1
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Wu Y, Li Y, Zhou Y, Bai X, Liu Y. Bioinformatics and systems-biology approach to identify common pathogenic mechanisms for COVID-19 and systemic lupus erythematosus. Autoimmunity 2024; 57:2304826. [PMID: 38332666 DOI: 10.1080/08916934.2024.2304826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 01/07/2024] [Indexed: 02/10/2024]
Abstract
BACKGROUND The Coronavirus disease 2019 (COVID-19) pandemic has brought a heavy burden to the world, interestingly, it shares many clinical symptoms with systemic lupus erythematosus (SLE). It is unclear whether there is a similar pathological process between COVID-9 and SLE. In addition, we don't know how to treat SLE patients with COVID-19. In this study, we analyse the potential similar pathogenesis between SLE and COVID-19 and explore their possible drug regimens using bioinformatics and systems biology approaches. METHODS The common differentially expressed genes (DEGs) were extracted from the COVID-19 datasets and the SLE datasets for functional enrichment, pathway analysis and candidate drug analysis. RESULT Based on the two transcriptome datasets between COVID-19 and SLE, 325 common DEGs were selected. Hub genes were identified by protein-protein interaction (PPI) analysis. few found a variety of similar functional changes between COVID-19 and SLE, which may be related to the pathogenesis of COVID-19. Besides, we explored the related regulatory networks. Then, through drug target matching, we found many candidate drugs for patients with COVID-19 only or COVID-19 combined with SLE. CONCLUSION COVID-19 and SLE patients share many common hub genes, related pathways and regulatory networks. Based on these common targets, we found many potential drugs that could be used in treating patient with COVID-19 or COVID-19 combined with SLE.
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Affiliation(s)
- Yinlan Wu
- Department of Rheumatology and Immunology, West China Hospital, Sichuan University, Chengdu, China
- Rare Diseases Center, West China Hospital, Sichuan University, Chengdu, China
- Institute of Immunology and Inflammation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Yanhong Li
- Department of Rheumatology and Immunology, West China Hospital, Sichuan University, Chengdu, China
- Rare Diseases Center, West China Hospital, Sichuan University, Chengdu, China
- Institute of Immunology and Inflammation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Yu Zhou
- Department of Respiratory and Critical Care Medicine, Chengdu First People's Hospital, Chengdu, China
| | - Xiufeng Bai
- Institute of Immunology and Inflammation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
- Laboratory of Human Disease and Immunotherapies, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Liu
- Department of Rheumatology and Immunology, West China Hospital, Sichuan University, Chengdu, China
- Rare Diseases Center, West China Hospital, Sichuan University, Chengdu, China
- Institute of Immunology and Inflammation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
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2
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Kuang N, Ma Q, Zheng X, Meng X, Zhai Z, Li Q, Pan J. GeTeSEPdb: A comprehensive database and online tool for the identification and analysis of gene profiles with temporal-specific expression patterns. Comput Struct Biotechnol J 2024; 23:2488-2496. [PMID: 38939556 PMCID: PMC11208770 DOI: 10.1016/j.csbj.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 05/29/2024] [Accepted: 06/04/2024] [Indexed: 06/29/2024] Open
Abstract
Gene expression is dynamic and varies at different stages of processes. The identification of gene profiles with temporal-specific expression patterns can provide valuable insights into ongoing biological processes, such as the cell cycle, cell development, circadian rhythms, or responses to external stimuli such as drug treatments or viral infections. However, currently, no database defines, identifies or archives gene profiles with temporal-specific expression patterns. Here, using a high-throughput regression analysis approach, eight linear and nonlinear parametric models were fitted to gene expression profiles from time-series experiments to identify eight types of gene profiles with temporal-specific expression patterns. We curated 2684 time-series transcriptome datasets and identified 2644,370 gene profiles exhibiting temporal-specific expression patterns. The results were stored in the database GeTeSEPdb (gene profiles with temporal-specific expression patterns database, http://www.inbirg.com/GeTeSEPdb/). Moreover, we implemented an online tool to identify gene profiles with temporal-specific expression patterns from user-submitted data. In summary, GeTeSEPdb is a comprehensive web service that can be used to identify and analyse gene profiles with temporal-specific expression patterns. This approach facilitates the exploration of transcriptional changes and temporal patterns of responses. We firmly believe that GeTeSEPdb will become a valuable resource for biologists and bioinformaticians.
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Affiliation(s)
- Ni Kuang
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Qinfeng Ma
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Xiao Zheng
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Xuehang Meng
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Zhaoyu Zhai
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Qiang Li
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
| | - Jianbo Pan
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, China
- Precision Medicine Center, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China
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3
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Su AJ, Yendluri SC, Ünal E. Control of meiotic entry by dual inhibition of a key mitotic transcription factor. eLife 2024; 12:RP90425. [PMID: 38411169 PMCID: PMC10939502 DOI: 10.7554/elife.90425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024] Open
Abstract
The mitosis to meiosis transition requires dynamic changes in gene expression, but whether and how the mitotic transcriptional machinery is regulated during this transition is unknown. In budding yeast, SBF and MBF transcription factors initiate the mitotic gene expression program. Here, we report two mechanisms that work together to restrict SBF activity during meiotic entry: repression of the SBF-specific Swi4 subunit through LUTI-based regulation and inhibition of SBF by Whi5, a functional homolog of the Rb tumor suppressor. We find that untimely SBF activation causes downregulation of early meiotic genes and delays meiotic entry. These defects are largely driven by the SBF-target G1 cyclins, which block the interaction between the central meiotic regulator Ime1 and its cofactor Ume6. Our study provides insight into the role of SWI4LUTI in establishing the meiotic transcriptional program and demonstrates how the LUTI-based regulation is integrated into a larger regulatory network to ensure timely SBF activity.
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Affiliation(s)
- Amanda J Su
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Siri C Yendluri
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Elçin Ünal
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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4
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Ramos-Alonso L, Chymkowitch P. Maintaining transcriptional homeostasis during cell cycle. Transcription 2024; 15:1-21. [PMID: 37655806 PMCID: PMC11093055 DOI: 10.1080/21541264.2023.2246868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/31/2023] [Accepted: 08/03/2023] [Indexed: 09/02/2023] Open
Abstract
The preservation of gene expression patterns that define cellular identity throughout the cell division cycle is essential to perpetuate cellular lineages. However, the progression of cells through different phases of the cell cycle severely disrupts chromatin accessibility, epigenetic marks, and the recruitment of transcriptional regulators. Notably, chromatin is transiently disassembled during S-phase and undergoes drastic condensation during mitosis, which is a significant challenge to the preservation of gene expression patterns between cell generations. This article delves into the specific gene expression and chromatin regulatory mechanisms that facilitate the preservation of transcriptional identity during replication and mitosis. Furthermore, we emphasize our recent findings revealing the unconventional role of yeast centromeres and mitotic chromosomes in maintaining transcriptional fidelity beyond mitosis.
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Affiliation(s)
- Lucía Ramos-Alonso
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
| | - Pierre Chymkowitch
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
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5
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Fox J, Cummins B, Moseley RC, Gameiro M, Haase SB. A yeast cell cycle pulse generator model shows consistency with multiple oscillatory and checkpoint mutant datasets. Math Biosci 2024; 367:109102. [PMID: 37939998 PMCID: PMC10842220 DOI: 10.1016/j.mbs.2023.109102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 09/13/2023] [Accepted: 10/27/2023] [Indexed: 11/10/2023]
Abstract
Modeling biological systems holds great promise for speeding up the rate of discovery in systems biology by predicting experimental outcomes and suggesting targeted interventions. However, this process is dogged by an identifiability issue, in which network models and their parameters are not sufficiently constrained by coarse and noisy data to ensure unique solutions. In this work, we evaluated the capability of a simplified yeast cell-cycle network model to reproduce multiple observed transcriptomic behaviors under genomic mutations. We matched time-series data from both cycling and checkpoint arrested cells to model predictions using an asynchronous multi-level Boolean approach. We showed that this single network model, despite its simplicity, is capable of exhibiting dynamical behavior similar to the datasets in most cases, and we demonstrated the drop in severity of the identifiability issue that results from matching multiple datasets.
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Affiliation(s)
- Julian Fox
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA
| | - Breschine Cummins
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA.
| | | | - Marcio Gameiro
- Department of Mathematics, Rutgers University, New Brunswick, NJ, USA
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6
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Mineta K, Hirota J, Yamada K, Itoh T, Chen P, Iwakawa H, Takatsuka H, Nomoto Y, Ito M. MYB3R-mediated and cell cycle-dependent transcriptional regulation of a tobacco ortholog of SCARECROW-LIKE28 in synchronized cultures of BY-2 cells. PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2023; 40:353-359. [PMID: 38434109 PMCID: PMC10905365 DOI: 10.5511/plantbiotechnology.23.0515a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/15/2023] [Indexed: 03/05/2024]
Abstract
Although it is well known that hierarchical transcriptional networks are essential for various aspects of plant development and environmental response, little has been investigated about whether and how they also regulate the plant cell cycle. Recent studies on cell cycle regulation in Arabidopsis thaliana identified SCARECROW-LIKE28 (SCL28), a GRAS-type transcription factor, that constitutes a hierarchical transcriptional pathway comprised of MYB3R, SCL28 and SIAMESE-RELATED (SMR). In this pathway, MYB3R family proteins regulate the G2/M-specific transcription of the SCL28 gene, of which products, in turn, positively regulate the transcription of SMR genes encoding a group of plant-specific inhibitor proteins of cyclin-dependent kinases. However, this pathway with a role in cell cycle inhibition is solely demonstrated in A. thaliana, thus leaving open the question of whether and to what extent this pathway is evolutionarily conserved in plants. In this study, we conducted differential display RT-PCR on synchronized Nicotiana tabacum (tobacco) BY-2 cells and identified several M-phase-specific cDNA clones, one of which turned out to be a tobacco ortholog of SCL28 and was designated NtSCL28. We showed that NtSCL28 is expressed specifically during G2/M and early G1 in the synchronized cultures of BY-2 cells. NtSCL28 contains MYB3R-binding promoter elements, so-called mitosis-specific activator elements, and is upregulated by a hyperactive form of NtmybA2, one of the MYB3R proteins from tobacco. Our study indicated that a part of the hierarchical pathway identified in A. thaliana is equally operating in tobacco cells, suggesting the conservation of this pathway across different families in evolution of angiosperm.
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Affiliation(s)
- Keito Mineta
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Junya Hirota
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Kesuke Yamada
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Takashi Itoh
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Tokyo 113-0033, Japan
| | - Poyu Chen
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Hidekazu Iwakawa
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Hirotomo Takatsuka
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Yuji Nomoto
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Masaki Ito
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
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7
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Otálora-Otálora BA, López-Rivera JJ, Aristizábal-Guzmán C, Isaza-Ruget MA, Álvarez-Moreno CA. Host Transcriptional Regulatory Genes and Microbiome Networks Crosstalk through Immune Receptors Establishing Normal and Tumor Multiomics Metafirm of the Oral-Gut-Lung Axis. Int J Mol Sci 2023; 24:16638. [PMID: 38068961 PMCID: PMC10706695 DOI: 10.3390/ijms242316638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 11/13/2023] [Accepted: 11/18/2023] [Indexed: 12/18/2023] Open
Abstract
The microbiome has shown a correlation with the diet and lifestyle of each population in health and disease, the ability to communicate at the cellular level with the host through innate and adaptative immune receptors, and therefore an important role in modulating inflammatory process related to the establishment and progression of cancer. The oral cavity is one of the most important interaction windows between the human body and the environment, allowing the entry of an important number of microorganisms and their passage across the gastrointestinal tract and lungs. In this review, the contribution of the microbiome network to the establishment of systemic diseases like cancer is analyzed through their synergistic interactions and bidirectional crosstalk in the oral-gut-lung axis as well as its communication with the host cells. Moreover, the impact of the characteristic microbiota of each population in the formation of the multiomics molecular metafirm of the oral-gut-lung axis is also analyzed through state-of-the-art sequencing techniques, which allow a global study of the molecular processes involved of the flow of the microbiota environmental signals through cancer-related cells and its relationship with the establishment of the transcription factor network responsible for the control of regulatory processes involved with tumorigenesis.
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Affiliation(s)
| | - Juan Javier López-Rivera
- Grupo de Investigación INPAC, Specialized Laboratory, Clinica Universitaria Colombia, Clínica Colsanitas S.A., Bogotá 111321, Colombia;
| | - Claudia Aristizábal-Guzmán
- Grupo de Investigación INPAC, Unidad de Investigación, Fundación Universitaria Sanitas, Bogotá 110131, Colombia;
| | - Mario Arturo Isaza-Ruget
- Keralty, Sanitas International Organization, Grupo de Investigación INPAC, Fundación Universitaria Sanitas, Bogotá 110131, Colombia;
| | - Carlos Arturo Álvarez-Moreno
- Infectious Diseases Department, Clinica Universitaria Colombia, Clínica Colsanitas S.A., Bogotá 111321, Colombia;
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8
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Huang ZJ, Patel B, Lu WH, Yang TY, Tung WC, Bučinskas V, Greitans M, Wu YW, Lin PT. Yeast cell detection using fuzzy automatic contrast enhancement (FACE) and you only look once (YOLO). Sci Rep 2023; 13:16222. [PMID: 37758830 PMCID: PMC10533879 DOI: 10.1038/s41598-023-43452-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 09/24/2023] [Indexed: 09/29/2023] Open
Abstract
In contemporary biomedical research, the accurate automatic detection of cells within intricate microscopic imagery stands as a cornerstone for scientific advancement. Leveraging state-of-the-art deep learning techniques, this study introduces a novel amalgamation of Fuzzy Automatic Contrast Enhancement (FACE) and the You Only Look Once (YOLO) framework to address this critical challenge of automatic cell detection. Yeast cells, representing a vital component of the fungi family, hold profound significance in elucidating the intricacies of eukaryotic cells and human biology. The proposed methodology introduces a paradigm shift in cell detection by optimizing image contrast through optimal fuzzy clustering within the FACE approach. This advancement mitigates the shortcomings of conventional contrast enhancement techniques, minimizing artifacts and suboptimal outcomes. Further enhancing contrast, a universal contrast enhancement variable is ingeniously introduced, enriching image clarity with automatic precision. Experimental validation encompasses a diverse range of yeast cell images subjected to rigorous quantitative assessment via Root-Mean-Square Contrast and Root-Mean-Square Deviation (RMSD). Comparative analyses against conventional enhancement methods showcase the superior performance of the FACE-enhanced images. Notably, the integration of the innovative You Only Look Once (YOLOv5) facilitates automatic cell detection within a finely partitioned grid system. This leads to the development of two models-one operating on pristine raw images, the other harnessing the enriched landscape of FACE-enhanced imagery. Strikingly, the FACE enhancement achieves exceptional accuracy in automatic yeast cell detection by YOLOv5 across both raw and enhanced images. Comprehensive performance evaluations encompassing tenfold accuracy assessments and confidence scoring substantiate the robustness of the FACE-YOLO model. Notably, the integration of FACE-enhanced images serves as a catalyst, significantly elevating the performance of YOLOv5 detection. Complementing these efforts, OpenCV lends computational acumen to delineate precise yeast cell contours and coordinates, augmenting the precision of cell detection.
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Affiliation(s)
- Zheng-Jie Huang
- Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan
| | - Brijesh Patel
- Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan
| | - Wei-Hao Lu
- Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan
| | - Tz-Yu Yang
- Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan
| | - Wei-Cheng Tung
- Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan
| | | | - Modris Greitans
- Institute of Electronics and Computer Science, Riga, 1006, Latvia
| | - Yu-Wei Wu
- Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, 11031, Taiwan.
- Clinical Big Data Research Center, Taipei Medical University Hospital, Taipei, 11031, Taiwan.
- TMU Research Center for Digestive Medicine, Taipei Medical University, Taipei, 11031, Taiwan.
| | - Po Ting Lin
- Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan.
- Intelligent Manufacturing Innovation Center, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan.
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9
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Sosa Ponce ML, Remedios MH, Moradi-Fard S, Cobb JA, Zaremberg V. SIR telomere silencing depends on nuclear envelope lipids and modulates sensitivity to a lysolipid. J Cell Biol 2023; 222:e202206061. [PMID: 37042812 PMCID: PMC10103788 DOI: 10.1083/jcb.202206061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 11/29/2022] [Accepted: 03/24/2023] [Indexed: 04/13/2023] Open
Abstract
The nuclear envelope (NE) is important in maintaining genome organization. The role of lipids in communication between the NE and telomere regulation was investigated, including how changes in lipid composition impact gene expression and overall nuclear architecture. Yeast was treated with the non-metabolizable lysophosphatidylcholine analog edelfosine, known to accumulate at the perinuclear ER. Edelfosine induced NE deformation and disrupted telomere clustering but not anchoring. Additionally, the association of Sir4 at telomeres decreased. RNA-seq analysis showed altered expression of Sir-dependent genes located at sub-telomeric (0-10 kb) regions, consistent with Sir4 dispersion. Transcriptomic analysis revealed that two lipid metabolic circuits were activated in response to edelfosine, one mediated by the membrane sensing transcription factors, Spt23/Mga2, and the other by a transcriptional repressor, Opi1. Activation of these transcriptional programs resulted in higher levels of unsaturated fatty acids and the formation of nuclear lipid droplets. Interestingly, cells lacking Sir proteins displayed resistance to unsaturated-fatty acids and edelfosine, and this phenotype was connected to Rap1.
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Affiliation(s)
| | | | - Sarah Moradi-Fard
- Departments of Biochemistry and Molecular Biology and Oncology, Cumming School of Medicine, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Calgary, Canada
| | - Jennifer A. Cobb
- Departments of Biochemistry and Molecular Biology and Oncology, Cumming School of Medicine, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Calgary, Canada
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, Canada
| | - Vanina Zaremberg
- Department of Biological Sciences, University of Calgary, Calgary, Canada
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10
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Cummins B, Motta FC, Moseley RC, Deckard A, Campione S, Gameiro M, Gedeon T, Mischaikow K, Haase SB. Experimental guidance for discovering genetic networks through hypothesis reduction on time series. PLoS Comput Biol 2022; 18:e1010145. [PMID: 36215333 PMCID: PMC9584434 DOI: 10.1371/journal.pcbi.1010145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 10/20/2022] [Accepted: 09/05/2022] [Indexed: 11/19/2022] Open
Abstract
Large programs of dynamic gene expression, like cell cyles and circadian rhythms, are controlled by a relatively small "core" network of transcription factors and post-translational modifiers, working in concerted mutual regulation. Recent work suggests that system-independent, quantitative features of the dynamics of gene expression can be used to identify core regulators. We introduce an approach of iterative network hypothesis reduction from time-series data in which increasingly complex features of the dynamic expression of individual, pairs, and entire collections of genes are used to infer functional network models that can produce the observed transcriptional program. The culmination of our work is a computational pipeline, Iterative Network Hypothesis Reduction from Temporal Dynamics (Inherent dynamics pipeline), that provides a priority listing of targets for genetic perturbation to experimentally infer network structure. We demonstrate the capability of this integrated computational pipeline on synthetic and yeast cell-cycle data.
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Affiliation(s)
- Breschine Cummins
- Department of Mathematical Sciences, Montana State University, Bozeman, Montana, United States of America
| | - Francis C. Motta
- Department of Mathematical Sciences, Florida Atlantic University, Boca Raton, Florida, United States of America
| | - Robert C. Moseley
- Department of Biology, Duke University, Durham, North Carolina, United States of America
| | - Anastasia Deckard
- Geometric Data Analytics, Durham, North Carolina, United States of America
| | - Sophia Campione
- Department of Biology, Duke University, Durham, North Carolina, United States of America
| | - Marcio Gameiro
- Department of Mathematics, Rutgers University, New Brunswick, New Jersey, United States of America
- Instituto de Ciências Matemáticas e de Computação, Universidade de São Paulo, São Carlos, São Paulo, Brazil
| | - Tomáš Gedeon
- Department of Mathematical Sciences, Montana State University, Bozeman, Montana, United States of America
| | - Konstantin Mischaikow
- Department of Mathematics, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Steven B. Haase
- Department of Biology, Duke University, Durham, North Carolina, United States of America
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11
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Gamage HN, Chetty M, Shatte A, Hallinan J. Filter feature selection based Boolean Modelling for Genetic Network Inference. Biosystems 2022; 221:104757. [PMID: 36007675 DOI: 10.1016/j.biosystems.2022.104757] [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: 02/24/2022] [Revised: 08/04/2022] [Accepted: 08/04/2022] [Indexed: 11/02/2022]
Abstract
The reconstruction of Gene Regulatory Networks (GRNs) from time series gene expression data is highly relevant for the discovery of complex biological interactions and dynamics. Various computational strategies have been developed for this task, but most approaches have low computational efficiency and are not able to cope with high-dimensional, low sample-number, gene expression data. In this paper, we introduce a novel combined filter feature selection approach for efficient and accurate inference of GRNs. A Boolean framework for network modelling is used to demonstrate the efficacy of the proposed approach. Using discretized microarray expression data, the genes most relevant to each target gene are first filtered using ReliefF, an instance-based feature ranking method that is here applied for the first time to GRN inference. Then, further gene selection from the filtered-gene list is done using a mutual information-based min-redundancy max-relevance criterion by eliminating irrelevant genes. This combined method is executed on resampled datasets to finalize the optimal set of regulatory genes. Building upon our previous research, a Pearson correlation coefficient-based Boolean modelling approach is utilized for the efficient identification of the optimal regulatory rules associated with selected regulatory genes. The proposed approach was evaluated using gene expression datasets from small-scale and medium-scale real gene networks, and was observed to be more effective than Linear Discriminant Analysis, performed better than the individual feature selection methods, and obtained improved Structural Accuracy with a higher number of true positives than other state-of-the-art methods, while outperforming these methods with respect to Dynamic Accuracy and efficiency.
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Affiliation(s)
| | - Madhu Chetty
- Health Innovation and Transformation Centre, Federation University, Victoria, Australia
| | - Adrian Shatte
- Health Innovation and Transformation Centre, Federation University, Victoria, Australia
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12
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Pušnik Ž, Mraz M, Zimic N, Moškon M. Review and assessment of Boolean approaches for inference of gene regulatory networks. Heliyon 2022; 8:e10222. [PMID: 36033302 PMCID: PMC9403406 DOI: 10.1016/j.heliyon.2022.e10222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/22/2022] [Accepted: 08/03/2022] [Indexed: 10/25/2022] Open
Abstract
Boolean descriptions of gene regulatory networks can provide an insight into interactions between genes. Boolean networks hold predictive power, are easy to understand, and can be used to simulate the observed networks in different scenarios. We review fundamental and state-of-the-art methods for inference of Boolean networks. We introduce a methodology for a straightforward evaluation of Boolean inference approaches based on the generation of evaluation datasets, application of selected inference methods, and evaluation of performance measures to guide the selection of the best method for a given inference problem. We demonstrate this procedure on inference methods REVEAL (REVerse Engineering ALgorithm), Best-Fit Extension, MIBNI (Mutual Information-based Boolean Network Inference), GABNI (Genetic Algorithm-based Boolean Network Inference) and ATEN (AND/OR Tree ENsemble algorithm), which infers Boolean descriptions of gene regulatory networks from discretised time series data. Boolean inference approaches tend to perform better in terms of dynamic accuracy, and slightly worse in terms of structural correctness. We believe that the proposed methodology and provided guidelines will help researchers to develop Boolean inference approaches with a good predictive capability while maintaining structural correctness and biological relevance.
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Affiliation(s)
- Žiga Pušnik
- University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, SI-1000, Slovenia
| | - Miha Mraz
- University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, SI-1000, Slovenia
| | - Nikolaj Zimic
- University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, SI-1000, Slovenia
| | - Miha Moškon
- University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, SI-1000, Slovenia
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13
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Coleman S, Kirk PDW, Wallace C. Consensus clustering for Bayesian mixture models. BMC Bioinformatics 2022; 23:290. [PMID: 35864476 PMCID: PMC9306175 DOI: 10.1186/s12859-022-04830-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 07/05/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Cluster analysis is an integral part of precision medicine and systems biology, used to define groups of patients or biomolecules. Consensus clustering is an ensemble approach that is widely used in these areas, which combines the output from multiple runs of a non-deterministic clustering algorithm. Here we consider the application of consensus clustering to a broad class of heuristic clustering algorithms that can be derived from Bayesian mixture models (and extensions thereof) by adopting an early stopping criterion when performing sampling-based inference for these models. While the resulting approach is non-Bayesian, it inherits the usual benefits of consensus clustering, particularly in terms of computational scalability and providing assessments of clustering stability/robustness. RESULTS In simulation studies, we show that our approach can successfully uncover the target clustering structure, while also exploring different plausible clusterings of the data. We show that, when a parallel computation environment is available, our approach offers significant reductions in runtime compared to performing sampling-based Bayesian inference for the underlying model, while retaining many of the practical benefits of the Bayesian approach, such as exploring different numbers of clusters. We propose a heuristic to decide upon ensemble size and the early stopping criterion, and then apply consensus clustering to a clustering algorithm derived from a Bayesian integrative clustering method. We use the resulting approach to perform an integrative analysis of three 'omics datasets for budding yeast and find clusters of co-expressed genes with shared regulatory proteins. We validate these clusters using data external to the analysis. CONCLUSTIONS Our approach can be used as a wrapper for essentially any existing sampling-based Bayesian clustering implementation, and enables meaningful clustering analyses to be performed using such implementations, even when computational Bayesian inference is not feasible, e.g. due to poor exploration of the target density (often as a result of increasing numbers of features) or a limited computational budget that does not along sufficient samples to drawn from a single chain. This enables researchers to straightforwardly extend the applicability of existing software to much larger datasets, including implementations of sophisticated models such as those that jointly model multiple datasets.
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Affiliation(s)
- Stephen Coleman
- MRC Biostatistics Unit, University of Cambridge, Cambridge, UK
| | - Paul D. W. Kirk
- MRC Biostatistics Unit, University of Cambridge, Cambridge, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, Cambridge, UK
| | - Chris Wallace
- MRC Biostatistics Unit, University of Cambridge, Cambridge, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, Cambridge, UK
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14
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El Hadi C, Ayoub G, Bachir Y, Haykal M, Jalkh N, Kourie HR. Polygenic and Network-Based Studies in Risk Identification and Demystification of cancer. Expert Rev Mol Diagn 2022; 22:427-438. [PMID: 35400274 DOI: 10.1080/14737159.2022.2065195] [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: 11/04/2022]
Abstract
INTRODUCTION Diseases were initially thought to be the consequence of a single gene mutation. Advances in DNA sequencing tools and our understanding of gene behavior have revealed that complex diseases, such as cancer, are the product of genes cooperating with each other and with their environment in orchestrated communication networks. Seeing that the function of individual genes is still used to analyze cancer, the shift to using functionally interacting groups of genes as a new unit of study holds promise for demystifying cancer. AREAS COVERED The literature search focused on three types of cancer, namely breast, lung, and prostate, but arguments from other cancers were also included. The aim was to prove that multigene analyses can accurately predict and prognosticate cancer risk, subtype cancer for more personalized and effective treatments, and discover anti-cancer therapies. Computational intelligence is being harnessed to analyze this type of data and is proving indispensable to scientific progress. EXPERT OPINION In the future, comprehensive profiling of all kinds of patient data (e.g., serum molecules, environmental exposures) can be used to build universal networks that should help us elucidate the molecular mechanisms underlying diseases and provide appropriate preventive measures, ensuring lifelong health and longevity.
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Affiliation(s)
| | - George Ayoub
- Faculty of Medicine, Saint Joseph University, Beirut, Lebanon
| | - Yara Bachir
- Faculty of Medicine, Saint Joseph University, Beirut, Lebanon
| | - Michèle Haykal
- Faculty of Medicine, Saint Joseph University, Beirut, Lebanon
| | - Nadine Jalkh
- Medical Genetics Unit, Technology and Health division, Faculty of Medicine, Saint Joseph University, Beirut, Lebanon
| | - Hampig Raphael Kourie
- Department of Hematology-Oncology, Hotel Dieu de France University Hospital, Faculty of Medicine, Saint Joseph University, Beirut, Lebanon
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15
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Barberis M, Mondeel TD. Unveiling Forkhead-mediated regulation of yeast cell cycle and metabolic networks. Comput Struct Biotechnol J 2022; 20:1743-1751. [PMID: 35495119 PMCID: PMC9024378 DOI: 10.1016/j.csbj.2022.03.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 03/10/2022] [Accepted: 03/29/2022] [Indexed: 11/25/2022] Open
Abstract
Findings from genome-wide ChIP studies on budding yeast Forkheads are interpreted. Power, challenges and limitation of ChIP studies are presented by target gene analysis. Forkheads regulate metabolic targets through which cell division may be coordinated.
Transcription factors are regulators of the cell’s genomic landscape. By switching single genes or entire molecular pathways on or off, transcription factors modulate the precise timing of their activation. The Forkhead (Fkh) transcription factors are evolutionarily conserved to regulate organismal physiology and cell division. In addition to molecular biology and biochemical efforts, genome-wide studies have been conducted to characterize the genomic landscape potentially regulated by Forkheads in eukaryotes. Here, we discuss and interpret findings reported in six genome-wide Chromatin ImmunoPrecipitation (ChIP) studies, with a particular focus on ChIP-chip and ChIP-exo. We highlight their power and challenges to address Forkhead-mediated regulation of the cellular landscape in budding yeast. Expression changes of the targets identified in the binding assays are investigated by taking expression data for Forkhead deletion and overexpression into account. Forkheads are revealed as regulators of the metabolic network through which cell cycle dynamics may be temporally coordinated further, in addition to their well-known role as regulators of the gene cluster responsible for cell division.
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Nomoto Y, Takatsuka H, Yamada K, Suzuki T, Suzuki T, Huang Y, Latrasse D, An J, Gombos M, Breuer C, Ishida T, Maeo K, Imamura M, Yamashino T, Sugimoto K, Magyar Z, Bögre L, Raynaud C, Benhamed M, Ito M. A hierarchical transcriptional network activates specific CDK inhibitors that regulate G2 to control cell size and number in Arabidopsis. Nat Commun 2022; 13:1660. [PMID: 35351906 PMCID: PMC8964727 DOI: 10.1038/s41467-022-29316-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 03/07/2022] [Indexed: 12/13/2022] Open
Abstract
AbstractHow cell size and number are determined during organ development remains a fundamental question in cell biology. Here, we identified a GRAS family transcription factor, called SCARECROW-LIKE28 (SCL28), with a critical role in determining cell size in Arabidopsis. SCL28 is part of a transcriptional regulatory network downstream of the central MYB3Rs that regulate G2 to M phase cell cycle transition. We show that SCL28 forms a dimer with the AP2-type transcription factor, AtSMOS1, which defines the specificity for promoter binding and directly activates transcription of a specific set of SIAMESE-RELATED (SMR) family genes, encoding plant-specific inhibitors of cyclin-dependent kinases and thus inhibiting cell cycle progression at G2 and promoting the onset of endoreplication. Through this dose-dependent regulation of SMR transcription, SCL28 quantitatively sets the balance between cell size and number without dramatically changing final organ size. We propose that this hierarchical transcriptional network constitutes a cell cycle regulatory mechanism that allows to adjust cell size and number to attain robust organ growth.
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17
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The microprotein Nrs1 rewires the G1/S transcriptional machinery during nitrogen limitation in budding yeast. PLoS Biol 2022; 20:e3001548. [PMID: 35239649 PMCID: PMC8893695 DOI: 10.1371/journal.pbio.3001548] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 01/19/2022] [Indexed: 12/01/2022] Open
Abstract
Commitment to cell division at the end of G1 phase, termed Start in the budding yeast Saccharomyces cerevisiae, is strongly influenced by nutrient availability. To identify new dominant activators of Start that might operate under different nutrient conditions, we screened a genome-wide ORF overexpression library for genes that bypass a Start arrest caused by absence of the G1 cyclin Cln3 and the transcriptional activator Bck2. We recovered a hypothetical gene YLR053c, renamed NRS1 for Nitrogen-Responsive Start regulator 1, which encodes a poorly characterized 108 amino acid microprotein. Endogenous Nrs1 was nuclear-localized, restricted to poor nitrogen conditions, induced upon TORC1 inhibition, and cell cycle-regulated with a peak at Start. NRS1 interacted genetically with SWI4 and SWI6, which encode subunits of the main G1/S transcription factor complex SBF. Correspondingly, Nrs1 physically interacted with Swi4 and Swi6 and was localized to G1/S promoter DNA. Nrs1 exhibited inherent transactivation activity, and fusion of Nrs1 to the SBF inhibitor Whi5 was sufficient to suppress other Start defects. Nrs1 appears to be a recently evolved microprotein that rewires the G1/S transcriptional machinery under poor nitrogen conditions. Commitment to cell division at the end of G1 phase in the budding yeast Saccharomyces cerevisiae is strongly influenced by nutrient availability. This study identifies a micro-protein that promotes G1/S transcription activation and cell cycle entry in yeast under nitrogen-limited conditions.
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18
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Ali O, Farooq A, Yang M, Jin VX, Bjørås M, Wang J. abc4pwm: affinity based clustering for position weight matrices in applications of DNA sequence analysis. BMC Bioinformatics 2022; 23:83. [PMID: 35240993 PMCID: PMC8896320 DOI: 10.1186/s12859-022-04615-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 02/18/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transcription factor (TF) binding motifs are identified by high throughput sequencing technologies as means to capture Protein-DNA interactions. These motifs are often represented by consensus sequences in form of position weight matrices (PWMs). With ever-increasing pool of TF binding motifs from multiple sources, redundancy issues are difficult to avoid, especially when every source maintains its own database for collection. One solution can be to cluster biologically relevant or similar PWMs, whether coming from experimental detection or in silico predictions. However, there is a lack of efficient tools to cluster PWMs. Assessing quality of PWM clusters is yet another challenge. Therefore, new methods and tools are required to efficiently cluster PWMs and assess quality of clusters. RESULTS A new Python package Affinity Based Clustering for Position Weight Matrices (abc4pwm) was developed. It efficiently clustered PWMs from multiple sources with or without using DNA-Binding Domain (DBD) information, generated a representative motif for each cluster, evaluated the clustering quality automatically, and filtered out incorrectly clustered PWMs. Additionally, it was able to update human DBD family database automatically, classified known human TF PWMs to the respective DBD family, and performed TF motif searching and motif discovery by a new ensemble learning approach. CONCLUSION This work demonstrates applications of abc4pwm in the DNA sequence analysis for various high throughput sequencing data using ~ 1770 human TF PWMs. It recovered known TF motifs at gene promoters based on gene expression profiles (RNA-seq) and identified true TF binding targets for motifs predicted from ChIP-seq experiments. Abc4pwm is a useful tool for TF motif searching, clustering, quality assessment and integration in multiple types of sequence data analysis including RNA-seq, ChIP-seq and ATAC-seq.
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Affiliation(s)
- Omer Ali
- Department of Pathology, Oslo University Hospital - Norwegian Radium Hospital, Oslo, Norway
| | - Amna Farooq
- Department of Pathology, Oslo University Hospital - Norwegian Radium Hospital, Oslo, Norway
| | - Mingyi Yang
- Department of Medical Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway.,Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Victor X Jin
- Department of Molecular Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Magnar Bjørås
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Junbai Wang
- Department of Clinical Molecular Biology, Institute of Clinical Medicine, University of Oslo, Oslo, Norway. .,Department of Clinical Molecular Biology (EpiGen), Akershus University Hospital, Lørenskog, Norway.
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Cyclin-Dependent Kinases and CTD Phosphatases in Cell Cycle Transcriptional Control: Conservation across Eukaryotic Kingdoms and Uniqueness to Plants. Cells 2022; 11:cells11020279. [PMID: 35053398 PMCID: PMC8774115 DOI: 10.3390/cells11020279] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/08/2022] [Accepted: 01/10/2022] [Indexed: 02/04/2023] Open
Abstract
Cell cycle control is vital for cell proliferation in all eukaryotic organisms. The entire cell cycle can be conceptually separated into four distinct phases, Gap 1 (G1), DNA synthesis (S), G2, and mitosis (M), which progress sequentially. The precise control of transcription, in particular, at the G1 to S and G2 to M transitions, is crucial for the synthesis of many phase-specific proteins, to ensure orderly progression throughout the cell cycle. This mini-review highlights highly conserved transcriptional regulators that are shared in budding yeast (Saccharomyces cerevisiae), Arabidopsis thaliana model plant, and humans, which have been separated for more than a billion years of evolution. These include structurally and/or functionally conserved regulators cyclin-dependent kinases (CDKs), RNA polymerase II C-terminal domain (CTD) phosphatases, and the classical versus shortcut models of Pol II transcriptional control. A few of CDKs and CTD phosphatases counteract to control the Pol II CTD Ser phosphorylation codes and are considered critical regulators of Pol II transcriptional process from initiation to elongation and termination. The functions of plant-unique CDKs and CTD phosphatases in relation to cell division are also briefly summarized. Future studies towards testing a cooperative transcriptional mechanism, which is proposed here and involves sequence-specific transcription factors and the shortcut model of Pol II CTD code modulation, across the three eukaryotic kingdoms will reveal how individual organisms achieve the most productive, large-scale transcription of phase-specific genes required for orderly progression throughout the entire cell cycle.
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20
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Cyclin/Forkhead-mediated coordination of cyclin waves: an autonomous oscillator rationalizing the quantitative model of Cdk control for budding yeast. NPJ Syst Biol Appl 2021; 7:48. [PMID: 34903735 PMCID: PMC8668886 DOI: 10.1038/s41540-021-00201-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 11/01/2021] [Indexed: 01/21/2023] Open
Abstract
Networks of interacting molecules organize topology, amount, and timing of biological functions. Systems biology concepts required to pin down 'network motifs' or 'design principles' for time-dependent processes have been developed for the cell division cycle, through integration of predictive computer modeling with quantitative experimentation. A dynamic coordination of sequential waves of cyclin-dependent kinases (cyclin/Cdk) with the transcription factors network offers insights to investigate how incompatible processes are kept separate in time during the eukaryotic cell cycle. Here this coordination is discussed for the Forkhead transcription factors in light of missing gaps in the current knowledge of cell cycle control in budding yeast. An emergent design principle is proposed where cyclin waves are synchronized by a cyclin/Cdk-mediated feed-forward regulation through the Forkhead as a transcriptional timer. This design is rationalized by the bidirectional interaction between mitotic cyclins and the Forkhead transcriptional timer, resulting in an autonomous oscillator that may be instrumental for a well-timed progression throughout the cell cycle. The regulation centered around the cyclin/Cdk-Forkhead axis can be pivotal to timely coordinate cell cycle dynamics, thereby to actuate the quantitative model of Cdk control.
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21
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Extensive Translational Regulation through the Proliferative Transition of Trypanosoma cruzi Revealed by Multi-Omics. mSphere 2021; 6:e0036621. [PMID: 34468164 PMCID: PMC8550152 DOI: 10.1128/msphere.00366-21] [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] [Indexed: 12/28/2022] Open
Abstract
Trypanosoma cruzi is the etiological agent for Chagas disease, a neglected parasitic disease in Latin America. Gene transcription control governs the eukaryotic cell replication but is absent in trypanosomatids; thus, it must be replaced by posttranscriptional regulatory events. We investigated the entrance into the T. cruzi replicative cycle using ribosome profiling and proteomics on G1/S epimastigote cultures synchronized with hydroxyurea. We identified 1,784 translationally regulated genes (change > 2, false-discovery rate [FDR] < 0.05) and 653 differentially expressed proteins (change > 1.5, FDR < 0.05), respectively. A major translational remodeling accompanied by an extensive proteome change is found, while the transcriptome remains largely unperturbed at the replicative entrance of the cell cycle. The differentially expressed genes comprise specific cell cycle processes, confirming previous findings while revealing candidate cell cycle regulators that undergo previously unnoticed translational regulation. Clusters of genes showing a coordinated regulation at translation and protein abundance share related biological functions such as cytoskeleton organization and mitochondrial metabolism; thus, they may represent posttranscriptional regulons. The translatome and proteome of the coregulated clusters change in both coupled and uncoupled directions, suggesting that complex cross talk between the two processes is required to achieve adequate protein levels of different regulons. This is the first simultaneous assessment of the transcriptome, translatome, and proteome of trypanosomatids, which represent a paradigm for the absence of transcriptional control. The findings suggest that gene expression chronology along the T. cruzi cell cycle is controlled mainly by translatome and proteome changes coordinated using different mechanisms for specific gene groups. IMPORTANCE Trypanosoma cruzi is an ancient eukaryotic unicellular parasite causing Chagas disease, a potentially life-threatening illness that affects 6 to 7 million people, mostly in Latin America. The antiparasitic treatments for the disease have incomplete efficacy and adverse reactions; thus, improved drugs are needed. We study the mechanisms governing the replication of the parasite, aiming to find differences with the human host, valuable for the development of parasite-specific antiproliferative drugs. Transcriptional regulation is essential for replication in most eukaryotes, but in trypanosomatids, it must be replaced by subsequent gene regulation steps since they lack transcription initiation control. We identified the genome-wide remodeling of mRNA translation and protein abundance during the entrance to the replicative phase of the cell cycle. We found that translation is strongly regulated, causing variation in protein levels of specific cell cycle processes, representing the first simultaneous study of the translatome and proteome in trypanosomatids.
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22
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Fu L, Li J, Wang YG. Robust approach for variable selection with high dimensional longitudinal data analysis. Stat Med 2021; 40:6835-6854. [PMID: 34619808 DOI: 10.1002/sim.9213] [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: 11/23/2020] [Revised: 08/14/2021] [Accepted: 09/16/2021] [Indexed: 11/06/2022]
Abstract
This article proposes a new robust smooth-threshold estimating equation to select important variables and automatically estimate parameters for high dimensional longitudinal data. A novel working correlation matrix is proposed to capture correlations within the same subject. The proposed procedure works well when the number of covariates p n increases as the number of subjects n increases. The proposed estimates are competitive with the estimates obtained with the true correlation structure, especially when the data are contaminated. Moreover, the proposed method is robust against outliers in the response variables and/or covariates. Furthermore, the oracle properties for robust smooth-threshold estimating equations under "large n, diverging p n " are established under some regularity conditions. Extensive simulation studies and a yeast cell cycle data are used to evaluate the performance of the proposed method, and results show that the proposed method is competitive with existing robust variable selection procedures.
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Affiliation(s)
- Liya Fu
- School of Mathematics and Statistics, Xi'an Jiaotong University, Xi'an, China
| | - Jiaqi Li
- School of Mathematics and Statistics, Xi'an Jiaotong University, Xi'an, China
| | - You-Gan Wang
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
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23
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Mofatteh M, Echegaray-Iturra F, Alamban A, Dalla Ricca F, Bakshi A, Aydogan MG. Autonomous clocks that regulate organelle biogenesis, cytoskeletal organization, and intracellular dynamics. eLife 2021; 10:e72104. [PMID: 34586070 PMCID: PMC8480978 DOI: 10.7554/elife.72104] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/14/2021] [Indexed: 12/27/2022] Open
Abstract
How do cells perceive time? Do cells use temporal information to regulate the production/degradation of their enzymes, membranes, and organelles? Does controlling biological time influence cytoskeletal organization and cellular architecture in ways that confer evolutionary and physiological advantages? Potential answers to these fundamental questions of cell biology have historically revolved around the discussion of 'master' temporal programs, such as the principal cyclin-dependent kinase/cyclin cell division oscillator and the circadian clock. In this review, we provide an overview of the recent evidence supporting an emerging concept of 'autonomous clocks,' which under normal conditions can be entrained by the cell cycle and/or the circadian clock to run at their pace, but can also run independently to serve their functions if/when these major temporal programs are halted/abrupted. We begin the discussion by introducing recent developments in the study of such clocks and their roles at different scales and complexities. We then use current advances to elucidate the logic and molecular architecture of temporal networks that comprise autonomous clocks, providing important clues as to how these clocks may have evolved to run independently and, sometimes at the cost of redundancy, have strongly coupled to run under the full command of the cell cycle and/or the circadian clock. Next, we review a list of important recent findings that have shed new light onto potential hallmarks of autonomous clocks, suggestive of prospective theoretical and experimental approaches to further accelerate their discovery. Finally, we discuss their roles in health and disease, as well as possible therapeutic opportunities that targeting the autonomous clocks may offer.
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Affiliation(s)
- Mohammad Mofatteh
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
| | - Fabio Echegaray-Iturra
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
| | - Andrew Alamban
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
| | - Francesco Dalla Ricca
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
| | - Anand Bakshi
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
| | - Mustafa G Aydogan
- Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
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24
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Bhagwat M, Nagar S, Kaur P, Mehta R, Vancurova I, Vancura A. Replication stress inhibits synthesis of histone mRNAs in yeast by removing Spt10p and Spt21p from the histone promoters. J Biol Chem 2021; 297:101246. [PMID: 34582893 PMCID: PMC8551654 DOI: 10.1016/j.jbc.2021.101246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/17/2021] [Accepted: 09/23/2021] [Indexed: 12/27/2022] Open
Abstract
Proliferating cells coordinate histone and DNA synthesis to maintain correct stoichiometry for chromatin assembly. Histone mRNA levels must be repressed when DNA replication is inhibited to prevent toxicity and genome instability due to free non-chromatinized histone proteins. In mammalian cells, replication stress triggers degradation of histone mRNAs, but it is unclear if this mechanism is conserved from other species. The aim of this study was to identify the histone mRNA decay pathway in the yeast Saccharomyces cerevisiae and determine the mechanism by which DNA replication stress represses histone mRNAs. Using reverse transcription-quantitative PCR and chromatin immunoprecipitation–quantitative PCR, we show here that histone mRNAs can be degraded by both 5′ → 3′ and 3′ → 5′ pathways; however, replication stress does not trigger decay of histone mRNA in yeast. Rather, replication stress inhibits transcription of histone genes by removing the histone gene–specific transcription factors Spt10p and Spt21p from histone promoters, leading to disassembly of the preinitiation complexes and eviction of RNA Pol II from histone genes by a mechanism facilitated by checkpoint kinase Rad53p and histone chaperone Asf1p. In contrast, replication stress does not remove SCB-binding factor transcription complex, another activator of histone genes, from the histone promoters, suggesting that Spt10p and Spt21p have unique roles in the transcriptional downregulation of histone genes during replication stress. Together, our data show that, unlike in mammalian cells, replication stress in yeast does not trigger decay of histone mRNAs but inhibits histone transcription.
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Affiliation(s)
- Madhura Bhagwat
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Shreya Nagar
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Pritpal Kaur
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Riddhi Mehta
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Ivana Vancurova
- Department of Biological Sciences, St John's University, Queens, New York, USA
| | - Ales Vancura
- Department of Biological Sciences, St John's University, Queens, New York, USA.
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25
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Huffaker TB, Ekiz HA, Barba C, Lee SH, Runtsch MC, Nelson MC, Bauer KM, Tang WW, Mosbruger TL, Cox JE, Round JL, Voth WP, O'Connell RM. A Stat1 bound enhancer promotes Nampt expression and function within tumor associated macrophages. Nat Commun 2021; 12:2620. [PMID: 33976173 PMCID: PMC8113251 DOI: 10.1038/s41467-021-22923-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 03/30/2021] [Indexed: 02/03/2023] Open
Abstract
Tumor associated macrophage responses are regulated by distinct metabolic states that affect their function. However, the ability of specific signals in the local tumor microenvironment to program macrophage metabolism remains under investigation. Here, we identify NAMPT, the rate limiting enzyme in NAD salvage synthesis, as a target of STAT1 during cellular activation by interferon gamma, an important driver of macrophage polarization and antitumor responses. We demonstrate that STAT1 occupies a conserved element within the first intron of Nampt, termed Nampt-Regulatory Element-1 (NRE1). Through disruption of NRE1 or pharmacological inhibition, a subset of M1 genes is sensitive to NAMPT activity through its impact on glycolytic processes. scRNAseq is used to profile in vivo responses by NRE1-deficient, tumor-associated leukocytes in melanoma tumors through the creation of a unique mouse strain. Reduced Nampt and inflammatory gene expression are present in specific myeloid and APC populations; moreover, targeted ablation of NRE1 in macrophage lineages results in greater tumor burden. Finally, elevated NAMPT expression correlates with IFNγ responses and melanoma patient survival. This study identifies IFN and STAT1-inducible Nampt as an important factor that shapes the metabolic program and function of tumor associated macrophages.
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Affiliation(s)
- Thomas B Huffaker
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - H Atakan Ekiz
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Cindy Barba
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Soh-Hyun Lee
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Marah C Runtsch
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Morgan C Nelson
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Kaylyn M Bauer
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - William W Tang
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | | | - James E Cox
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
- Metabolomics Core Research Facility, University of Utah, Salt Lake City, UT, USA
| | - June L Round
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Warren P Voth
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA.
| | - Ryan M O'Connell
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, UT, USA.
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA.
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26
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Hackett SR, Baltz EA, Coram M, Wranik BJ, Kim G, Baker A, Fan M, Hendrickson DG, Berndl M, McIsaac RS. Learning causal networks using inducible transcription factors and transcriptome-wide time series. Mol Syst Biol 2021; 16:e9174. [PMID: 32181581 PMCID: PMC7076914 DOI: 10.15252/msb.20199174] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 02/13/2020] [Accepted: 02/19/2020] [Indexed: 11/27/2022] Open
Abstract
We present IDEA (the Induction Dynamics gene Expression Atlas), a dataset constructed by independently inducing hundreds of transcription factors (TFs) and measuring timecourses of the resulting gene expression responses in budding yeast. Each experiment captures a regulatory cascade connecting a single induced regulator to the genes it causally regulates. We discuss the regulatory cascade of a single TF, Aft1, in detail; however, IDEA contains > 200 TF induction experiments with 20 million individual observations and 100,000 signal‐containing dynamic responses. As an application of IDEA, we integrate all timecourses into a whole‐cell transcriptional model, which is used to predict and validate multiple new and underappreciated transcriptional regulators. We also find that the magnitudes of coefficients in this model are predictive of genetic interaction profile similarities. In addition to being a resource for exploring regulatory connectivity between TFs and their target genes, our modeling approach shows that combining rapid perturbations of individual genes with genome‐scale time‐series measurements is an effective strategy for elucidating gene regulatory networks.
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Affiliation(s)
| | | | | | | | - Griffin Kim
- Calico Life Sciences LLC, South San Francisco, CA, USA
| | - Adam Baker
- Calico Life Sciences LLC, South San Francisco, CA, USA
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27
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Zhang MQ. A personal journey on cracking the genomic codes. QUANTITATIVE BIOLOGY 2021. [DOI: 10.15302/j-qb-021-0245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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28
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Barman S, Kwon YK. A neuro-evolution approach to infer a Boolean network from time-series gene expressions. Bioinformatics 2020; 36:i762-i769. [PMID: 33381823 DOI: 10.1093/bioinformatics/btaa840] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2020] [Indexed: 11/14/2022] Open
Abstract
SUMMARY In systems biology, it is challenging to accurately infer a regulatory network from time-series gene expression data, and a variety of methods have been proposed. Most of them were computationally inefficient in inferring very large networks, though, because of the increasing number of candidate regulatory genes. Although a recent approach called GABNI (genetic algorithm-based Boolean network inference) was presented to resolve this problem using a genetic algorithm, there is room for performance improvement because it employed a limited representation model of regulatory functions.In this regard, we devised a novel genetic algorithm combined with a neural network for the Boolean network inference, where a neural network is used to represent the regulatory function instead of an incomplete Boolean truth table used in the GABNI. In addition, our new method extended the range of the time-step lag parameter value between the regulatory and the target genes for more flexible representation of the regulatory function. Extensive simulations with the gene expression datasets of the artificial and real networks were conducted to compare our method with five well-known existing methods including GABNI. Our proposed method significantly outperformed them in terms of both structural and dynamics accuracy. CONCLUSION Our method can be a promising tool to infer a large-scale Boolean regulatory network from time-series gene expression data. AVAILABILITY AND IMPLEMENTATION The source code is freely available at https://github.com/kwon-uou/NNBNI. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Shohag Barman
- Department of Computer Science, American International University-Bangladesh (AIUB), Dhaka 1229, Bangladesh
| | - Yung-Keun Kwon
- School of IT Convergence, University of Ulsan, Ulsan 44610, Republic of Korea
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29
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Yu Y, Yarrington RM, Stillman DJ. FACT and Ash1 promote long-range and bidirectional nucleosome eviction at the HO promoter. Nucleic Acids Res 2020; 48:10877-10889. [PMID: 33010153 PMCID: PMC7641740 DOI: 10.1093/nar/gkaa819] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/07/2020] [Accepted: 09/25/2020] [Indexed: 11/14/2022] Open
Abstract
The Saccharomyces cerevisiae HO gene is a model regulatory system with complex transcriptional regulation. Budding yeast divide asymmetrically and HO is expressed only in mother cells where a nucleosome eviction cascade along the promoter during the cell cycle enables activation. HO expression in daughter cells is inhibited by high concentration of Ash1 in daughters. To understand how Ash1 represses transcription, we used a myo4 mutation which boosts Ash1 accumulation in both mothers and daughters and show that Ash1 inhibits promoter recruitment of SWI/SNF and Gcn5. We show Ash1 is also required for the efficient nucleosome repopulation that occurs after eviction, and the strongest effects of Ash1 are seen when Ash1 has been degraded and at promoter locations distant from where Ash1 bound. Additionally, we defined a specific nucleosome/nucleosome-depleted region structure that restricts HO activation to one of two paralogous DNA-binding factors. We also show that nucleosome eviction occurs bidirectionally over a large distance. Significantly, eviction of the more distant nucleosomes is dependent upon the FACT histone chaperone, and FACT is recruited to these regions when eviction is beginning. These last observations, along with ChIP experiments involving the SBF factor, suggest a long-distance loop transiently forms at the HO promoter.
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Affiliation(s)
- Yaxin Yu
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Robert M Yarrington
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - David J Stillman
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
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30
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Lopes A, Magrinelli E, Telley L. Emerging Roles of Single-Cell Multi-Omics in Studying Developmental Temporal Patterning. Int J Mol Sci 2020; 21:E7491. [PMID: 33050604 PMCID: PMC7589732 DOI: 10.3390/ijms21207491] [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: 09/16/2020] [Revised: 10/06/2020] [Accepted: 10/08/2020] [Indexed: 01/16/2023] Open
Abstract
The complexity of brain structure and function is rooted in the precise spatial and temporal regulation of selective developmental events. During neurogenesis, both vertebrates and invertebrates generate a wide variety of specialized cell types through the expansion and specification of a restricted set of neuronal progenitors. Temporal patterning of neural progenitors rests on fine regulation between cell-intrinsic and cell-extrinsic mechanisms. The rapid emergence of high-throughput single-cell technologies combined with elaborate computational analysis has started to provide us with unprecedented biological insights related to temporal patterning in the developing central nervous system (CNS). Here, we present an overview of recent advances in Drosophila and vertebrates, focusing both on cell-intrinsic mechanisms and environmental influences. We then describe the various multi-omics approaches that have strongly contributed to our current understanding and discuss perspectives on the various -omics approaches that hold great potential for the future of temporal patterning research.
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Affiliation(s)
| | | | - Ludovic Telley
- Department of Basic Neuroscience, University of Lausanne, 1005 Lausanne, Switzerland; (A.L.); (E.M.)
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31
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Liu J, Shively CA, Mitra RD. Quantitative analysis of transcription factor binding and expression using calling cards reporter arrays. Nucleic Acids Res 2020; 48:e50. [PMID: 32133534 PMCID: PMC7229839 DOI: 10.1093/nar/gkaa141] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 01/31/2020] [Accepted: 02/25/2020] [Indexed: 12/13/2022] Open
Abstract
We report a tool, Calling Cards Reporter Arrays (CCRA), that measures transcription factor (TF) binding and the consequences on gene expression for hundreds of synthetic promoters in yeast. Using Cbf1p and MAX, we demonstrate that the CCRA method is able to detect small changes in binding free energy with a sensitivity comparable to in vitro methods, enabling the measurement of energy landscapes in vivo. We then demonstrate the quantitative analysis of cooperative interactions by measuring Cbf1p binding at synthetic promoters with multiple sites. We find that the cooperativity between Cbf1p dimers varies sinusoidally with a period of 10.65 bp and energetic cost of 1.37 KBT for sites that are positioned ‘out of phase’. Finally, we characterize the binding and expression of a group of TFs, Tye7p, Gcr1p and Gcr2p, that act together as a ‘TF collective’, an important but poorly characterized model of TF cooperativity. We demonstrate that Tye7p often binds promoters without its recognition site because it is recruited by other collective members, whereas these other members require their recognition sites, suggesting a hierarchy where these factors recruit Tye7p but not vice versa. Our experiments establish CCRA as a useful tool for quantitative investigations into TF binding and function.
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Affiliation(s)
- Jiayue Liu
- Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA.,The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA
| | - Christian A Shively
- Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA.,The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA
| | - Robi D Mitra
- Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA.,The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA.,McDonnell Genome Institute, Washington University School of Medicine in St. Louis, St. Louis, MO 63108, USA
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32
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Black L, Tollis S, Fu G, Fiche JB, Dorsey S, Cheng J, Ghazal G, Notley S, Crevier B, Bigness J, Nollmann M, Tyers M, Royer CA. G1/S transcription factors assemble in increasing numbers of discrete clusters through G1 phase. J Cell Biol 2020; 219:151997. [PMID: 32744610 PMCID: PMC7480102 DOI: 10.1083/jcb.202003041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/20/2020] [Accepted: 05/26/2020] [Indexed: 02/03/2023] Open
Abstract
In budding yeast, the transcription factors SBF and MBF activate a large program of gene expression in late G1 phase that underlies commitment to cell division, termed Start. SBF/MBF are limiting with respect to target promoters in small G1 phase cells and accumulate as cells grow, raising the questions of how SBF/MBF are dynamically distributed across the G1/S regulon and how this impacts the Start transition. Super-resolution Photo-Activatable Localization Microscopy (PALM) mapping of the static positions of SBF/MBF subunits in fixed cells revealed each transcription factor was organized into discrete clusters containing approximately eight copies regardless of cell size and that the total number of clusters increased as cells grew through G1 phase. Stochastic modeling using reasonable biophysical parameters recapitulated growth-dependent SBF/MBF clustering and predicted TF dynamics that were confirmed in live cell PALM experiments. This spatio-temporal organization of SBF/MBF may help coordinate activation of G1/S regulon and the Start transition.
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Affiliation(s)
- Labe Black
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
| | - Sylvain Tollis
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Canada
| | - Guo Fu
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
| | - Jean-Bernard Fiche
- Centre de Biochimie Structurale, Centre National de la Recherche Scientifique UMR5048, Institut National de la Santé et de la Recherche Médicale U1054, Université de Montpellier, Montpellier, France
| | - Savanna Dorsey
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
| | - Jing Cheng
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Canada
| | - Ghada Ghazal
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Canada
| | - Stephen Notley
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
| | - Benjamin Crevier
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
| | - Jeremy Bigness
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
| | - Marcelo Nollmann
- Centre de Biochimie Structurale, Centre National de la Recherche Scientifique UMR5048, Institut National de la Santé et de la Recherche Médicale U1054, Université de Montpellier, Montpellier, France
| | - Mike Tyers
- Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, Canada
| | - Catherine Ann Royer
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY
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33
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Liang C, Ding S, Sun W, Liu L, Zhao W, Zhang D, Ying H, Liu D, Chen Y. Biofilm-based fermentation: a novel immobilisation strategy for Saccharomyces cerevisiae cell cycle progression during ethanol production. Appl Microbiol Biotechnol 2020; 104:7495-7505. [PMID: 32666184 DOI: 10.1007/s00253-020-10770-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 06/07/2020] [Accepted: 07/02/2020] [Indexed: 12/11/2022]
Abstract
Biofilm-based fermentation, as a new immobilisation strategy, is beneficial for industrial fermentation due to its excellent environmental resistance, high productivity and continuous fermentation relative to calcium alginate-immobilised fermentation. These two techniques differ mainly regarding cell stages. Here, we describe the cell phenotype of Saccharomyces cerevisiae biofilm-based fermentation and compare cell cycle stages with those during immobilisation in calcium alginate. Most cells in the biofilm-based fermentation adhered to the cotton-fibre carrier of the biofilm and were in the G2/M phase whereas alginate-embedded cells were in the G1/G0 phase. Deletion of the RIM15 gene, which regulates cell cycle progression according to nutritional status, hampered the cell cycle arrest observed in alginate-embedded cells, enhanced biofilm formation and improved fermentation ability. The improved biofilm formation shown by the rim15△ strain could be attributed to an increase in the expression level of the adhesion protein FLO11 and synthesis of trehalose. These findings suggest that the extracellular environment is mainly responsible for the difference between biofilm-based fermentation and alginate-embedded fermentation, and that RIM15 plays an essential role in cell cycle progression. KEY POINTS: • In the biofilm, S. cerevisiae cell populations were mostly in the G2/M phase while alginate-embedded cells were arrested in the G1/G0 phase. • The RIM15 gene partially influenced the cell cycle progression observed during ethanol fermentation. • Biofilm-based cells were actively adsorbed on the physical carrier. • Biofilm immobilisation could maintain cell division activity explaining its fermentation efficiency.
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Affiliation(s)
- Caice Liang
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Sai Ding
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Wenjun Sun
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Li Liu
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Wei Zhao
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Deli Zhang
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Hanjie Ying
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, 450000, China
| | - Dong Liu
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, 450000, China
| | - Yong Chen
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China. .,State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
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34
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Liu Q, Zhu X, Lindström M, Shi Y, Zheng J, Hao X, Gustafsson CM, Liu B. Yeast mismatch repair components are required for stable inheritance of gene silencing. PLoS Genet 2020; 16:e1008798. [PMID: 32469861 PMCID: PMC7286534 DOI: 10.1371/journal.pgen.1008798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 06/10/2020] [Accepted: 04/26/2020] [Indexed: 11/19/2022] Open
Abstract
Alterations in epigenetic silencing have been associated with ageing and tumour formation. Although substantial efforts have been made towards understanding the mechanisms of gene silencing, novel regulators in this process remain to be identified. To systematically search for components governing epigenetic silencing, we developed a genome-wide silencing screen for yeast (Saccharomyces cerevisiae) silent mating type locus HMR. Unexpectedly, the screen identified the mismatch repair (MMR) components Pms1, Mlh1, and Msh2 as being required for silencing at this locus. We further found that the identified genes were also required for proper silencing in telomeres. More intriguingly, the MMR mutants caused a redistribution of Sir2 deacetylase, from silent mating type loci and telomeres to rDNA regions. As a consequence, acetylation levels at histone positions H3K14, H3K56, and H4K16 were increased at silent mating type loci and telomeres but were decreased in rDNA regions. Moreover, knockdown of MMR components in human HEK293T cells increased subtelomeric DUX4 gene expression. Our work reveals that MMR components are required for stable inheritance of gene silencing patterns and establishes a link between the MMR machinery and the control of epigenetic silencing.
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Affiliation(s)
- Qian Liu
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan, Goteborg, Sweden
| | - Xuefeng Zhu
- Institute of Biomedicine, University of Gothenburg, Goteborg, Sweden
- * E-mail: (XZ); (BL)
| | - Michelle Lindström
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan, Goteborg, Sweden
| | - Yonghong Shi
- Institute of Biomedicine, University of Gothenburg, Goteborg, Sweden
| | - Ju Zheng
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan, Goteborg, Sweden
- Department of Biology, Functional Biology, KU Leuven, Heverlee, Belgium
| | - Xinxin Hao
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan, Goteborg, Sweden
| | | | - Beidong Liu
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan, Goteborg, Sweden
- Center for Large-scale cell-based screening, Faculty of Science, University of Gothenburg, Medicinaregatan, Goteborg, Sweden
- * E-mail: (XZ); (BL)
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35
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Zhao Y, Wang D, Zhang Z, Lu Y, Yang X, Ouyang Q, Tang C, Li F. Critical slowing down and attractive manifold: A mechanism for dynamic robustness in the yeast cell-cycle process. Phys Rev E 2020; 101:042405. [PMID: 32422801 DOI: 10.1103/physreve.101.042405] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 01/13/2020] [Indexed: 11/07/2022]
Abstract
Biological processes that execute complex multiple functions, such as the cell cycle, must ensure the order of sequential events and maintain dynamic robustness against various fluctuations. Here, we examine the mechanisms and fundamental structure that achieve these properties in the cell cycle of the budding yeast Saccharomyces cerevisiae. We show that this process behaves like an excitable system containing three well-decoupled saddle-node bifurcations to execute DNA replication and mitosis events. The yeast cell-cycle regulatory network can be divided into three modules-the G1/S phase, early M phase, and late M phase-wherein both positive feedback loops in each module and interactions among modules play important roles. Specifically, when the cell-cycle process operates near the critical points of the saddle-node bifurcations, a critical slowing down effect takes place. Such interregnum then allows for an attractive manifold and sufficient duration for cell-cycle events, within which to assess the completion of DNA replication and mitosis, e.g., spindle assembly. Moreover, such arrangement ensures that any fluctuation in an early module or event will not transmit to a later module or event. Thus, our results suggest a possible dynamical mechanism of the cell-cycle process to ensure event order and dynamic robustness and give insight into the evolution of eukaryotic cell-cycle processes.
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Affiliation(s)
- Yao Zhao
- School of Physics, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Dedi Wang
- School of Physics, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Zhiwen Zhang
- School of Physics, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Ying Lu
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Xiaojing Yang
- Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Qi Ouyang
- School of Physics, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Chao Tang
- School of Physics, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Fangting Li
- School of Physics, Peking University, Beijing 100871, China.,Center for Quantitative Biology, Peking University, Beijing 100871, China
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36
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Fei Q, Zou Z, Roundtree IA, Sun HL, He C. YTHDF2 promotes mitotic entry and is regulated by cell cycle mediators. PLoS Biol 2020; 18:e3000664. [PMID: 32267835 PMCID: PMC7170294 DOI: 10.1371/journal.pbio.3000664] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 04/20/2020] [Accepted: 03/20/2020] [Indexed: 11/19/2022] Open
Abstract
The N6-methyladenosine (m6A) modification regulates mRNA stability and translation. Here, we show that transcriptomic m6A modification can be dynamic and the m6A reader protein YTH N6-methyladenosine RNA binding protein 2 (YTHDF2) promotes mRNA decay during cell cycle. Depletion of YTHDF2 in HeLa cells leads to the delay of mitotic entry due to overaccumulation of negative regulators of cell cycle such as Wee1-like protein kinase (WEE1). We demonstrate that WEE1 transcripts contain m6A modification, which promotes their decay through YTHDF2. Moreover, we found that YTHDF2 protein stability is dependent on cyclin-dependent kinase 1 (CDK1) activity. Thus, CDK1, YTHDF2, and WEE1 form a feedforward regulatory loop to promote mitotic entry. We further identified Cullin 1 (CUL1), Cullin 4A (CUL4A), damaged DNA-binding protein 1 (DDB1), and S-phase kinase-associated protein 2 (SKP2) as components of E3 ubiquitin ligase complexes that mediate YTHDF2 proteolysis. Our study provides insights into how cell cycle mediators modulate transcriptomic m6A modification, which in turn regulates the cell cycle.
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Affiliation(s)
- Qili Fei
- Department of Chemistry, The University of Chicago, Chicago, Illinois, United States of America
- Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois, United States of America
- Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, Guangdong, China
| | - Zhongyu Zou
- Department of Chemistry, The University of Chicago, Chicago, Illinois, United States of America
- Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois, United States of America
| | - Ian A. Roundtree
- Department of Chemistry, The University of Chicago, Chicago, Illinois, United States of America
- Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois, United States of America
- Medical Scientist Training Program, The University of Chicago, Chicago, Illinois, United States of America
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois, United States of America
- Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois, United States of America
| | - Hui-Lung Sun
- Department of Chemistry, The University of Chicago, Chicago, Illinois, United States of America
- Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois, United States of America
| | - Chuan He
- Department of Chemistry, The University of Chicago, Chicago, Illinois, United States of America
- Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois, United States of America
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois, United States of America
- Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois, United States of America
- * E-mail:
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37
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Chen H, Maduranga DAK, Mundra PA, Zheng J. Bayesian Data Fusion of Gene Expression and Histone Modification Profiles for Inference of Gene Regulatory Network. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2020; 17:516-525. [PMID: 30207963 DOI: 10.1109/tcbb.2018.2869590] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Accurately reconstructing gene regulatory networks (GRNs) from high-throughput gene expression data has been a major challenge in systems biology for decades. Many approaches have been proposed to solve this problem. However, there is still much room for the improvement of GRN inference. Integrating data from different sources is a promising strategy. Epigenetic modifications have a close relationship with gene regulation. Hence, epigenetic data such as histone modification profiles can provide useful information for uncovering regulatory interactions between genes. In this paper, we propose a method to integrate epigenetic data into the inference of GRNs. In particular, a dynamic Bayesian network (DBN) is employed to infer gene regulations from time-series gene expression data. Epigenetic data (histone modification profiles here) are integrated into the prior probability distribution of the Bayesian model. Our method has been validated on both synthetic and real datasets. Experimental results show that the integration of epigenetic data can significantly improve the performance of GRN inference. As more epigenetic datasets become available, our method would be useful for elucidating the gene regulatory mechanisms driving various cellular activities. The source code and testing datasets are available at https://github.com/Zheng-Lab/MetaGRN/tree/master/histonePrior.
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38
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Berry E, Cummins B, Nerem RR, Smith LM, Haase SB, Gedeon T. Using extremal events to characterize noisy time series. J Math Biol 2020; 80:1523-1557. [PMID: 32008103 DOI: 10.1007/s00285-020-01471-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 01/13/2020] [Indexed: 10/25/2022]
Abstract
Experimental time series provide an informative window into the underlying dynamical system, and the timing of the extrema of a time series (or its derivative) contains information about its structure. However, the time series often contain significant measurement errors. We describe a method for characterizing a time series for any assumed level of measurement error [Formula: see text] by a sequence of intervals, each of which is guaranteed to contain an extremum for any function that [Formula: see text]-approximates the time series. Based on the merge tree of a continuous function, we define a new object called the normalized branch decomposition, which allows us to compute intervals for any level [Formula: see text]. We show that there is a well-defined total order on these intervals for a single time series, and that it is naturally extended to a partial order across a collection of time series comprising a dataset. We use the order of the extracted intervals in two applications. First, the partial order describing a single dataset can be used to pattern match against switching model output (Cummins et al. in SIAM J Appl Dyn Syst 17(2):1589-1616, 2018), which allows the rejection of a network model. Second, the comparison between graph distances of the partial orders of different datasets can be used to quantify similarity between biological replicates.
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Affiliation(s)
- Eric Berry
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA
| | - Bree Cummins
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA.
| | - Robert R Nerem
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA
| | | | | | - Tomas Gedeon
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA
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39
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Zhang Y, Li QN, Xiang DX, Zhou K, Xu Q, Zhang CY. Development of a bidirectional isothermal amplification strategy for the sensitive detection of transcription factors in cancer cells. Chem Commun (Camb) 2020; 56:8952-8955. [DOI: 10.1039/d0cc03134h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We develop a bidirectional isothermal amplification strategy for the sensitive detection of transcription factors in cancer cells.
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Affiliation(s)
- Yan Zhang
- College of Chemistry
- Chemical Engineering and Materials Science
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong
- Key Laboratory of Molecular and Nano Probes
- Ministry of Education
| | - Qing-nan Li
- College of Chemistry
- Chemical Engineering and Materials Science
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong
- Key Laboratory of Molecular and Nano Probes
- Ministry of Education
| | - Dong-xue Xiang
- College of Chemistry
- Chemical Engineering and Materials Science
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong
- Key Laboratory of Molecular and Nano Probes
- Ministry of Education
| | - Kaiyue Zhou
- School of Food and Biological Engineering
- Shanxi University of Science and Technology
- Xi’an 710021
- P. R. China
| | - Qinfeng Xu
- School of Food and Biological Engineering
- Shanxi University of Science and Technology
- Xi’an 710021
- P. R. China
| | - Chun-yang Zhang
- College of Chemistry
- Chemical Engineering and Materials Science
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong
- Key Laboratory of Molecular and Nano Probes
- Ministry of Education
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40
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Rendsvig JKH, Workman CT, Hoof JB. Bidirectional histone-gene promoters in Aspergillus: characterization and application for multi-gene expression. Fungal Biol Biotechnol 2019; 6:24. [PMID: 31867115 PMCID: PMC6900853 DOI: 10.1186/s40694-019-0088-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 11/23/2019] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Filamentous fungi are important producers of enzymes and bioactive secondary metabolites and are exploited for industrial purposes. Expression and characterization of biosynthetic pathways requires stable expression of multiple genes in the production host. Fungal promoters are indispensable for the accomplishment of this task, and libraries of promoters that show functionality across diverse fungal species facilitate synthetic biology approaches, pathway expression, and cell-factory construction. RESULTS In this study, we characterized the intergenic region between the genes encoding histones H4.1 and H3, from five phylogenetically diverse species of Aspergillus, as bidirectional promoters (Ph4h3). By expression of the genes encoding fluorescent proteins mRFP1 and mCitrine, we show at the translational and transcriptional level that this region from diverse species is applicable as strong and constitutive bidirectional promoters in Aspergillus nidulans. Bioinformatic analysis showed that the divergent gene orientation of h4.1 and h3 appears maintained among fungi, and that the Ph4h3 display conserved DNA motifs among the investigated 85 Aspergilli. Two of the heterologous Ph4h3s were utilized for single-locus expression of four genes from the putative malformin producing pathway from Aspergillus brasiliensis in A. nidulans. Strikingly, heterologous expression of mlfA encoding the non-ribosomal peptide synthetase is sufficient for biosynthesis of malformins in A. nidulans, which indicates an iterative use of one adenylation domain in the enzyme. However, this resulted in highly stressed colonies, which was reverted to a healthy phenotype by co-expressing the residual four genes from the putative biosynthetic gene cluster. CONCLUSIONS Our study has documented that Ph4h3 is a strong constitutive bidirectional promoter and a valuable new addition to the genetic toolbox of at least the genus Aspergillus.
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Affiliation(s)
- Jakob K. H. Rendsvig
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Christopher T. Workman
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Jakob B. Hoof
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
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41
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Benz C, Urbaniak MD. Organising the cell cycle in the absence of transcriptional control: Dynamic phosphorylation co-ordinates the Trypanosoma brucei cell cycle post-transcriptionally. PLoS Pathog 2019; 15:e1008129. [PMID: 31830130 PMCID: PMC6907760 DOI: 10.1371/journal.ppat.1008129] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/07/2019] [Indexed: 11/18/2022] Open
Abstract
The cell division cycle of the unicellular eukaryote Trypanosome brucei is tightly regulated despite the paucity of transcriptional control that results from the arrangement of genes in polycistronic units and lack of dynamically regulated transcription factors. To identify the contribution of dynamic phosphorylation to T. brucei cell cycle control we have combined cell cycle synchronisation by centrifugal elutriation with quantitative phosphoproteomic analysis. Cell cycle regulated changes in phosphorylation site abundance (917 sites, average 5-fold change) were more widespread and of a larger magnitude than changes in protein abundance (443 proteins, average 2-fold change) and were mostly independent of each other. Hierarchical clustering of co-regulated phosphorylation sites according to their cell cycle profile revealed that a bulk increase in phosphorylation occurs across the cell cycle, with a significant enrichment of known cell cycle regulators and RNA binding proteins (RBPs) within the largest clusters. Cell cycle regulated changes in essential cell cycle kinases are temporally co-ordinated with differential phosphorylation of components of the kinetochore and eukaryotic initiation factors, along with many RBPs not previously linked to the cell cycle such as eight PSP1-C terminal domain containing proteins. The temporal profiles demonstrate the importance of dynamic phosphorylation in co-ordinating progression through the cell cycle, and provide evidence that RBPs play a central role in post-transcriptional regulation of the T. brucei cell cycle. Data are available via ProteomeXchange with identifier PXD013488.
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Affiliation(s)
- Corinna Benz
- Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom
| | - Michael D. Urbaniak
- Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom
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42
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Chen Z, Wang Z, Chang YCI. Sequential adaptive variables and subject selection for GEE methods. Biometrics 2019; 76:496-507. [PMID: 31598956 DOI: 10.1111/biom.13160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 10/02/2019] [Indexed: 11/30/2022]
Abstract
Modeling correlated or highly stratified multiple-response data is a common data analysis task in many applications, such as those in large epidemiological studies or multisite cohort studies. The generalized estimating equations method is a popular statistical method used to analyze these kinds of data, because it can manage many types of unmeasured dependence among outcomes. Collecting large amounts of highly stratified or correlated response data is time-consuming; thus, the use of a more aggressive sampling strategy that can accelerate this process-such as the active-learning methods found in the machine-learning literature-will always be beneficial. In this study, we integrate adaptive sampling and variable selection features into a sequential procedure for modeling correlated response data. Besides reporting the statistical properties of the proposed procedure, we also use both synthesized and real data sets to demonstrate the usefulness of our method.
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Affiliation(s)
- Zimu Chen
- International Institute of Finance, School of Management, University of Science and Technology of China, Hefei, China
| | - Zhanfeng Wang
- International Institute of Finance, School of Management, University of Science and Technology of China, Hefei, China
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Will T, Helms V. Differential analysis of combinatorial protein complexes with CompleXChange. BMC Bioinformatics 2019; 20:300. [PMID: 31159772 PMCID: PMC6547514 DOI: 10.1186/s12859-019-2852-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 04/26/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although a considerable number of proteins operate as multiprotein complexes and not on their own, organism-wide studies so far are only able to quantify individual proteins or protein-coding genes in a condition-specific manner for a sizeable number of samples, but not their assemblies. Consequently, there exist large amounts of transcriptomic data and an increasing amount of data on proteome abundance, but quantitative knowledge on complexomes is missing. This deficiency impedes the applicability of the powerful tool of differential analysis in the realm of macromolecular complexes. Here, we present a pipeline for differential analysis of protein complexes based on predicted or manually assigned complexes and inferred complex abundances, which can be easily applied on a whole-genome scale. RESULTS We observed for simulated data that results obtained by our complex abundance estimation algorithm were in better agreement with the ground truth and physicochemically more reasonable compared to previous efforts that used linear programming while running in a fraction of the time. The practical usability of the method was assessed in the context of transcription factor complexes in human monocyte and lymphoblastoid samples. We demonstrated that our new method is robust against false-positive detection and reports deregulated complexomes that can only be partially explained by differential analysis of individual protein-coding genes. Furthermore we showed that deregulated complexes identified by the tool potentially harbor significant yet unused information content. CONCLUSIONS CompleXChange allows to analyze deregulation of the protein complexome on a whole-genome scale by integrating a plethora of input data that is already available. A platform-independent Java binary, a user guide with example data and the source code are freely available at https://sourceforge.net/projects/complexchange/ .
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Affiliation(s)
- Thorsten Will
- Center for Bioinformatics, Saarland University, Campus E2.1, Saarbrücken, 66123, Germany.,Graduate School of Computer Science, Saarland University, Campus E1.3, Saarbrücken, 66123, Germany
| | - Volkhard Helms
- Center for Bioinformatics, Saarland University, Campus E2.1, Saarbrücken, 66123, Germany.
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Xie B, Becker E, Stuparevic I, Wery M, Szachnowski U, Morillon A, Primig M. The anti-cancer drug 5-fluorouracil affects cell cycle regulators and potential regulatory long non-coding RNAs in yeast. RNA Biol 2019; 16:727-741. [PMID: 30760080 PMCID: PMC6546400 DOI: 10.1080/15476286.2019.1581596] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/16/2019] [Accepted: 02/06/2019] [Indexed: 10/27/2022] Open
Abstract
5-fluorouracil (5-FU) was isolated as an inhibitor of thymidylate synthase, which is important for DNA synthesis. The drug was later found to also affect the conserved 3'-5' exoribonuclease EXOSC10/Rrp6, a catalytic subunit of the RNA exosome that degrades and processes protein-coding and non-coding transcripts. Work on 5-FU's cytotoxicity has been focused on mRNAs and non-coding transcripts such as rRNAs, tRNAs and snoRNAs. However, the effect of 5-FU on long non-coding RNAs (lncRNAs), which include regulatory transcripts important for cell growth and differentiation, is poorly understood. RNA profiling of synchronized 5-FU treated yeast cells and protein assays reveal that the drug specifically inhibits a set of cell cycle regulated genes involved in mitotic division, by decreasing levels of the paralogous Swi5 and Ace2 transcriptional activators. We also observe widespread accumulation of different lncRNA types in treated cells, which are typically present at high levels in a strain lacking EXOSC10/Rrp6. 5-FU responsive lncRNAs include potential regulatory antisense transcripts that form double-stranded RNAs (dsRNAs) with overlapping sense mRNAs. Some of these transcripts encode proteins important for cell growth and division, such as the transcription factor Ace2, and the RNA exosome subunit EXOSC6/Mtr3. In addition to revealing a transcriptional effect of 5-FU action via DNA binding regulators involved in cell cycle progression, our results have implications for the function of putative regulatory lncRNAs in 5-FU mediated cytotoxicity. The data raise the intriguing possibility that the drug deregulates lncRNAs/dsRNAs involved in controlling eukaryotic cell division, thereby highlighting a new class of promising therapeutical targets.
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Affiliation(s)
- Bingning Xie
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)- UMR_S 1085, Rennes, France
| | - Emmanuelle Becker
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)- UMR_S 1085, Rennes, France
- Univ Rennes, Inria, CNRS, IRISA F-35000, Rennes, France
| | - Igor Stuparevic
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)- UMR_S 1085, Rennes, France
| | - Maxime Wery
- ncRNA, Epigenetic and Genome Fluidity, Institut Curie, PSL UniversityCNRS UMR 3244, Université Pierre et Marie Curie, Paris, France
| | - Ugo Szachnowski
- ncRNA, Epigenetic and Genome Fluidity, Institut Curie, PSL UniversityCNRS UMR 3244, Université Pierre et Marie Curie, Paris, France
| | - Antonin Morillon
- ncRNA, Epigenetic and Genome Fluidity, Institut Curie, PSL UniversityCNRS UMR 3244, Université Pierre et Marie Curie, Paris, France
| | - Michael Primig
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)- UMR_S 1085, Rennes, France
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45
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Nonparametric independence screening for ultra-high dimensional generalized varying coefficient models with longitudinal data. J MULTIVARIATE ANAL 2019. [DOI: 10.1016/j.jmva.2018.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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46
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Liu W, Rajapakse JC. Fusing gene expressions and transitive protein-protein interactions for inference of gene regulatory networks. BMC SYSTEMS BIOLOGY 2019; 13:37. [PMID: 30953534 PMCID: PMC6449891 DOI: 10.1186/s12918-019-0695-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
BACKGROUND Systematic fusion of multiple data sources for Gene Regulatory Networks (GRN) inference remains a key challenge in systems biology. We incorporate information from protein-protein interaction networks (PPIN) into the process of GRN inference from gene expression (GE) data. However, existing PPIN remain sparse and transitive protein interactions can help predict missing protein interactions. We therefore propose a systematic probabilistic framework on fusing GE data and transitive protein interaction data to coherently build GRN. RESULTS We use a Gaussian Mixture Model (GMM) to soft-cluster GE data, allowing overlapping cluster memberships. Next, a heuristic method is proposed to extend sparse PPIN by incorporating transitive linkages. We then propose a novel way to score extended protein interactions by combining topological properties of PPIN and correlations of GE. Following this, GE data and extended PPIN are fused using a Gaussian Hidden Markov Model (GHMM) in order to identify gene regulatory pathways and refine interaction scores that are then used to constrain the GRN structure. We employ a Bayesian Gaussian Mixture (BGM) model to refine the GRN derived from GE data by using the structural priors derived from GHMM. Experiments on real yeast regulatory networks demonstrate both the feasibility of the extended PPIN in predicting transitive protein interactions and its effectiveness on improving the coverage and accuracy the proposed method of fusing PPIN and GE to build GRN. CONCLUSION The GE and PPIN fusion model outperforms both the state-of-the-art single data source models (CLR, GENIE3, TIGRESS) as well as existing fusion models under various constraints.
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Affiliation(s)
- Wenting Liu
- School of Public Health and Management, Hubei University of Medicine, Shiyan, Hubei China
- Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA USA
| | - Jagath C. Rajapakse
- School of Computer Engineering, Nanyang Technological University, Singapore, Singapore
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47
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Cho CY, Kelliher CM, Haase SB. The cell-cycle transcriptional network generates and transmits a pulse of transcription once each cell cycle. Cell Cycle 2019; 18:363-378. [PMID: 30668223 PMCID: PMC6422481 DOI: 10.1080/15384101.2019.1570655] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Multiple studies have suggested the critical roles of cyclin-dependent kinases (CDKs) as well as a transcription factor (TF) network in generating the robust cell-cycle transcriptional program. However, the precise mechanisms by which these components function together in the gene regulatory network remain unclear. Here we show that the TF network can generate and transmit a "pulse" of transcription independently of CDK oscillations. The premature firing of the transcriptional pulse is prevented by early G1 inhibitors, including transcriptional corepressors and the E3 ubiquitin ligase complex APCCdh1. We demonstrate that G1 cyclin-CDKs facilitate the activation and accumulation of TF proteins in S/G2/M phases through inhibiting G1 transcriptional corepressors (Whi5 and Stb1) and APCCdh1, thereby promoting the initiation and propagation of the pulse by the TF network. These findings suggest a unique oscillatory mechanism in which global phase-specific transcription emerges from a pulse-generating network that fires once-and-only-once at the start of the cycle.
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Affiliation(s)
- Chun-Yi Cho
- Department of Biology, Duke University, Durham, NC, USA
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48
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Averbukh I, Lai SL, Doe CQ, Barkai N. A repressor-decay timer for robust temporal patterning in embryonic Drosophila neuroblast lineages. eLife 2018; 7:38631. [PMID: 30526852 PMCID: PMC6303102 DOI: 10.7554/elife.38631] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 12/10/2018] [Indexed: 11/13/2022] Open
Abstract
Biological timers synchronize patterning processes during embryonic development. In the Drosophila embryo, neural progenitors (neuroblasts; NBs) produce a sequence of unique neurons whose identities depend on the sequential expression of temporal transcription factors (TTFs). The stereotypy and precision of NB lineages indicate reproducible TTF timer progression. We combine theory and experiments to define the timer mechanism. The TTF timer is commonly described as a relay of activators, but its regulatory circuit is also consistent with a repressor-decay timer, where TTF expression begins when its repressor decays. Theory shows that repressor-decay timers are more robust to parameter variations than activator-relay timers. This motivated us to experimentally compare the relative importance of the relay and decay interactions in vivo. Comparing WT and mutant NBs at high temporal resolution, we show that the TTF sequence progresses primarily by repressor-decay. We suggest that need for robust performance shapes the evolutionary-selected designs of biological circuits.
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Affiliation(s)
- Inna Averbukh
- Department of Molecular Genetics, Weizmann institute of science, Rehovot, Israel
| | - Sen-Lin Lai
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
| | - Chris Q Doe
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
| | - Naama Barkai
- Department of Molecular Genetics, Weizmann institute of science, Rehovot, Israel
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49
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Wang L, Li S, Sun Z, Wen G, Zheng F, Fu C, Li H. Segmentation of yeast cell's bright-field image with an edge-tracing algorithm. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-7. [PMID: 30456935 DOI: 10.1117/1.jbo.23.11.116503] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 10/17/2018] [Indexed: 06/09/2023]
Abstract
Phenotype analysis of yeast cell requires high-throughput imaging and automatic analysis of abundant image data. At first, each cell needs to be segmented and labeled in the bright-field images. However, the ambiguous boundary of bright-field yeast cell images leads to the failure of traditional segmentation algorithms. We propose a segmentation algorithm based on the morphological characteristics of yeast cells. Seed points are first identified along the cell contour and then connected by an edge tracing approach. In this way, "ill-detected" noise points are removed so that edges of yeast cells can be successfully extracted in bright-field images with sparsely distributed cells. In densely packed images, yeast cells with normal morphology can also be correctly segmented and labeled.
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Affiliation(s)
- Linbo Wang
- Chinese Academy of Sciences, Suzhou Institute of Biomedical Engineering and Technology, CAS Center f, China
| | - Simin Li
- Chinese Academy of Sciences, Suzhou Institute of Biomedical Engineering and Technology, CAS Center f, China
| | - Zhenglong Sun
- Chinese Academy of Sciences, Suzhou Institute of Biomedical Engineering and Technology, CAS Center f, China
| | - Gang Wen
- Chinese Academy of Sciences, Suzhou Institute of Biomedical Engineering and Technology, CAS Center f, China
| | - Fan Zheng
- University of Sciences and Technology of China, College of Life Sciences, Baohe District, Hefei, China
| | - Chuanhai Fu
- University of Sciences and Technology of China, College of Life Sciences, Baohe District, Hefei, China
| | - Hui Li
- Chinese Academy of Sciences, Suzhou Institute of Biomedical Engineering and Technology, CAS Center f, China
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50
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Kelliher CM, Foster MW, Motta FC, Deckard A, Soderblom EJ, Moseley MA, Haase SB. Layers of regulation of cell-cycle gene expression in the budding yeast Saccharomyces cerevisiae. Mol Biol Cell 2018; 29:2644-2655. [PMID: 30207828 PMCID: PMC6249835 DOI: 10.1091/mbc.e18-04-0255] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/30/2018] [Accepted: 09/04/2018] [Indexed: 11/11/2022] Open
Abstract
In the budding yeast Saccharomyces cerevisiae, transcription factors (TFs) regulate the periodic expression of many genes during the cell cycle, including gene products required for progression through cell-cycle events. Experimental evidence coupled with quantitative models suggests that a network of interconnected TFs is capable of regulating periodic genes over the cell cycle. Importantly, these dynamical models were built on transcriptomics data and assumed that TF protein levels and activity are directly correlated with mRNA abundance. To ask whether TF transcripts match protein expression levels as cells progress through the cell cycle, we applied a multiplexed targeted mass spectrometry approach (parallel reaction monitoring) to synchronized populations of cells. We found that protein expression of many TFs and cell-cycle regulators closely followed their respective mRNA transcript dynamics in cycling wild-type cells. Discordant mRNA/protein expression dynamics was also observed for a subset of cell-cycle TFs and for proteins targeted for degradation by E3 ubiquitin ligase complexes such as SCF (Skp1/Cul1/F-box) and APC/C (anaphase-promoting complex/cyclosome). We further profiled mutant cells lacking B-type cyclin/CDK activity ( clb1-6) where oscillations in ubiquitin ligase activity, cyclin/CDKs, and cell-cycle progression are halted. We found that a number of proteins were no longer periodically degraded in clb1-6 mutants compared with wild type, highlighting the importance of posttranscriptional regulation. Finally, the TF complexes responsible for activating G1/S transcription (SBF and MBF) were more constitutively expressed at the protein level than at periodic mRNA expression levels in both wild-type and mutant cells. This comprehensive investigation of cell-cycle regulators reveals that multiple layers of regulation (transcription, protein stability, and proteasome targeting) affect protein expression dynamics during the cell cycle.
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Affiliation(s)
| | - Matthew W. Foster
- Duke Center for Genomic and Computational Biology, Proteomics and Metabolomics Shared Resource, Durham, NC 27701
| | | | | | - Erik J. Soderblom
- Duke Center for Genomic and Computational Biology, Proteomics and Metabolomics Shared Resource, Durham, NC 27701
| | - M. Arthur Moseley
- Duke Center for Genomic and Computational Biology, Proteomics and Metabolomics Shared Resource, Durham, NC 27701
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