert
- Explainable A.I. for Biology, Zuse Institute Berlin, 14195 Berlin, Germany
| | - Max von Kleist
- MF1 Bioinformatics, Methods Development and Research Infrastructure, Robert Koch Institute, 13353 Berlin, Germany
| | - Christof Schütte
- Mathematics of Complex Systems, Zuse Institute Berlin, 14195 Berlin, Germany.,Department of Mathematics and Computer Science, Freie Universität Berlin, 14195 Berlin, Germany
| | - Vikram Sunkara
- Mathematics of Complex Systems, Zuse Institute Berlin, 14195 Berlin, Germany.,Explainable A.I. for Biology, Zuse Institute Berlin, 14195 Berlin, Germany
| |
Collapse
|
53
|
Srinivasan A, Bain M, Baskar A. Learning explanations for biological feedback with delays using an event calculus. Mach Learn 2021. [DOI: 10.1007/s10994-021-06038-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
54
|
The early Drosophila embryo as a model system for quantitative biology. Cells Dev 2021; 168:203722. [PMID: 34298230 DOI: 10.1016/j.cdev.2021.203722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/03/2021] [Accepted: 07/13/2021] [Indexed: 11/20/2022]
Abstract
With the rise of new tools, from controlled genetic manipulations and optogenetics to improved microscopy, it is now possible to make clear, quantitative and reproducible measurements of biological processes. The humble fruit fly Drosophila melanogaster, with its ease of genetic manipulation combined with excellent imaging accessibility, has become a major model system for performing quantitative in vivo measurements. Such measurements are driving a new wave of interest from physicists and engineers, who are developing a range of testable dynamic models of active systems to understand fundamental biological processes. The reproducibility of the early Drosophila embryo has been crucial for understanding how biological systems are robust to unavoidable noise during development. Insights from quantitative in vivo experiments in the Drosophila embryo are having an impact on our understanding of critical biological processes, such as how cells make decisions and how complex tissue shape emerges. Here, to highlight the power of using Drosophila embryogenesis for quantitative biology, I focus on three main areas: (1) formation and robustness of morphogen gradients; (2) how gene regulatory networks ensure precise boundary formation; and (3) how mechanical interactions drive packing and tissue folding. I further discuss how such data has driven advances in modelling.
Collapse
|
55
|
Grimes T, Datta S. SeqNet: An R Package for Generating Gene-Gene Networks and Simulating RNA-Seq Data. J Stat Softw 2021; 98:10.18637/jss.v098.i12. [PMID: 34321962 PMCID: PMC8315007 DOI: 10.18637/jss.v098.i12] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Gene expression data provide an abundant resource for inferring connections in gene regulatory networks. While methodologies developed for this task have shown success, a challenge remains in comparing the performance among methods. Gold-standard datasets are scarce and limited in use. And while tools for simulating expression data are available, they are not designed to resemble the data obtained from RNA-seq experiments. SeqNet is an R package that provides tools for generating a rich variety of gene network structures and simulating RNA-seq data from them. This produces in silico RNA-seq data for benchmarking and assessing gene network inference methods. The package is available on CRAN and on GitHub at https://github.com/tgrimes/SeqNet.
Collapse
Affiliation(s)
- Tyler Grimes
- Univeristy of Florida, Department of Biostatistics
| | | |
Collapse
|
56
|
Alvarez JM, Brooks MD, Swift J, Coruzzi GM. Time-Based Systems Biology Approaches to Capture and Model Dynamic Gene Regulatory Networks. ANNUAL REVIEW OF PLANT BIOLOGY 2021; 72:105-131. [PMID: 33667112 PMCID: PMC9312366 DOI: 10.1146/annurev-arplant-081320-090914] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
All aspects of transcription and its regulation involve dynamic events. However, capturing these dynamic events in gene regulatory networks (GRNs) offers both a promise and a challenge. The promise is that capturing and modeling the dynamic changes in GRNs will allow us to understand how organisms adapt to a changing environment. The ability to mount a rapid transcriptional response to environmental changes is especially important in nonmotile organisms such as plants. The challenge is to capture these dynamic, genome-wide events and model them in GRNs. In this review, we cover recent progress in capturing dynamic interactions of transcription factors with their targets-at both the local and genome-wide levels-and how they are used to learn how GRNs operate as a function of time. We also discuss recent advances that employ time-based machine learning approaches to forecast gene expression at future time points, a key goal of systems biology.
Collapse
Affiliation(s)
- Jose M Alvarez
- Centro de Genómica y Bioinformática, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- ANID-Millennium Science Initiative Program-Millennium Institute for Integrative Biology (iBio), Santiago, Chile
| | - Matthew D Brooks
- Global Change and Photosynthesis Research Unit, US Department of Agriculture Agricultural Research Service, Urbana, Illinois 61801, USA
| | - Joseph Swift
- Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Gloria M Coruzzi
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY 10003, USA;
| |
Collapse
|
57
|
Mousavi R, Konuru SH, Lobo D. Inference of dynamic spatial GRN models with multi-GPU evolutionary computation. Brief Bioinform 2021; 22:6217729. [PMID: 33834216 DOI: 10.1093/bib/bbab104] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/15/2021] [Accepted: 03/09/2021] [Indexed: 02/06/2023] Open
Abstract
Reverse engineering mechanistic gene regulatory network (GRN) models with a specific dynamic spatial behavior is an inverse problem without analytical solutions in general. Instead, heuristic machine learning algorithms have been proposed to infer the structure and parameters of a system of equations able to recapitulate a given gene expression pattern. However, these algorithms are computationally intensive as they need to simulate millions of candidate models, which limits their applicability and requires high computational resources. Graphics processing unit (GPU) computing is an affordable alternative for accelerating large-scale scientific computation, yet no method is currently available to exploit GPU technology for the reverse engineering of mechanistic GRNs from spatial phenotypes. Here we present an efficient methodology to parallelize evolutionary algorithms using GPU computing for the inference of mechanistic GRNs that can develop a given gene expression pattern in a multicellular tissue area or cell culture. The proposed approach is based on multi-CPU threads running the lightweight crossover, mutation and selection operators and launching GPU kernels asynchronously. Kernels can run in parallel in a single or multiple GPUs and each kernel simulates and scores the error of a model using the thread parallelism of the GPU. We tested this methodology for the inference of spatiotemporal mechanistic gene regulatory networks (GRNs)-including topology and parameters-that can develop a given 2D gene expression pattern. The results show a 700-fold speedup with respect to a single CPU implementation. This approach can streamline the extraction of knowledge from biological and medical datasets and accelerate the automatic design of GRNs for synthetic biology applications.
Collapse
Affiliation(s)
- Reza Mousavi
- Department of Biological Sciences at the University of Maryland, Baltimore, MD 21250, USA
| | - Sri Harsha Konuru
- Department of Biological Sciences at the University of Maryland, Baltimore, MD 21250, USA
| | - Daniel Lobo
- Department of Biological Sciences at the University of Maryland, Baltimore, MD 21250, USA
| |
Collapse
|
58
|
Gene regulatory networks exhibit several kinds of memory: quantification of memory in biological and random transcriptional networks. iScience 2021; 24:102131. [PMID: 33748699 PMCID: PMC7970124 DOI: 10.1016/j.isci.2021.102131] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/09/2020] [Accepted: 01/26/2021] [Indexed: 02/08/2023] Open
Abstract
Gene regulatory networks (GRNs) process important information in developmental biology and biomedicine. A key knowledge gap concerns how their responses change over time. Hypothesizing long-term changes of dynamics induced by transient prior events, we created a computational framework for defining and identifying diverse types of memory in candidate GRNs. We show that GRNs from a wide range of model systems are predicted to possess several types of memory, including Pavlovian conditioning. Associative memory offers an alternative strategy for the biomedical use of powerful drugs with undesirable side effects, and a novel approach to understanding the variability and time-dependent changes of drug action. We find evidence of natural selection favoring GRN memory. Vertebrate GRNs overall exhibit more memory than invertebrate GRNs, and memory is most prevalent in differentiated metazoan cell networks compared with undifferentiated cells. Timed stimuli are a powerful alternative for biomedical control of complex in vivo dynamics without genomic editing or transgenes. Gene regulatory networks' dynamics are modified by transient stimuli GRNs have several different types of memory, including associative conditioning Evolution favored GRN memory, and differentiated cells have the most memory capacity Training GRNs offers a novel biomedical strategy not dependent on genetic rewiring
Collapse
|
59
|
Vundavilli H, Datta A, Sima C, Hua J, Lopes R, Bittner M. Targeting oncogenic mutations in colorectal cancer using cryptotanshinone. PLoS One 2021; 16:e0247190. [PMID: 33596259 PMCID: PMC7888617 DOI: 10.1371/journal.pone.0247190] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/02/2021] [Indexed: 12/12/2022] Open
Abstract
Colorectal cancer (CRC) is one of the most prevalent types of cancer in the world and ranks second in cancer deaths in the US. Despite the recent improvements in screening and treatment, the number of deaths associated with CRC is still very significant. The complexities involved in CRC therapy stem from multiple oncogenic mutations and crosstalk between abnormal pathways. This calls for using advanced molecular genetics to understand the underlying pathway interactions responsible for this cancer. In this paper, we construct the CRC pathway from the literature and using an existing public dataset on healthy vs tumor colon cells, we identify the genes and pathways that are mutated and are possibly responsible for the disease progression. We then introduce drugs in the CRC pathway, and using a boolean modeling technique, we deduce the drug combinations that produce maximum cell death. Our theoretical simulations demonstrate the effectiveness of Cryptotanshinone, a traditional Chinese herb derivative, achieved by targeting critical oncogenic mutations and enhancing cell death. Finally, we validate our theoretical results using wet lab experiments on HT29 and HCT116 human colorectal carcinoma cell lines.
Collapse
Affiliation(s)
- Haswanth Vundavilli
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas, United States of America
- TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering (CBGSE), College Station, Texas, United States of America
| | - Aniruddha Datta
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas, United States of America
- TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering (CBGSE), College Station, Texas, United States of America
| | - Chao Sima
- TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering (CBGSE), College Station, Texas, United States of America
| | - Jianping Hua
- TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering (CBGSE), College Station, Texas, United States of America
| | - Rosana Lopes
- TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering (CBGSE), College Station, Texas, United States of America
| | - Michael Bittner
- TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering (CBGSE), College Station, Texas, United States of America
| |
Collapse
|
60
|
Mishra A, Khanal R, Kabir WU, Hoque T. AIRBP: Accurate identification of RNA-binding proteins using machine learning techniques. Artif Intell Med 2021; 113:102034. [PMID: 33685590 DOI: 10.1016/j.artmed.2021.102034] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 01/19/2021] [Accepted: 02/09/2021] [Indexed: 12/25/2022]
Abstract
Identification of RNA-binding proteins (RBPs) that bind to ribonucleic acid molecules is an important problem in Computational Biology and Bioinformatics. It becomes indispensable to identify RBPs as they play crucial roles in post-transcriptional control of RNAs and RNA metabolism as well as have diverse roles in various biological processes such as splicing, mRNA stabilization, mRNA localization, and translation, RNA synthesis, folding-unfolding, modification, processing, and degradation. The existing experimental techniques for identifying RBPs are time-consuming and expensive. Therefore, identifying RBPs directly from the sequence using computational methods can be useful to annotate RBPs and assist the experimental design efficiently. In this work, we present a method called AIRBP, which is designed using an advanced machine learning technique, called stacking, to effectively predict RBPs by utilizing features extracted from evolutionary information, physiochemical properties, and disordered properties. Moreover, our method, AIRBP, use the majority vote from RBPPred, DeepRBPPred, and the stacking model for the prediction for RBPs. The results show that AIRBP attains Accuracy (ACC), Balanced Accuracy (BACC), F1-score, and Mathews Correlation Coefficient (MCC) of 95.84 %, 94.71 %, 0.928, and 0.899, respectively, based on the training dataset, using 10-fold cross-validation (CV). Further evaluation of AIRBP on independent test set reveals that it achieves ACC, BACC, F1-score, and MCC of 94.36 %, 94.28 %, 0.897, and 0.860, for Human test set; 91.25 %, 93.00 %, 0.896, and 0.835 for S. cerevisiae test set; and 90.60 %, 90.41 %, 0.934, and 0.775 for A. thaliana test set, respectively. These results indicate that the AIRBP outperforms the existing Deep- and TriPepSVM methods. Therefore, the proposed better-performing AIRBP can be useful for accurate identification and annotation of RBPs directly from the sequence and help gain valuable insight to treat critical diseases. Availability: Code-data is available here: http://cs.uno.edu/∼tamjid/Software/AIRBP/code_data.zip.
Collapse
Affiliation(s)
- Avdesh Mishra
- Department of Electrical Engineering and Computer Science, Texas A&M University-Kingsville, Kingsville, TX, USA
| | - Reecha Khanal
- Department of Computer Science, University of New Orleans, New Orleans, LA, USA
| | - Wasi Ul Kabir
- Department of Computer Science, University of New Orleans, New Orleans, LA, USA
| | - Tamjidul Hoque
- Department of Computer Science, University of New Orleans, New Orleans, LA, USA.
| |
Collapse
|
61
|
Ingham VA, Elg S, Nagi SC, Dondelinger F. Capturing the transcription factor interactome in response to sub-lethal insecticide exposure. CURRENT RESEARCH IN INSECT SCIENCE 2021; 1:None. [PMID: 34977825 PMCID: PMC8702396 DOI: 10.1016/j.cris.2021.100018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 06/15/2021] [Accepted: 07/21/2021] [Indexed: 12/02/2022]
Abstract
The increasing levels of pesticide resistance in agricultural pests and disease vectors represents a threat to both food security and global health. As insecticide resistance intensity strengthens and spreads, the likelihood of a pest encountering a sub-lethal dose of pesticide dramatically increases. Here, we apply dynamic Bayesian networks to a transcriptome time-course generated using sub-lethal pyrethroid exposure on a highly resistant Anopheles coluzzii population. The model accounts for circadian rhythm and ageing effects allowing high confidence identification of transcription factors with key roles in pesticide response. The associations generated by this model show high concordance with lab-based validation and identifies 44 transcription factors putatively regulating insecticide-responsive transcripts. We identify six key regulators, with each displaying differing enrichment terms, demonstrating the complexity of pesticide response. The considerable overlap of resistance mechanisms in agricultural pests and disease vectors strongly suggests that these findings are relevant in a wide variety of pest species.
Collapse
|
62
|
Hütt MT, Lesne A. Gene Regulatory Networks: Dissecting Structure and Dynamics. SYSTEMS MEDICINE 2021. [DOI: 10.1016/b978-0-12-801238-3.11467-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
|
63
|
Zaborowski AB, Walther D. Determinants of correlated expression of transcription factors and their target genes. Nucleic Acids Res 2020; 48:11347-11369. [PMID: 33104784 PMCID: PMC7672440 DOI: 10.1093/nar/gkaa927] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 10/01/2020] [Accepted: 10/06/2020] [Indexed: 11/14/2022] Open
Abstract
While transcription factors (TFs) are known to regulate the expression of their target genes (TGs), only a weak correlation of expression between TFs and their TGs has generally been observed. As lack of correlation could be caused by additional layers of regulation, the overall correlation distribution may hide the presence of a subset of regulatory TF-TG pairs with tight expression coupling. Using reported regulatory pairs in the plant Arabidopsis thaliana along with comprehensive gene expression information and testing a wide array of molecular features, we aimed to discern the molecular determinants of high expression correlation of TFs and their TGs. TF-family assignment, stress-response process involvement, short genomic distances of the TF-binding sites to the transcription start site of their TGs, few required protein-protein-interaction connections to establish physical interactions between the TF and polymerase-II, unambiguous TF-binding motifs, increased numbers of miRNA target-sites in TF-mRNAs, and a young evolutionary age of TGs were found particularly indicative of high TF-TG correlation. The modulating roles of post-transcriptional, post-translational processes, and epigenetic factors have been characterized as well. Our study reveals that regulatory pairs with high expression coupling are associated with specific molecular determinants.
Collapse
Affiliation(s)
- Adam B Zaborowski
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Dirk Walther
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| |
Collapse
|
64
|
Ajmal HB, Madden MG. Inferring dynamic gene regulatory networks with low-order conditional independencies – an evaluation of the method. Stat Appl Genet Mol Biol 2020. [DOI: 10.1515/sagmb-2020-0051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractOver a decade ago, Lèbre (2009) proposed an inference method, G1DBN, to learn the structure of gene regulatory networks (GRNs) from high dimensional, sparse time-series gene expression data. Their approach is based on concept of low-order conditional independence graphs that they extend to dynamic Bayesian networks (DBNs). They present results to demonstrate that their method yields better structural accuracy compared to the related Lasso and Shrinkage methods, particularly where the data is sparse, that is, the number of time measurements n is much smaller than the number of genes p. This paper challenges these claims using a careful experimental analysis, to show that the GRNs reverse engineered from time-series data using the G1DBN approach are less accurate than claimed by Lèbre (2009). We also show that the Lasso method yields higher structural accuracy for graphs learned from the simulated data, compared to the G1DBN method, particularly when the data is sparse ($n{< }{< }p$). The Lasso method is also better than G1DBN at identifying the transcription factors (TFs) involved in the cell cycle of Saccharomyces cerevisiae.
Collapse
Affiliation(s)
- Hamda B. Ajmal
- School of Computer Science, National University of Ireland, Galway, Ireland
| | - Michael G. Madden
- School of Computer Science, National University of Ireland, Galway, Ireland
| |
Collapse
|
65
|
Single-cell network biology for resolving cellular heterogeneity in human diseases. Exp Mol Med 2020; 52:1798-1808. [PMID: 33244151 PMCID: PMC8080824 DOI: 10.1038/s12276-020-00528-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/26/2020] [Accepted: 08/31/2020] [Indexed: 01/10/2023] Open
Abstract
Understanding cellular heterogeneity is the holy grail of biology and medicine. Cells harboring identical genomes show a wide variety of behaviors in multicellular organisms. Genetic circuits underlying cell-type identities will facilitate the understanding of the regulatory programs for differentiation and maintenance of distinct cellular states. Such a cell-type-specific gene network can be inferred from coregulatory patterns across individual cells. Conventional methods of transcriptome profiling using tissue samples provide only average signals of diverse cell types. Therefore, reconstructing gene regulatory networks for a particular cell type is not feasible with tissue-based transcriptome data. Recently, single-cell omics technology has emerged and enabled the capture of the transcriptomic landscape of every individual cell. Although single-cell gene expression studies have already opened up new avenues, network biology using single-cell transcriptome data will further accelerate our understanding of cellular heterogeneity. In this review, we provide an overview of single-cell network biology and summarize recent progress in method development for network inference from single-cell RNA sequencing (scRNA-seq) data. Then, we describe how cell-type-specific gene networks can be utilized to study regulatory programs specific to disease-associated cell types and cellular states. Moreover, with scRNA data, modeling personal or patient-specific gene networks is feasible. Therefore, we also introduce potential applications of single-cell network biology for precision medicine. We envision a rapid paradigm shift toward single-cell network analysis for systems biology in the near future. Gene regulatory networks reconstructed from single-cell RNA sequencing datasets are allowing researchers to better understand the molecular circuits and cell states that contribute to complex human disease. Junha Cha and Insuk Lee from Yonsei University in Seoul, South Korea, review the concept of ‘single-cell network biology’, which involves using computational algorithms on genetic expression data from thousands of cells to infer functional interactions in various biological contexts. This systems biology approach to analyzing the profiles of messenger RNA in single cells is helping researchers discover new signaling pathways that could serve as disease biomarkers or therapeutic targets. In the future, patient-specific models of personal gene networks could explain why certain genetic variants affect disease risk. This research could also eventually lead to new types of individualized medical treatments.
Collapse
|
66
|
Iliopoulos A, Beis G, Apostolou P, Papasotiriou I. Complex Networks, Gene Expression and Cancer Complexity: A Brief Review of Methodology and Applications. Curr Bioinform 2020. [DOI: 10.2174/1574893614666191017093504] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In this brief survey, various aspects of cancer complexity and how this complexity can
be confronted using modern complex networks’ theory and gene expression datasets, are described.
In particular, the causes and the basic features of cancer complexity, as well as the challenges
it brought are underlined, while the importance of gene expression data in cancer research
and in reverse engineering of gene co-expression networks is highlighted. In addition, an introduction
to the corresponding theoretical and mathematical framework of graph theory and complex
networks is provided. The basics of network reconstruction along with the limitations of gene
network inference, the enrichment and survival analysis, evolution, robustness-resilience and cascades
in complex networks, are described. Finally, an indicative and suggestive example of a cancer
gene co-expression network inference and analysis is given.
Collapse
Affiliation(s)
- A.C. Iliopoulos
- Research and Development Department, Research Genetic Cancer Centre S.A., Florina, Greece
| | - G. Beis
- Research and Development Department, Research Genetic Cancer Centre S.A., Florina, Greece
| | - P. Apostolou
- Research and Development Department, Research Genetic Cancer Centre S.A., Florina, Greece
| | - I. Papasotiriou
- Research Genetic Cancer Centre International GmbH, Zug, Switzerland
| |
Collapse
|
67
|
Nepomuceno-Chamorro IA, Nepomuceno JA, Galván-Rojas JL, Vega-Márquez B, Rubio-Escudero C. Using prior knowledge in the inference of gene association networks. APPL INTELL 2020. [DOI: 10.1007/s10489-020-01705-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
68
|
Ma B, Fang M, Jiao X. Inference of gene regulatory networks based on nonlinear ordinary differential equations. Bioinformatics 2020; 36:4885-4893. [DOI: 10.1093/bioinformatics/btaa032] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 12/30/2019] [Accepted: 01/15/2020] [Indexed: 01/05/2023] Open
Abstract
Abstract
Motivation
Gene regulatory networks (GRNs) capture the regulatory interactions between genes, resulting from the fundamental biological process of transcription and translation. In some cases, the topology of GRNs is not known, and has to be inferred from gene expression data. Most of the existing GRNs reconstruction algorithms are either applied to time-series data or steady-state data. Although time-series data include more information about the system dynamics, steady-state data imply stability of the underlying regulatory networks.
Results
In this article, we propose a method for inferring GRNs from time-series and steady-state data jointly. We make use of a non-linear ordinary differential equations framework to model dynamic gene regulation and an importance measurement strategy to infer all putative regulatory links efficiently. The proposed method is evaluated extensively on the artificial DREAM4 dataset and two real gene expression datasets of yeast and Escherichia coli. Based on public benchmark datasets, the proposed method outperforms other popular inference algorithms in terms of overall score. By comparing the performance on the datasets with different scales, the results show that our method still keeps good robustness and accuracy at a low computational complexity.
Availability and implementation
The proposed method is written in the Python language, and is available at: https://github.com/lab319/GRNs_nonlinear_ODEs
Supplementary information
Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Baoshan Ma
- College of Information Science and Technology, Dalian Maritime University, Dalian 116026, China
| | - Mingkun Fang
- College of Information Science and Technology, Dalian Maritime University, Dalian 116026, China
| | - Xiangtian Jiao
- College of Information Science and Technology, Dalian Maritime University, Dalian 116026, China
| |
Collapse
|
69
|
Likhoshvai VA, Golubyatnikov VP, Khlebodarova TM. Limit cycles in models of circular gene networks regulated by negative feedback loops. BMC Bioinformatics 2020; 21:255. [PMID: 32921311 PMCID: PMC7488683 DOI: 10.1186/s12859-020-03598-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 06/10/2020] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The regulatory feedback loops that present in structural and functional organization of molecular-genetic systems and the phenomenon of the regulatory signal delay, a time period between the moment of signal reception and its implementation, provide natural conditions for complicated dynamic regimes in these systems. The delay phenomenon at the intracellular level is a consequence of the matrix principle of data transmission, implemented through the rather complex processes of transcription and translation.However, the rules of the influence of system structure on system dynamics are not clearly understood. Knowledge of these rules is particularly important for construction of synthetic gene networks with predetermined properties. RESULTS We study dynamical properties of models of simplest circular gene networks regulated by negative feedback mechanisms. We have shown existence and stability of oscillating trajectories (cycles) in these models. Two algorithms of construction and localization of these cycles have been proposed. For one of these models, we have solved an inverse problem of parameters identification. CONCLUSIONS The modeling results demonstrate that non-stationary dynamics in the models of circular gene networks with negative feedback loops is achieved by a high degree of non-linearity of the mechanism of the autorepressor influence on its own expression, by the presence of regulatory signal delay, the value of which must exceed a certain critical value, and transcription/translation should be initiated from a sufficiently strong promoter/Shine-Dalgarno site. We believe that the identified patterns are key elements of the oscillating construction design.
Collapse
Affiliation(s)
- Vitaly A Likhoshvai
- Department of Systems Biology, Institute of Cytology and Genetics, Siberian Branch RAS, Novosibirsk, Russia
| | - Vladimir P Golubyatnikov
- Laboratory of Inverse Problems of Mathematical Physics, Sobolev Institute of Mathematics Siberian Branch RAS, Novosibirsk, Russia.
- Novosibirsk State University, Novosibirsk, Russia.
| | - Tamara M Khlebodarova
- Department of Systems Biology, Institute of Cytology and Genetics, Siberian Branch RAS, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| |
Collapse
|
70
|
Hayama Nishida CE, Costa Bianchi RA, Reali Costa AH. A framework to shift basins of attraction of gene regulatory networks through batch reinforcement learning. Artif Intell Med 2020; 107:101853. [PMID: 32828434 DOI: 10.1016/j.artmed.2020.101853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/23/2020] [Accepted: 03/31/2020] [Indexed: 11/25/2022]
Abstract
A major challenge in gene regulatory networks (GRN) of biological systems is to discover when and what interventions should be applied to shift them to healthy phenotypes. A set of gene activity profiles, called basin of attraction (BOA), takes this network to a specific phenotype; therefore, a healthy BOA leads the GRN to a healthy phenotype. However, without the complete observability of the genes, it is not possible to identify whether the current BOA is healthy. In this article we investigate external interventions in GRN with partial observability aiming to bring it to healthy BOAs. We propose a new batch reinforcement learning method (BRL), called mSFQI, to define intervention strategies based on the probabilities of the gene activity profiles being in healthy BOAs, which are calculated from a set of previous observed experiences. BRL uses approximation functions and repeated applications of previous experiences to accelerate learning. Results demonstrate that our proposal can quickly shift a partially observable GRN to healthy BOAs, while reducing the number of interventions. In addition, when observability is poor, mSFQI produces better results when the probabilities for a greater amount of previous observations are available.
Collapse
|
71
|
Sekula M, Gaskins J, Datta S. A sparse Bayesian factor model for the construction of gene co-expression networks from single-cell RNA sequencing count data. BMC Bioinformatics 2020; 21:361. [PMID: 32811424 PMCID: PMC7437941 DOI: 10.1186/s12859-020-03707-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 08/04/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Gene co-expression networks (GCNs) are powerful tools that enable biologists to examine associations between genes during different biological processes. With the advancement of new technologies, such as single-cell RNA sequencing (scRNA-seq), there is a need for developing novel network methods appropriate for new types of data. RESULTS We present a novel sparse Bayesian factor model to explore the network structure associated with genes in scRNA-seq data. Latent factors impact the gene expression values for each cell and provide flexibility to account for common features of scRNA-seq: high proportions of zero values, increased cell-to-cell variability, and overdispersion due to abnormally large expression counts. From our model, we construct a GCN by analyzing the positive and negative associations of the factors that are shared between each pair of genes. CONCLUSIONS Simulation studies demonstrate that our methodology has high power in identifying gene-gene associations while maintaining a nominal false discovery rate. In real data analyses, our model identifies more known and predicted protein-protein interactions than other competing network models.
Collapse
Affiliation(s)
- Michael Sekula
- Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, KY, USA.
| | - Jeremy Gaskins
- Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, KY, USA
| | - Susmita Datta
- Department of Biostatistics, University of Florida, Gainesville, FL, USA
| |
Collapse
|
72
|
Delgado-Chaves FM, Gómez-Vela F, Divina F, García-Torres M, Rodriguez-Baena DS. Computational Analysis of the Global Effects of Ly6E in the Immune Response to Coronavirus Infection Using Gene Networks. Genes (Basel) 2020; 11:E831. [PMID: 32708319 PMCID: PMC7397019 DOI: 10.3390/genes11070831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 06/26/2020] [Accepted: 07/13/2020] [Indexed: 12/21/2022] Open
Abstract
Gene networks have arisen as a promising tool in the comprehensive modeling and analysis of complex diseases. Particularly in viral infections, the understanding of the host-pathogen mechanisms, and the immune response to these, is considered a major goal for the rational design of appropriate therapies. For this reason, the use of gene networks may well encourage therapy-associated research in the context of the coronavirus pandemic, orchestrating experimental scrutiny and reducing costs. In this work, gene co-expression networks were reconstructed from RNA-Seq expression data with the aim of analyzing the time-resolved effects of gene Ly6E in the immune response against the coronavirus responsible for murine hepatitis (MHV). Through the integration of differential expression analyses and reconstructed networks exploration, significant differences in the immune response to virus were observed in Ly6E Δ H S C compared to wild type animals. Results show that Ly6E ablation at hematopoietic stem cells (HSCs) leads to a progressive impaired immune response in both liver and spleen. Specifically, depletion of the normal leukocyte mediated immunity and chemokine signaling is observed in the liver of Ly6E Δ H S C mice. On the other hand, the immune response in the spleen, which seemed to be mediated by an intense chromatin activity in the normal situation, is replaced by ECM remodeling in Ly6E Δ H S C mice. These findings, which require further experimental characterization, could be extrapolated to other coronaviruses and motivate the efforts towards novel antiviral approaches.
Collapse
|
73
|
Acerbi E, Hortova-Kohoutkova M, Choera T, Keller N, Fric J, Stella F, Romani L, Zelante T. Modeling Approaches Reveal New Regulatory Networks in Aspergillus fumigatus Metabolism. J Fungi (Basel) 2020; 6:jof6030108. [PMID: 32674323 PMCID: PMC7557846 DOI: 10.3390/jof6030108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/06/2020] [Accepted: 07/10/2020] [Indexed: 02/07/2023] Open
Abstract
Systems biology approaches are extensively used to model and reverse-engineer gene regulatory networks from experimental data. Indoleamine 2,3-dioxygenases (IDOs)-belonging in the heme dioxygenase family-degrade l-tryptophan to kynurenines. These enzymes are also responsible for the de novo synthesis of nicotinamide adenine dinucleotide (NAD+). As such, they are expressed by a variety of species, including fungi. Interestingly, Aspergillus may degrade l-tryptophan not only via IDO but also via alternative pathways. Deciphering the molecular interactions regulating tryptophan metabolism is particularly critical for novel drug target discovery designed to control pathogen determinants in invasive infections. Using continuous time Bayesian networks over a time-course gene expression dataset, we inferred the global regulatory network controlling l-tryptophan metabolism. The method unravels a possible novel approach to target fungal virulence factors during infection. Furthermore, this study represents the first application of continuous-time Bayesian networks as a gene network reconstruction method in Aspergillus metabolism. The experiment showed that the applied computational approach may improve the understanding of metabolic networks over traditional pathways.
Collapse
Affiliation(s)
- Enzo Acerbi
- Nlytics Pte. Ltd., Singapore 637551, Singapore;
| | - Marcela Hortova-Kohoutkova
- Centre for Translational Medicine, International Clinical Research Centre, St. Anne’s University Hospital Brno, 65691 Brno, Czech Republic; (M.H.-K.); (J.F.)
| | - Tsokyi Choera
- Department of Medical Microbiology and Immunology, Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA; (T.C.); (N.K.)
| | - Nancy Keller
- Department of Medical Microbiology and Immunology, Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA; (T.C.); (N.K.)
| | - Jan Fric
- Centre for Translational Medicine, International Clinical Research Centre, St. Anne’s University Hospital Brno, 65691 Brno, Czech Republic; (M.H.-K.); (J.F.)
- Institute of Hematology and Blood Transfusion, 12800 Prague, Czech Republic
| | - Fabio Stella
- Department of Informatics, Systems and Communication, University of Milano-Bicocca, Viale Sarca 336, Building U14, 20126 Milan, Italy;
| | - Luigina Romani
- Department of Experimental Medicine, University of Perugia, 06132 Perugia, Italy;
| | - Teresa Zelante
- Department of Experimental Medicine, University of Perugia, 06132 Perugia, Italy;
- Correspondence: ; Tel.: +39-075-585-8236
| |
Collapse
|
74
|
Vinga S. Structured sparsity regularization for analyzing high-dimensional omics data. Brief Bioinform 2020; 22:77-87. [PMID: 32597465 DOI: 10.1093/bib/bbaa122] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/18/2022] Open
Abstract
The development of new molecular and cell technologies is having a significant impact on the quantity of data generated nowadays. The growth of omics databases is creating a considerable potential for knowledge discovery and, concomitantly, is bringing new challenges to statistical learning and computational biology for health applications. Indeed, the high dimensionality of these data may hamper the use of traditional regression methods and parameter estimation algorithms due to the intrinsic non-identifiability of the inherent optimization problem. Regularized optimization has been rising as a promising and useful strategy to solve these ill-posed problems by imposing additional constraints in the solution parameter space. In particular, the field of statistical learning with sparsity has been significantly contributing to building accurate models that also bring interpretability to biological observations and phenomena. Beyond the now-classic elastic net, one of the best-known methods that combine lasso with ridge penalizations, we briefly overview recent literature on structured regularizers and penalty functions that have been applied in biomedical data to build parsimonious models in a variety of underlying contexts, from survival to generalized linear models. These methods include functions of $\ell _k$-norms and network-based penalties that take into account the inherent relationships between the features. The successful application to omics data illustrates the potential of sparse structured regularization for identifying disease's molecular signatures and for creating high-performance clinical decision support systems towards more personalized healthcare. Supplementary information: Supplementary data are available at Briefings in Bioinformatics online.
Collapse
Affiliation(s)
- Susana Vinga
- INESC-ID, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
| |
Collapse
|
75
|
Argelaguet R, Arnol D, Bredikhin D, Deloro Y, Velten B, Marioni JC, Stegle O. MOFA+: a statistical framework for comprehensive integration of multi-modal single-cell data. Genome Biol 2020; 21:111. [PMID: 32393329 PMCID: PMC7212577 DOI: 10.1186/s13059-020-02015-1] [Citation(s) in RCA: 263] [Impact Index Per Article: 65.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Accepted: 04/13/2020] [Indexed: 12/17/2022] Open
Abstract
Technological advances have enabled the profiling of multiple molecular layers at single-cell resolution, assaying cells from multiple samples or conditions. Consequently, there is a growing need for computational strategies to analyze data from complex experimental designs that include multiple data modalities and multiple groups of samples. We present Multi-Omics Factor Analysis v2 (MOFA+), a statistical framework for the comprehensive and scalable integration of single-cell multi-modal data. MOFA+ reconstructs a low-dimensional representation of the data using computationally efficient variational inference and supports flexible sparsity constraints, allowing to jointly model variation across multiple sample groups and data modalities.
Collapse
Affiliation(s)
- Ricard Argelaguet
- European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridgeshire, CB10 1SD, UK.
| | - Damien Arnol
- European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Danila Bredikhin
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Yonatan Deloro
- European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Britta Velten
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Division of Computational Genomics and Systems Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - John C Marioni
- European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridgeshire, CB10 1SD, UK.
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, CB2 0RE, UK.
- Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK.
| | - Oliver Stegle
- European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridgeshire, CB10 1SD, UK.
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.
- Division of Computational Genomics and Systems Genetics, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| |
Collapse
|
76
|
Cirrone J, Brooks MD, Bonneau R, Coruzzi GM, Shasha DE. OutPredict: multiple datasets can improve prediction of expression and inference of causality. Sci Rep 2020; 10:6804. [PMID: 32321967 PMCID: PMC7176633 DOI: 10.1038/s41598-020-63347-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 03/26/2020] [Indexed: 01/09/2023] Open
Abstract
The ability to accurately predict the causal relationships from transcription factors to genes would greatly enhance our understanding of transcriptional dynamics. This could lead to applications in which one or more transcription factors could be manipulated to effect a change in genes leading to the enhancement of some desired trait. Here we present a method called OutPredict that constructs a model for each gene based on time series (and other) data and that predicts gene's expression in a previously unseen subsequent time point. The model also infers causal relationships based on the most important transcription factors for each gene model, some of which have been validated from previous physical experiments. The method benefits from known network edges and steady-state data to enhance predictive accuracy. Our results across B. subtilis, Arabidopsis, E.coli, Drosophila and the DREAM4 simulated in silico dataset show improved predictive accuracy ranging from 40% to 60% over other state-of-the-art methods. We find that gene expression models can benefit from the addition of steady-state data to predict expression values of time series. Finally, we validate, based on limited available data, that the influential edges we infer correspond to known relationships significantly more than expected by chance or by state-of-the-art methods.
Collapse
Affiliation(s)
- Jacopo Cirrone
- Courant Institute of Mathematical Sciences, Department of Computer Science, New York University, New York, NY, 10012, USA.
| | - Matthew D Brooks
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, 10003, USA
| | - Richard Bonneau
- Courant Institute of Mathematical Sciences, Department of Computer Science, New York University, New York, NY, 10012, USA
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, 10003, USA
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, NY, 10010, USA
| | - Gloria M Coruzzi
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, 10003, USA
| | - Dennis E Shasha
- Courant Institute of Mathematical Sciences, Department of Computer Science, New York University, New York, NY, 10012, USA
| |
Collapse
|
77
|
Law J, Ng K, Windram OPF. The Phenotype Paradox: Lessons From Natural Transcriptome Evolution on How to Engineer Plants. FRONTIERS IN PLANT SCIENCE 2020; 11:75. [PMID: 32133018 PMCID: PMC7040092 DOI: 10.3389/fpls.2020.00075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 01/20/2020] [Indexed: 06/10/2023]
Abstract
Plants have evolved genome complexity through iterative rounds of single gene and whole genome duplication. This has led to substantial expansion in transcription factor numbers following preferential retention and subsequent functional divergence of these regulatory genes. Here we review how this simple evolutionary network rewiring process, regulatory gene duplication followed by functional divergence, can be used to inspire synthetic biology approaches that seek to develop novel phenotypic variation for future trait based breeding programs in plants.
Collapse
Affiliation(s)
- Justin Law
- Grand Challenges in Ecosystems and the Environment, Imperial College London, Ascot, United Kingdom
| | - Kangbo Ng
- The Francis Crick Institute, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Oliver P. F. Windram
- Grand Challenges in Ecosystems and the Environment, Imperial College London, Ascot, United Kingdom
| |
Collapse
|
78
|
Wang H, Lian Y, Li C, Ma Y, Yan Z, Dong C. SIN-KNO: A method of gene regulatory network inference using single-cell transcription and gene knockout data. J Bioinform Comput Biol 2020; 17:1950035. [PMID: 32019417 DOI: 10.1142/s0219720019500355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
As a tool of interpreting and analyzing genetic data, gene regulatory network (GRN) could reveal regulatory relationships between genes, proteins, and small molecules, as well as understand physiological activities and functions within biological cells, interact in pathways, and how to make changes in the organism. Traditional GRN research focuses on the analysis of the regulatory relationships through the average of cellular gene expressions. These methods are difficult to identify the cell heterogeneity of gene expression. Existing methods for inferring GRN using single-cell transcriptional data lack expression information when genes reach steady state, and the high dimensionality of single-cell data leads to high temporal and spatial complexity of the algorithm. In order to solve the problem in traditional GRN inference methods, including the lack of cellular heterogeneity information, single-cell data complexity and lack of steady-state information, we propose a method for GRN inference using single-cell transcription and gene knockout data, called SINgle-cell transcription data-KNOckout data (SIN-KNO), which focuses on combining dynamic and steady-state information of regulatory relationship contained in gene expression. Capturing cell heterogeneity information could help understand the gene expression difference in different cells. So, we could observe gene expression changes more accurately. Gene knockout data could observe the gene expression levels at steady-state of all other genes when one gene is knockout. Classifying the genes before analyzing the single-cell data could determine a large number of non-existent regulation, greatly reducing the number of regulation required for inference. In order to show the efficiency, the proposed method has been compared with several typical methods in this area including GENIE3, JUMP3, and SINCERITIES. The results of the evaluation indicate that the proposed method can analyze the diversified information contained in the two types of data, establish a more accurate gene regulation network, and improve the computational efficiency. The method provides a new thinking for dealing with large datasets and high computational complexity of single-cell data in the GRN inference.
Collapse
Affiliation(s)
- Huiqing Wang
- College of Information and Computer, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Yuanyuan Lian
- College of Information and Computer, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Chun Li
- College of Information and Computer, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Yue Ma
- College of Information and Computer, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Zhiliang Yan
- College of Information and Computer, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Chunlin Dong
- Dryland Agriculture Research Center, Shanxi Academy of Agricultural Sciences, Taiyuan, Shanxi, China
| |
Collapse
|
79
|
Li W, Zhang W, Zhang J. A Novel Model Integration Network Inference Algorithm with Clustering and Hub Genes Finding. Mol Inform 2020; 39:e1900075. [DOI: 10.1002/minf.201900075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 01/14/2020] [Indexed: 11/08/2022]
Affiliation(s)
- Wenchao Li
- State Key Laboratory of Industrial Control TechnologyInstitute of Cyber-Systems and Control of Zhejiang University Hangzhou China
| | - Wei Zhang
- State Key Laboratory of Industrial Control TechnologyInstitute of Cyber-Systems and Control of Zhejiang University Hangzhou China
| | - Jianming Zhang
- State Key Laboratory of Industrial Control TechnologyInstitute of Cyber-Systems and Control of Zhejiang University Hangzhou China
| |
Collapse
|
80
|
Manzoni C, Lewis PA, Ferrari R. Network Analysis for Complex Neurodegenerative Diseases. CURRENT GENETIC MEDICINE REPORTS 2020. [DOI: 10.1007/s40142-020-00181-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Abstract
Purpose of Review
Biomedicine is witnessing a paradigm shift in the way complex disorders are investigated. In particular, the need for big data interpretation has led to the development of pipelines that require the cooperation of different fields of expertise, including medicine, functional biology, informatics, mathematics and systems biology. This review sits at the crossroad of different disciplines and surveys the recent developments in the use of graph theory (in the form of network analysis) to interpret large and different datasets in the context of complex neurodegenerative diseases. It aims at a professional audience with different backgrounds.
Recent Findings
Biomedicine has entered the era of big data, and this is actively changing the way we approach and perform research. The increase in size and power of biomedical studies has led to the establishment of multi-centre, international working groups coordinating open access platforms for data generation, storage and analysis. Particularly, pipelines for data interpretation are under development, and network analysis is gaining momentum since it represents a versatile approach to study complex systems made of interconnected multiple players.
Summary
We will describe the era of big data in biomedicine and survey the major freely accessible multi-omics datasets. We will then introduce the principles of graph theory and provide examples of network analysis applied to the interpretation of complex neurodegenerative disorders.
Collapse
|
81
|
Mercatelli D, Scalambra L, Triboli L, Ray F, Giorgi FM. Gene regulatory network inference resources: A practical overview. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1863:194430. [PMID: 31678629 DOI: 10.1016/j.bbagrm.2019.194430] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 09/06/2019] [Accepted: 09/09/2019] [Indexed: 02/08/2023]
Abstract
Transcriptional regulation is a fundamental molecular mechanism involved in almost every aspect of life, from homeostasis to development, from metabolism to behavior, from reaction to stimuli to disease progression. In recent years, the concept of Gene Regulatory Networks (GRNs) has grown popular as an effective applied biology approach for describing the complex and highly dynamic set of transcriptional interactions, due to its easy-to-interpret features. Since cataloguing, predicting and understanding every GRN connection in all species and cellular contexts remains a great challenge for biology, researchers have developed numerous tools and methods to infer regulatory processes. In this review, we catalogue these methods in six major areas, based on the dominant underlying information leveraged to infer GRNs: Coexpression, Sequence Motifs, Chromatin Immunoprecipitation (ChIP), Orthology, Literature and Protein-Protein Interaction (PPI) specifically focused on transcriptional complexes. The methods described here cover a wide range of user-friendliness: from web tools that require no prior computational expertise to command line programs and algorithms for large scale GRN inferences. Each method for GRN inference described herein effectively illustrates a type of transcriptional relationship, with many methods being complementary to others. While a truly holistic approach for inferring and displaying GRNs remains one of the greatest challenges in the field of systems biology, we believe that the integration of multiple methods described herein provides an effective means with which experimental and computational biologists alike may obtain the most complete pictures of transcriptional relationships. This article is part of a Special Issue entitled: Transcriptional Profiles and Regulatory Gene Networks edited by Dr. Federico Manuel Giorgi and Dr. Shaun Mahony.
Collapse
Affiliation(s)
- Daniele Mercatelli
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Laura Scalambra
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Luca Triboli
- Centre for Integrative Biology (CIBIO), University of Trento, Italy
| | - Forest Ray
- Department of Systems Biology, Columbia University Medical Center, New York, NY, United States
| | - Federico M Giorgi
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.
| |
Collapse
|
82
|
Chew G, Petretto E. Transcriptional Networks of Microglia in Alzheimer's Disease and Insights into Pathogenesis. Genes (Basel) 2019; 10:E798. [PMID: 31614849 PMCID: PMC6826883 DOI: 10.3390/genes10100798] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/30/2019] [Accepted: 10/11/2019] [Indexed: 02/07/2023] Open
Abstract
Microglia, the main immune cells of the central nervous system, are increasingly implicated in Alzheimer's disease (AD). Manifold transcriptomic studies in the brain have not only highlighted microglia's role in AD pathogenesis, but also mapped crucial pathological processes and identified new therapeutic targets. An important component of many of these transcriptomic studies is the investigation of gene expression networks in AD brain, which has provided important new insights into how coordinated gene regulatory programs in microglia (and other cell types) underlie AD pathogenesis. Given the rapid technological advancements in transcriptional profiling, spanning from microarrays to single-cell RNA sequencing (scRNA-seq), tools used for mapping gene expression networks have evolved to keep pace with the unique features of each transcriptomic platform. In this article, we review the trajectory of transcriptomic network analyses in AD from brain to microglia, highlighting the corresponding methodological developments. Lastly, we discuss examples of how transcriptional network analysis provides new insights into AD mechanisms and pathogenesis.
Collapse
Affiliation(s)
- Gabriel Chew
- Programme in Cardiovascular and Metabolic Disorders, Duke-NUS Medical School, 8 College Road, 69857 Singapore, Singapore.
| | - Enrico Petretto
- Programme in Cardiovascular and Metabolic Disorders, Duke-NUS Medical School, 8 College Road, 69857 Singapore, Singapore.
| |
Collapse
|