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Moon JM, Capra JA, Abbot P, Rokas A. Immune Regulation in Eutherian Pregnancy: Live Birth Coevolved with Novel Immune Genes and Gene Regulation. Bioessays 2019; 41:e1900072. [PMID: 31373044 DOI: 10.1002/bies.201900072] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/03/2019] [Indexed: 11/05/2022]
Abstract
Novel regulatory elements that enabled expression of pre-existing immune genes in reproductive tissues and novel immune genes with pregnancy-specific roles in eutherians have shaped the evolution of mammalian pregnancy by facilitating the emergence of novel mechanisms for immune regulation over its course. Trade-offs arising from conflicting fitness effects on reproduction and host defenses have further influenced the patterns of genetic variation of these genes. These three mechanisms (novel regulatory elements, novel immune genes, and trade-offs) played a pivotal role in refining the regulation of maternal immune systems during pregnancy in eutherians, likely facilitating the establishment of prolonged direct maternal-fetal contact in eutherians without causing immunological rejection of the genetically distinct fetus.
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Affiliation(s)
- Jiyun M Moon
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA
| | - John A Capra
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA.,Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, 37235, USA.,Department of Biomedical Informatics, Vanderbilt University, Nashville, TN, 37235, USA
| | - Patrick Abbot
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37235, USA.,Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, 37235, USA.,Department of Biomedical Informatics, Vanderbilt University, Nashville, TN, 37235, USA
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102
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Schuster J, Uzun A, Stablia J, Schorl C, Mori M, Padbury JF. Effect of prematurity on genome wide methylation in the placenta. BMC MEDICAL GENETICS 2019; 20:116. [PMID: 31253109 PMCID: PMC6599230 DOI: 10.1186/s12881-019-0835-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 05/24/2019] [Indexed: 12/12/2022]
Abstract
Background Preterm birth is a significant clinical problem and an enormous burden on society, affecting one in eight pregnant women and their newborns. Despite decades of research, the molecular mechanism underlying its pathogenesis remains unclear. Many studies have shown that preterm birth is associated with health risks across the later life course. The “fetal origins” hypothesis postulates that adverse intrauterine exposures are associated with later disease susceptibility. Our recent studies have focused on the placental epigenome at term. We extended these studies to genome-wide placental DNA methylation across a wide range of gestational ages. We applied methylation dependent immunoprecipitation/DNA sequencing (MeDIP-seq) to 9 placentas with gestational age from 25 weeks to term to identify differentially methylated regions (DMRs). Results Enrichment analysis revealed 427 DMRs with nominally significant differences in methylation between preterm and term placentas (p < 0.01) and 21 statistically significant DMRs after multiple comparison correction (FDR p < 0.05), of which 62% were hypo-methylated in preterm placentas vs term placentas. The majority of DMRs were in distal intergenic regions and introns. Significantly enriched pathways identified by Ingenuity Pathway Analysis (IPA) included Citrulline-Nitric Oxide Cycle and Fcy Receptor Mediated Phagocytosis in macrophages. The DMR gene set overlapped placental gene expression data, genes and pathways associated evolutionarily with preterm birth. Conclusion These studies form the basis for future studies on the epigenetics of preterm birth, “fetal programming” and the impact of environment exposures on this important clinical challenge. Electronic supplementary material The online version of this article (10.1186/s12881-019-0835-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jessica Schuster
- Pediatrics, Women & Infants Hospital, Providence, Rhode Island, 02905, USA
| | - Alper Uzun
- Pediatrics, Center for Computational Molecular Biology, Brown Medical School, Brown University, Providence, Rhode Island, 02906, USA
| | - Joan Stablia
- Pediatrics, Women & Infants Hospital, Providence, Rhode Island, 02905, USA
| | - Christoph Schorl
- Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island, 02906, USA
| | - Mari Mori
- Pediatrics and Genetics, Hasbro Children's Hospital, Providence, Rhode Island, 02905, USA
| | - James F Padbury
- Pediatrics, Center for Computational Molecular Biology, Brown Medical School, Brown University, Providence, Rhode Island, 02906, USA. .,, Providence, USA.
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103
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Onimaru K, Kuraku S. Inference of the ancestral vertebrate phenotype through vestiges of the whole-genome duplications. Brief Funct Genomics 2019; 17:352-361. [PMID: 29566222 PMCID: PMC6158797 DOI: 10.1093/bfgp/ely008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Inferring the phenotype of the last common ancestor of living vertebrates is a challenging problem because of several unresolvable factors. They include the lack of reliable out-groups of living vertebrates, poor information about less fossilizable organs and specialized traits of phylogenetically important species, such as lampreys and hagfishes (e.g. secondary loss of vertebrae in adult hagfishes). These factors undermine the reliability of ancestral reconstruction by traditional character mapping approaches based on maximum parsimony. In this article, we formulate an approach to hypothesizing ancestral vertebrate phenotypes using information from the phylogenetic and functional properties of genes duplicated by genome expansions in early vertebrate evolution. We named the conjecture as ‘chronological reconstruction of ohnolog functions (CHROF)’. This CHROF conjecture raises the possibility that the last common ancestor of living vertebrates may have had more complex traits than currently thought.
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Affiliation(s)
- Koh Onimaru
- RIKEN Center for Life Science Technologies, Kobe, Hyogo Japan.,Department of biological science, Tokyo Institute of Technology, Tokyo, Japan
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104
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Zhao W, Tan J, Zhu T, Ou J, Li Y, Shen L, Wu H, Han L, Liu Y, Jia X, Bai T, Li H, Ke X, Zhao J, Zou X, Hu Z, Guo H, Xia K. Rare inherited missense variants of POGZ associate with autism risk and disrupt neuronal development. J Genet Genomics 2019; 46:247-257. [PMID: 31196716 DOI: 10.1016/j.jgg.2019.04.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 03/22/2019] [Accepted: 04/02/2019] [Indexed: 11/16/2022]
Abstract
Excess de novo likely gene-disruptive and missense variants within dozens of genes have been identified in autism spectrum disorder (ASD) and other neurodevelopmental disorders. However, many rare inherited missense variants of these high-risk genes have not been thoroughly evaluated. In this study, we analyzed the rare missense variant burden of POGZ in a large cohort of ASD patients from the Autism Clinical and Genetic Resources in China (ACGC) and further dissected the functional effect of disease-associated missense variants on neuronal development. Our results showed a significant burden of rare missense variants in ASD patients compared to the control population (P = 4.6 × 10-5, OR = 3.96), and missense variants in ASD patients showed more severe predicted functional outcomes than those in controls. Furthermore, by leveraging published large-scale sequencing data of neurodevelopmental disorders (NDDs) and sporadic case reports, we identified 8 de novo missense variants of POGZ in NDD patients. Functional analysis revealed that two inherited, but not de novo, missense variants influenced the cellular localization of POGZ and failed to rescue the defects in neurite and dendritic spine development caused by Pogz knockdown in cultured mouse primary cortical neurons. Significantly, L1CAM, an autism candidate risk gene, is differentially expressed in POGZ deficient cell lines. Reduced expression of L1cam was able to partially rescue the neurite length defects caused by Pogz knockdown. Our study showed the important roles of rare inherited missense variants of POGZ in ASD risk and neuronal development and identified the potential downstream targets of POGZ, which are important for further molecular mechanism studies.
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Affiliation(s)
- Wenjing Zhao
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Jieqiong Tan
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Tengfei Zhu
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Jianjun Ou
- Mental Health Institute of the Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Ying Li
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Lu Shen
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Huidan Wu
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Lin Han
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Yanling Liu
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Xiangbin Jia
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Ting Bai
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Honghui Li
- Key Laboratory of Developmental Disorders in Children, Liuzhou Maternity and Child Healthcare Hospital, Liuzhou, 545001, China
| | - Xiaoyan Ke
- Child Mental Health Research Center, Nanjing Brain Hospital Affiliated of Nanjing Medical University, Nanjing, 210029, China
| | - Jingping Zhao
- Mental Health Institute of the Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Xiaobing Zou
- Children Development Behavior Center of the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Zhengmao Hu
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China
| | - Hui Guo
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China; Mental Health Institute of the Second Xiangya Hospital, Central South University, Changsha, 410011, China.
| | - Kun Xia
- Center of Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, 410078, China; School of Life Sciences and Technology, Xinjiang University, Ürümqi, 830046, China; CAS Center for Excellence in Brain Science and Intelligence Technology (CEBSIT), Chinese Academy of Sciences, Shanghai, 200030, China.
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105
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Todd CD, Deniz Ö, Taylor D, Branco MR. Functional evaluation of transposable elements as enhancers in mouse embryonic and trophoblast stem cells. eLife 2019; 8:e44344. [PMID: 31012843 PMCID: PMC6544436 DOI: 10.7554/elife.44344] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 04/20/2019] [Indexed: 12/18/2022] Open
Abstract
Transposable elements (TEs) are thought to have helped establish gene regulatory networks. Both the embryonic and extraembryonic lineages of the early mouse embryo have seemingly co-opted TEs as enhancers, but there is little evidence that they play significant roles in gene regulation. Here we tested a set of long terminal repeat TE families for roles as enhancers in mouse embryonic and trophoblast stem cells. Epigenomic and transcriptomic data suggested that a large number of TEs helped to establish tissue-specific gene expression programmes. Genetic editing of individual TEs confirmed a subset of these regulatory relationships. However, a wider survey via CRISPR interference of RLTR13D6 elements in embryonic stem cells revealed that only a minority play significant roles in gene regulation. Our results suggest that a subset of TEs are important for gene regulation in early mouse development, and highlight the importance of functional experiments when evaluating gene regulatory roles of TEs.
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Affiliation(s)
- Christopher D Todd
- Blizard Institute, Barts and The London School of Medicine and DentistryQueen Mary University of LondonLondonUnited Kingdom
- Centre for Genomic Health, Life Sciences InstituteQueen Mary University of LondonLondonUnited Kingdom
| | - Özgen Deniz
- Blizard Institute, Barts and The London School of Medicine and DentistryQueen Mary University of LondonLondonUnited Kingdom
- Centre for Genomic Health, Life Sciences InstituteQueen Mary University of LondonLondonUnited Kingdom
| | - Darren Taylor
- Centre for Genomic Health, Life Sciences InstituteQueen Mary University of LondonLondonUnited Kingdom
| | - Miguel R Branco
- Centre for Genomic Health, Life Sciences InstituteQueen Mary University of LondonLondonUnited Kingdom
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106
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Kellner M, Makałowski W. Transposable elements significantly contributed to the core promoters in the human genome. SCIENCE CHINA-LIFE SCIENCES 2019; 62:489-497. [DOI: 10.1007/s11427-018-9449-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 10/18/2018] [Indexed: 01/27/2023]
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107
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Halo JV, Pendleton AL, Jarosz AS, Gifford RJ, Day ML, Kidd JM. Origin and recent expansion of an endogenous gammaretroviral lineage in domestic and wild canids. Retrovirology 2019; 16:6. [PMID: 30845962 PMCID: PMC6407205 DOI: 10.1186/s12977-019-0468-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 02/28/2019] [Indexed: 01/20/2023] Open
Abstract
Background Vertebrate genomes contain a record of retroviruses that invaded the germlines of ancestral hosts and are passed to offspring as endogenous retroviruses (ERVs). ERVs can impact host function since they contain the necessary sequences for expression within the host. Dogs are an important system for the study of disease and evolution, yet no substantiated reports of infectious retroviruses in dogs exist. Here, we utilized Illumina whole genome sequence data to assess the origin and evolution of a recently active gammaretroviral lineage in domestic and wild canids. Results We identified numerous recently integrated loci of a canid-specific ERV-Fc sublineage within Canis, including 58 insertions that were absent from the reference assembly. Insertions were found throughout the dog genome including within and near gene models. By comparison of orthologous occupied sites, we characterized element prevalence across 332 genomes including all nine extant canid species, revealing evolutionary patterns of ERV-Fc segregation among species as well as subpopulations. Conclusions Sequence analysis revealed common disruptive mutations, suggesting a predominant form of ERV-Fc spread by trans complementation of defective proviruses. ERV-Fc activity included multiple circulating variants that infected canid ancestors from the last 20 million to within 1.6 million years, with recent bursts of germline invasion in the sublineage leading to wolves and dogs. Electronic supplementary material The online version of this article (10.1186/s12977-019-0468-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Julia V Halo
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA.
| | - Amanda L Pendleton
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Abigail S Jarosz
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA
| | - Robert J Gifford
- Centre for Virus Research, University of Glasgow, Glasgow, G12 8QQ, Scotland, UK
| | - Malika L Day
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA
| | - Jeffrey M Kidd
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.,Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, 100 Washtenaw Ave., Ann Arbor, MI, 48109, USA
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108
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Ellison C, Bachtrog D. Contingency in the convergent evolution of a regulatory network: Dosage compensation in Drosophila. PLoS Biol 2019; 17:e3000094. [PMID: 30742611 PMCID: PMC6417741 DOI: 10.1371/journal.pbio.3000094] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/14/2019] [Accepted: 01/18/2019] [Indexed: 11/18/2022] Open
Abstract
The repeatability or predictability of evolution is a central question in evolutionary biology and most often addressed in experimental evolution studies. Here, we infer how genetically heterogeneous natural systems acquire the same molecular changes to address how genomic background affects adaptation in natural populations. In particular, we take advantage of independently formed neo-sex chromosomes in Drosophila species that have evolved dosage compensation by co-opting the dosage-compensation male-specific lethal (MSL) complex to study the mutational paths that have led to the acquisition of hundreds of novel binding sites for the MSL complex in different species. This complex recognizes a conserved 21-bp GA-rich sequence motif that is enriched on the X chromosome, and newly formed X chromosomes recruit the MSL complex by de novo acquisition of this binding motif. We identify recently formed sex chromosomes in the D. melanica and D. robusta species groups by genome sequencing and generate genomic occupancy maps of the MSL complex to infer the location of novel binding sites. We find that diverse mutational paths were utilized in each species to evolve hundreds of de novo binding motifs along the neo-X, including expansions of microsatellites and transposable element (TE) insertions. However, the propensity to utilize a particular mutational path differs between independently formed X chromosomes and appears to be contingent on genomic properties of that species, such as simple repeat or TE density. This establishes the "genomic environment" as an important determinant in predicting the outcome of evolutionary adaptations.
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Affiliation(s)
- Christopher Ellison
- Department of Integrative Biology, University of California Berkeley, Berkeley, California, United States of America
| | - Doris Bachtrog
- Department of Integrative Biology, University of California Berkeley, Berkeley, California, United States of America
- * E-mail:
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109
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Carpentier MC, Manfroi E, Wei FJ, Wu HP, Lasserre E, Llauro C, Debladis E, Akakpo R, Hsing YI, Panaud O. Retrotranspositional landscape of Asian rice revealed by 3000 genomes. Nat Commun 2019; 10:24. [PMID: 30604755 PMCID: PMC6318337 DOI: 10.1038/s41467-018-07974-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 12/05/2018] [Indexed: 12/21/2022] Open
Abstract
The recent release of genomic sequences for 3000 rice varieties provides access to the genetic diversity at species level for this crop. We take advantage of this resource to unravel some features of the retrotranspositional landscape of rice. We develop software TRACKPOSON specifically for the detection of transposable elements insertion polymorphisms (TIPs) from large datasets. We apply this tool to 32 families of retrotransposons and identify more than 50,000 TIPs in the 3000 rice genomes. Most polymorphisms are found at very low frequency, suggesting that they may have occurred recently in agro. A genome-wide association study shows that these activations in rice may be triggered by external stimuli, rather than by the alteration of genetic factors involved in transposable element silencing pathways. Finally, the TIPs dataset is used to trace the origin of rice domestication. Our results suggest that rice originated from three distinct domestication events.
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Affiliation(s)
- Marie-Christine Carpentier
- Laboratoire Génome et Développement des Plantes, UMR CNRS/UPVD 5096, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy., 66860, Perpignan Cedex, France
| | - Ernandes Manfroi
- Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, 90040-060, Brazil
| | - Fu-Jin Wei
- Institute of Plant and Microbial Biology, Academia Sinica, 128, Section 2, Yien-chu-yuan Road, Nankang, 115, Taipei, Taiwan
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute, 1 Matsunosato, Tsukuba, 305-8687, Ibaraki, Japan
| | - Hshin-Ping Wu
- Institute of Plant and Microbial Biology, Academia Sinica, 128, Section 2, Yien-chu-yuan Road, Nankang, 115, Taipei, Taiwan
| | - Eric Lasserre
- Laboratoire Génome et Développement des Plantes, UMR CNRS/UPVD 5096, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy., 66860, Perpignan Cedex, France
| | - Christel Llauro
- Laboratoire Génome et Développement des Plantes, UMR CNRS/UPVD 5096, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy., 66860, Perpignan Cedex, France
| | - Emilie Debladis
- Laboratoire Génome et Développement des Plantes, UMR CNRS/UPVD 5096, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy., 66860, Perpignan Cedex, France
| | - Roland Akakpo
- Laboratoire Génome et Développement des Plantes, UMR CNRS/UPVD 5096, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy., 66860, Perpignan Cedex, France
| | - Yue-Ie Hsing
- Institute of Plant and Microbial Biology, Academia Sinica, 128, Section 2, Yien-chu-yuan Road, Nankang, 115, Taipei, Taiwan
| | - Olivier Panaud
- Laboratoire Génome et Développement des Plantes, UMR CNRS/UPVD 5096, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy., 66860, Perpignan Cedex, France.
- Institut Universitaire de France, 1 rue Descartes, 75231, Paris Cedex 05, France.
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110
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Abstract
Transposable elements (TEs) are low-complexity elements (e.g., LINEs, SINEs, SVAs, and HERVs) that make up to two-thirds of the human genome. There is mounting evidence that TEs play an essential role in molecular functions that influence genomic plasticity and gene expression regulation. With the advent of next-generation sequencing approaches, our understanding of the relationship between TEs and psychiatric disorders will greatly improve. In this chapter, the Authors comprehensively summarize the state-of the-art of TE research in animal models and humans supporting a framework in which TEs play a functional role in mechanisms affecting a variety of behaviors, including neurodevelopmental, neuropsychiatric, and neurodegenerative disorders. Finally, the Authors discuss recent therapeutic applications raised from the increasing experimental evidence on TE functional mechanisms.
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Affiliation(s)
- G Guffanti
- McLean Hospital - Harvard Medical School, Belmont, MA, USA.
| | - A Bartlett
- Department of Psychology, University of Massachusetts, Boston, Boston, MA, USA
| | - P DeCrescenzo
- McLean Hospital - Harvard Medical School, Belmont, MA, USA
| | - F Macciardi
- Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA, USA
| | - R Hunter
- Department of Psychology, University of Massachusetts, Boston, Boston, MA, USA
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111
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Zhang J, Simonti CN, Capra JA. Genome-wide maps of distal gene regulatory enhancers active in the human placenta. PLoS One 2018; 13:e0209611. [PMID: 30589856 PMCID: PMC6320013 DOI: 10.1371/journal.pone.0209611] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 12/03/2018] [Indexed: 12/30/2022] Open
Abstract
Placental dysfunction is implicated in many pregnancy complications, including preeclampsia and preterm birth (PTB). While both these syndromes are influenced by environmental risk factors, they also have a substantial genetic component that is not well understood. Precisely controlled gene expression during development is crucial to proper placental function and often mediated through gene regulatory enhancers. However, we lack accurate maps of placental enhancer activity due to the challenges of assaying the placenta and the difficulty of comprehensively identifying enhancers. To address the gap in our knowledge of gene regulatory elements in the placenta, we used a two-step machine learning pipeline to synthesize existing functional genomics studies, transcription factor (TF) binding patterns, and evolutionary information to predict placental enhancers. The trained classifiers accurately distinguish enhancers from the genomic background and placental enhancers from enhancers active in other tissues. Genomic features collected from tissues and cell lines involved in pregnancy are the most predictive of placental regulatory activity. Applying the classifiers genome-wide enabled us to create a map of 33,010 predicted placental enhancers, including 4,562 high-confidence enhancer predictions. The genome-wide placental enhancers are significantly enriched nearby genes associated with placental development and birth disorders and for SNPs associated with gestational age. These genome-wide predicted placental enhancers provide candidate regions for further testing in vitro, will assist in guiding future studies of genetic associations with pregnancy phenotypes, and aid interpretation of potential mechanisms of action for variants found through genetic studies.
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Affiliation(s)
- Joanna Zhang
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, United States of America
| | - Corinne N. Simonti
- Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, United States of America
| | - John A. Capra
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, United States of America
- Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, United States of America
- Department of Biomedical Informatics, Vanderbilt University, Nashville, TN, United States of America
- * E-mail:
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112
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Bourque G, Burns KH, Gehring M, Gorbunova V, Seluanov A, Hammell M, Imbeault M, Izsvák Z, Levin HL, Macfarlan TS, Mager DL, Feschotte C. Ten things you should know about transposable elements. Genome Biol 2018; 19:199. [PMID: 30454069 PMCID: PMC6240941 DOI: 10.1186/s13059-018-1577-z] [Citation(s) in RCA: 647] [Impact Index Per Article: 107.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Transposable elements (TEs) are major components of eukaryotic genomes. However, the extent of their impact on genome evolution, function, and disease remain a matter of intense interrogation. The rise of genomics and large-scale functional assays has shed new light on the multi-faceted activities of TEs and implies that they should no longer be marginalized. Here, we introduce the fundamental properties of TEs and their complex interactions with their cellular environment, which are crucial to understanding their impact and manifold consequences for organismal biology. While we draw examples primarily from mammalian systems, the core concepts outlined here are relevant to a broad range of organisms.
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Affiliation(s)
- Guillaume Bourque
- Department of Human Genetics, McGill University, Montréal, Québec, H3A 0G1, Canada.
- Canadian Center for Computational Genomics, McGill University, Montréal, Québec, H3A 0G1, Canada.
| | - Kathleen H Burns
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Mary Gehring
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA
| | - Vera Gorbunova
- Department of Biology, University of Rochester, Rochester, NY, 14627, USA
| | - Andrei Seluanov
- Department of Biology, University of Rochester, Rochester, NY, 14627, USA
| | - Molly Hammell
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Michaël Imbeault
- Department of Genetics, University of Cambridge, Cambridge, CB2 3EH, UK
| | - Zsuzsanna Izsvák
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125, Berlin, Germany
| | - Henry L Levin
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, The National Institutes of Health, Bethesda, Maryland, USA
| | - Todd S Macfarlan
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, The National Institutes of Health, Bethesda, Maryland, USA
| | - Dixie L Mager
- Terry Fox Laboratory, British Columbia Cancer Agency and Department of Medical Genetics, University of BC, Vancouver, BC, V5Z1L3, Canada
| | - Cédric Feschotte
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14850, USA.
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113
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Kelleher ES, Azevedo RBR, Zheng Y. The Evolution of Small-RNA-Mediated Silencing of an Invading Transposable Element. Genome Biol Evol 2018; 10:3038-3057. [PMID: 30252073 PMCID: PMC6404463 DOI: 10.1093/gbe/evy218] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2018] [Indexed: 12/11/2022] Open
Abstract
Transposable elements (TEs) are genomic parasites that impose fitness costs on their
hosts by producing deleterious mutations and disrupting gametogenesis. Host genomes avoid
these costs by regulating TE activity, particularly in germline cells where new insertions
are heritable and TEs are exceptionally active. However, the capacity of different
TE-associated fitness costs to select for repression in the host, and the role of
selection in the evolution of TE regulation more generally remain controversial. In this
study, we use forward, individual-based simulations to examine the evolution of
small-RNA-mediated TE regulation, a conserved mechanism for TE repression that is employed
by both prokaryotes and eukaryotes. To design and parameterize a biologically realistic
model, we drew on an extensive survey of empirical studies of the transposition and
regulation of P-element DNA transposons in Drosophila
melanogaster. We observed that even under conservative assumptions, where
small-RNA-mediated regulation reduces transposition only, repression evolves rapidly and
adaptively after the genome is invaded by a new TE in simulated populations. We further
show that the spread of repressor alleles through simulated populations is greatly
enhanced by two additional TE-imposed fitness costs: dysgenic sterility and ectopic
recombination. Finally, we demonstrate that the adaptive mutation rate to repression is a
critical parameter that influences both the evolutionary trajectory of host repression and
the associated proliferation of TEs after invasion in simulated populations. Our findings
suggest that adaptive evolution of TE regulation may be stronger and more prevalent than
previously appreciated, and provide a framework for interpreting empirical data.
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Affiliation(s)
- Erin S Kelleher
- Department of Biology and Biochemistry, University of Houston, Houston
| | | | - Yichen Zheng
- Department of Biology and Biochemistry, University of Houston, Houston.,Biodiversitt und Klima Forschungszentrum, Senckenberg Gesellschaft fr Naturforschung, Frankfurt am Main, Germany.,Institute of Genetics, University of Cologne, 50674 Cologne, NRW, Germany
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114
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Kelleher ES, Jaweria J, Akoma U, Ortega L, Tang W. QTL mapping of natural variation reveals that the developmental regulator bruno reduces tolerance to P-element transposition in the Drosophila female germline. PLoS Biol 2018; 16:e2006040. [PMID: 30376574 PMCID: PMC6207299 DOI: 10.1371/journal.pbio.2006040] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 09/26/2018] [Indexed: 12/15/2022] Open
Abstract
Transposable elements (TEs) are obligate genetic parasites that propagate in host genomes by replicating in germline nuclei, thereby ensuring transmission to offspring. This selfish replication not only produces deleterious mutations—in extreme cases, TE mobilization induces genotoxic stress that prohibits the production of viable gametes. Host genomes could reduce these fitness effects in two ways: resistance and tolerance. Resistance to TE propagation is enacted by germline-specific small-RNA-mediated silencing pathways, such as the Piwi-interacting RNA (piRNA) pathway, and is studied extensively. However, it remains entirely unknown whether host genomes may also evolve tolerance by desensitizing gametogenesis to the harmful effects of TEs. In part, the absence of research on tolerance reflects a lack of opportunity, as small-RNA-mediated silencing evolves rapidly after a new TE invades, thereby masking existing variation in tolerance. We have exploited the recent historical invasion of the Drosophila melanogaster genome by P-element DNA transposons in order to study tolerance of TE activity. In the absence of piRNA-mediated silencing, the genotoxic stress imposed by P-elements disrupts oogenesis and, in extreme cases, leads to atrophied ovaries that completely lack germline cells. By performing quantitative trait locus (QTL) mapping on a panel of recombinant inbred lines (RILs) that lack piRNA-mediated silencing of P-elements, we uncovered multiple QTL that are associated with differences in tolerance of oogenesis to P-element transposition. We localized the most significant QTL to a small 230-kb euchromatic region, with the logarithm of the odds (LOD) peak occurring in the bruno locus, which codes for a critical and well-studied developmental regulator of oogenesis. Genetic, cytological, and expression analyses suggest that bruno dosage modulates germline stem cell (GSC) loss in the presence of P-element activity. Our observations reveal segregating variation in TE tolerance for the first time, and implicate gametogenic regulators as a source of tolerant variants in natural populations. Transposable elements (TEs), or “jumping genes,” are mobile fragments of selfish DNA that leave deleterious mutations and DNA damage in their wake as they spread through host genomes. Their harmful effects are known to select for resistance by the host, in which the propagation of TEs is regulated and reduced. Here, we study for the first time whether host cells might also exhibit tolerance to TEs, by reducing their harmful effects without directly controlling their movement. By taking advantage of a panel of wild-type Drosophila melanogaster that lack resistance to P-element DNA transposons, we identified a small region of the genome that influences tolerance of P-element activity. We further demonstrate that a gene within that region, bruno, strongly influences the negative effects of P-element mobilization on the fly. When bruno dosage is reduced, the fertility of females carrying mobile P-elements is enhanced. The bruno locus encodes a protein with no known role in TE regulation but multiple well-characterized functions in oogenesis. We propose that bruno function reduces tolerance of the developing oocyte to DNA damage that is caused by P-elements.
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Affiliation(s)
- Erin S. Kelleher
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United State of America
- * E-mail:
| | - Jaweria Jaweria
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United State of America
| | - Uchechukwu Akoma
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United State of America
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Lily Ortega
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United State of America
| | - Wenpei Tang
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, United State of America
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115
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Huh I, Mendizabal I, Park T, Yi SV. Functional conservation of sequence determinants at rapidly evolving regulatory regions across mammals. PLoS Comput Biol 2018; 14:e1006451. [PMID: 30289877 PMCID: PMC6192654 DOI: 10.1371/journal.pcbi.1006451] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 10/17/2018] [Accepted: 08/20/2018] [Indexed: 01/08/2023] Open
Abstract
Recent advances in epigenomics have made it possible to map genome-wide regulatory regions using empirical methods. Subsequent comparative epigenomic studies have revealed that regulatory regions diverge rapidly between genome of different species, and that the divergence is more pronounced in enhancers than in promoters. To understand genomic changes underlying these patterns, we investigated if we can identify specific sequence fragments that are over-enriched in regulatory regions, thus potentially contributing to regulatory functions of such regions. Here we report numerous sequence fragments that are statistically over-enriched in enhancers and promoters of different mammals (which we refer to as ‘sequence determinants’). Interestingly, the degree of statistical enrichment, which presumably is associated with the degree of regulatory impacts of the specific sequence determinant, was significantly higher for promoter sequence determinants than enhancer sequence determinants. We further used a machine learning method to construct prediction models using sequence determinants. Remarkably, prediction models constructed from one species could be used to predict regulatory regions of other species with high accuracy. This observation indicates that even though the precise locations of regulatory regions diverge rapidly during evolution, the functional potential of sequence determinants underlying regulatory sequences may be conserved between species. Regions of the genome that do not encode genes but affect expression of other genes, such as enhancers and promoters, are referred to as regulatory regions. Because of their regulatory functions, it was thought that enhancers and promoters should be evolutionarily conserved. Regulatory regions can be now epigenomically identified because they are marked by specific modifications of histone tails at the chromatin level. Interestingly, when we compare epigenomically identified regulatory regions from different mammals, the specific positions of regulatory regions are often divergent between species. Enhancers in particular are highly divergent between species. In this study, we show that we can find sequence fragments that are statistically enriched in enhancers and promoters of different species, and that the degree of statistical enrichment can explain different levels of evolutionary sequence conservation between enhancers and promoters. We further constructed predictive models of enhancers and promoters using the enriched sequence fragments, and show that these models can not only accurately predict enhancers and promoters of the same species, but works comparably well when applied to other species. These results indicate that even though the specific positions of regulatory regions have diverged between species, the functions of sequence fragments that comprise those regions may be conserved.
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Affiliation(s)
- Iksoo Huh
- School of Biological Sciences, Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States of America
- College of Nursing, The Research Institute of Nursing Science, Seoul National University, Seoul, Korea
| | - Isabel Mendizabal
- School of Biological Sciences, Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States of America
| | - Taesung Park
- Department of Statistics, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Soojin V. Yi
- School of Biological Sciences, Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States of America
- * E-mail:
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116
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Sorrells TR, Johnson AN, Howard CJ, Britton CS, Fowler KR, Feigerle JT, Weil PA, Johnson AD. Intrinsic cooperativity potentiates parallel cis-regulatory evolution. eLife 2018; 7:37563. [PMID: 30198843 PMCID: PMC6173580 DOI: 10.7554/elife.37563] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 09/09/2018] [Indexed: 12/27/2022] Open
Abstract
Convergent evolutionary events in independent lineages provide an opportunity to understand why evolution favors certain outcomes over others. We studied such a case where a large set of genes-those coding for the ribosomal proteins-gained cis-regulatory sequences for a particular transcription regulator (Mcm1) in independent fungal lineages. We present evidence that these gains occurred because Mcm1 shares a mechanism of transcriptional activation with an ancestral regulator of the ribosomal protein genes, Rap1. Specifically, we show that Mcm1 and Rap1 have the inherent ability to cooperatively activate transcription through contacts with the general transcription factor TFIID. Because the two regulatory proteins share a common interaction partner, the presence of one ancestral cis-regulatory sequence can 'channel' random mutations into functional sites for the second regulator. At a genomic scale, this type of intrinsic cooperativity can account for a pattern of parallel evolution involving the fixation of hundreds of substitutions.
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Affiliation(s)
- Trevor R Sorrells
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Amanda N Johnson
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Conor J Howard
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Candace S Britton
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Kyle R Fowler
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
| | - Jordan T Feigerle
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - P Anthony Weil
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Alexander D Johnson
- Department of Biochemistry and Biophysics, Tetrad Graduate Program, University of California, San Francisco, United States.,Department of Microbiology and Immunology, University of California, San Francisco, United States
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117
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Guichard E, Peona V, Malagoli Tagliazucchi G, Abitante L, Jagoda E, Musella M, Ricci M, Rubio-Roldán A, Sarno S, Luiselli D, Pettener D, Taccioli C, Pagani L, Garcia-Perez JL, Boattini A. Impact of non-LTR retrotransposons in the differentiation and evolution of anatomically modern humans. Mob DNA 2018; 9:28. [PMID: 30147753 PMCID: PMC6094920 DOI: 10.1186/s13100-018-0133-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 08/07/2018] [Indexed: 12/31/2022] Open
Abstract
Background Transposable elements are biologically important components of eukaryote genomes. In particular, non-LTR retrotransposons (N-LTRrs) played a key role in shaping the human genome throughout evolution. In this study, we compared retrotransposon insertions differentially present in the genomes of Anatomically Modern Humans, Neanderthals, Denisovans and Chimpanzees, in order to assess the possible impact of retrotransposition in the differentiation of the human lineage. Results We first identified species-specific N-LTRrs and established their distribution in present day human populations. These analyses shortlisted a group of N-LTRr insertions that were found exclusively in Anatomically Modern Humans. These insertions are associated with an increase in the number of transcriptional/splicing variants of those genes they inserted in. The analysis of the functionality of genes containing human-specific N-LTRr insertions reflects changes that occurred during human evolution. In particular, the expression of genes containing the most recent N-LTRr insertions is enriched in the brain, especially in undifferentiated neurons, and these genes associate in networks related to neuron maturation and migration. Additionally, we identified candidate N-LTRr insertions that have likely produced new functional variants exclusive to modern humans, whose genomic loci show traces of positive selection. Conclusions Our results strongly suggest that N-LTRr impacted our differentiation as a species, most likely inducing an increase in neural complexity, and have been a constant source of genomic variability all throughout the evolution of the human lineage. Electronic supplementary material The online version of this article (10.1186/s13100-018-0133-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Etienne Guichard
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Valentina Peona
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy.,2Department of Evolutionary Biology (EBC), Uppsala University, SE-752 36 Uppsala, Sweden
| | | | - Lucia Abitante
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Evelyn Jagoda
- 4Human Evolutionary Biology, Harvard University, Cambridge, MA 02138 USA
| | - Margherita Musella
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Marco Ricci
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Alejandro Rubio-Roldán
- 5GENYO - Pfizer - Universidad de Granada - Junta de Andalucía Centre for Genomics and Oncological Research, PTS Granada, 18007 Granada, Spain
| | - Stefania Sarno
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Donata Luiselli
- 6Department of Cultural Heritage, University of Bologna, Ravenna Campus, 48121 Ravenna, Italy
| | - Davide Pettener
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Cristian Taccioli
- 7Department of Animal Medicine, Production and Health, University of Padova, 35020 Legnaro, Pd Italy
| | - Luca Pagani
- 8Department of Biology, University of Padova, 35131 Padova, Italy.,9Estonian Biocentre, Institute of Genomics, University of Tartu, 51010 Tartu, Estonia
| | - Jose Luis Garcia-Perez
- 5GENYO - Pfizer - Universidad de Granada - Junta de Andalucía Centre for Genomics and Oncological Research, PTS Granada, 18007 Granada, Spain.,MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine (IGMM), University of Edinburgh, Western General Hospital, Edinburgh, EH4 2XU UK
| | - Alessio Boattini
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
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118
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Than NG, Romero R, Tarca AL, Kekesi KA, Xu Y, Xu Z, Juhasz K, Bhatti G, Leavitt RJ, Gelencser Z, Palhalmi J, Chung TH, Gyorffy BA, Orosz L, Demeter A, Szecsi A, Hunyadi-Gulyas E, Darula Z, Simor A, Eder K, Szabo S, Topping V, El-Azzamy H, LaJeunesse C, Balogh A, Szalai G, Land S, Torok O, Dong Z, Kovalszky I, Falus A, Meiri H, Draghici S, Hassan SS, Chaiworapongsa T, Krispin M, Knöfler M, Erez O, Burton GJ, Kim CJ, Juhasz G, Papp Z. Integrated Systems Biology Approach Identifies Novel Maternal and Placental Pathways of Preeclampsia. Front Immunol 2018; 9:1661. [PMID: 30135684 PMCID: PMC6092567 DOI: 10.3389/fimmu.2018.01661] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 07/04/2018] [Indexed: 12/13/2022] Open
Abstract
Preeclampsia is a disease of the mother, fetus, and placenta, and the gaps in our understanding of the complex interactions among their respective disease pathways preclude successful treatment and prevention. The placenta has a key role in the pathogenesis of the terminal pathway characterized by exaggerated maternal systemic inflammation, generalized endothelial damage, hypertension, and proteinuria. This sine qua non of preeclampsia may be triggered by distinct underlying mechanisms that occur at early stages of pregnancy and induce different phenotypes. To gain insights into these molecular pathways, we employed a systems biology approach and integrated different "omics," clinical, placental, and functional data from patients with distinct phenotypes of preeclampsia. First trimester maternal blood proteomics uncovered an altered abundance of proteins of the renin-angiotensin and immune systems, complement, and coagulation cascades in patients with term or preterm preeclampsia. Moreover, first trimester maternal blood from preterm preeclamptic patients in vitro dysregulated trophoblastic gene expression. Placental transcriptomics of women with preterm preeclampsia identified distinct gene modules associated with maternal or fetal disease. Placental "virtual" liquid biopsy showed that the dysregulation of these disease gene modules originates during the first trimester. In vitro experiments on hub transcription factors of these gene modules demonstrated that DNA hypermethylation in the regulatory region of ZNF554 leads to gene down-regulation and impaired trophoblast invasion, while BCL6 and ARNT2 up-regulation sensitizes the trophoblast to ischemia, hallmarks of preterm preeclampsia. In summary, our data suggest that there are distinct maternal and placental disease pathways, and their interaction influences the clinical presentation of preeclampsia. The activation of maternal disease pathways can be detected in all phenotypes of preeclampsia earlier and upstream of placental dysfunction, not only downstream as described before, and distinct placental disease pathways are superimposed on these maternal pathways. This is a paradigm shift, which, in agreement with epidemiological studies, warrants for the central pathologic role of preexisting maternal diseases or perturbed maternal-fetal-placental immune interactions in preeclampsia. The description of these novel pathways in the "molecular phase" of preeclampsia and the identification of their hub molecules may enable timely molecular characterization of patients with distinct preeclampsia phenotypes.
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Affiliation(s)
- Nandor Gabor Than
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
- Maternity Private Department, Kutvolgyi Clinical Block, Semmelweis University, Budapest, Hungary
- First Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Roberto Romero
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, United States
- Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, MI, United States
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
| | - Adi Laurentiu Tarca
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Computer Science, College of Engineering, Wayne State University, Detroit, MI, United States
| | - Katalin Adrienna Kekesi
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Yi Xu
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Zhonghui Xu
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Channing Division of Network Medicine, Brigham and Women’s Hospital, Harvard University, Boston, MA, United States
| | - Kata Juhasz
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gaurav Bhatti
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | | | - Zsolt Gelencser
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Janos Palhalmi
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | | | - Balazs Andras Gyorffy
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Laszlo Orosz
- Department of Obstetrics and Gynaecology, University of Debrecen, Debrecen, Hungary
| | - Amanda Demeter
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Anett Szecsi
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Eva Hunyadi-Gulyas
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Zsuzsanna Darula
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Attila Simor
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Katalin Eder
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Szilvia Szabo
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
- Department of Morphology and Physiology, Semmelweis University, Budapest, Hungary
| | - Vanessa Topping
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Haidy El-Azzamy
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Christopher LaJeunesse
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Andrea Balogh
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gabor Szalai
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Systems Biology of Reproduction Lendulet Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Susan Land
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
| | - Olga Torok
- Department of Obstetrics and Gynaecology, University of Debrecen, Debrecen, Hungary
| | - Zhong Dong
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
| | - Ilona Kovalszky
- First Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
| | - Andras Falus
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | | | - Sorin Draghici
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
- Department of Clinical and Translational Science, Wayne State University, Detroit, MI, United States
| | - Sonia S. Hassan
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Tinnakorn Chaiworapongsa
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
| | | | - Martin Knöfler
- Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | - Offer Erez
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Obstetrics and Gynecology, Soroka University Medical Center School of Medicine, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Graham J. Burton
- Centre for Trophoblast Research, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Chong Jai Kim
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, United States
- Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Detroit, MI, United States
- Department of Pathology, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Pathology, Asan Medical Center, University of Ulsan, Seoul, South Korea
| | - Gabor Juhasz
- Laboratory of Proteomics, Department of Physiology and Neurobiology, ELTE Eotvos Lorand University, Budapest, Hungary
| | - Zoltan Papp
- Maternity Private Department, Kutvolgyi Clinical Block, Semmelweis University, Budapest, Hungary
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119
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Erkenbrack EM, Maziarz JD, Griffith OW, Liang C, Chavan AR, Nnamani MC, Wagner GP. The mammalian decidual cell evolved from a cellular stress response. PLoS Biol 2018; 16:e2005594. [PMID: 30142145 PMCID: PMC6108454 DOI: 10.1371/journal.pbio.2005594] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 06/29/2018] [Indexed: 11/19/2022] Open
Abstract
Among animal species, cell types vary greatly in terms of number and kind. The number of cell types found within an organism differs considerably between species, and cell type diversity is a significant contributor to differences in organismal structure and function. These observations suggest that cell type origination is a significant source of evolutionary novelty. The molecular mechanisms that result in the evolution of novel cell types, however, are poorly understood. Here, we show that a novel cell type of eutherians mammals, the decidual stromal cell (DSC), evolved by rewiring an ancestral cellular stress response. We isolated the precursor cell type of DSCs, endometrial stromal fibroblasts (ESFs), from the opossum Monodelphis domestica. We show that, in opossum ESFs, the majority of decidual core regulatory genes respond to decidualizing signals but do not regulate decidual effector genes. Rather, in opossum ESFs, decidual transcription factors function in apoptotic and oxidative stress response. We propose that rewiring of cellular stress responses was an important mechanism for the evolution of the eutherian decidual cell type.
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Affiliation(s)
- Eric M. Erkenbrack
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
| | - Jamie D. Maziarz
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
| | - Oliver W. Griffith
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
- School of Biosciences, University of Melbourne, Melbourne, Australia
| | - Cong Liang
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
- Interdepartmental Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, United States of America
| | - Arun R. Chavan
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
| | - Mauris C. Nnamani
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
| | - Günter P. Wagner
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Systems Biology Institute, Yale University, West Haven, Connecticut, United States of America
- Department of Obstetrics, Gynecology, and Reproductive Science, Yale University Medical School, New Haven, Connecticut, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, United States of America
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120
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Ivancevic AM, Kortschak RD, Bertozzi T, Adelson DL. Horizontal transfer of BovB and L1 retrotransposons in eukaryotes. Genome Biol 2018; 19:85. [PMID: 29983116 PMCID: PMC6036668 DOI: 10.1186/s13059-018-1456-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 05/23/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Transposable elements (TEs) are mobile DNA sequences, colloquially known as jumping genes because of their ability to replicate to new genomic locations. TEs can jump between organisms or species when given a vector of transfer, such as a tick or virus, in a process known as horizontal transfer. Here, we propose that LINE-1 (L1) and Bovine-B (BovB), the two most abundant TE families in mammals, were initially introduced as foreign DNA via ancient horizontal transfer events. RESULTS Using analyses of 759 plant, fungal and animal genomes, we identify multiple possible L1 horizontal transfer events in eukaryotic species, primarily involving Tx-like L1s in marine eukaryotes. We also extend the BovB paradigm by increasing the number of estimated transfer events compared to previous studies, finding new parasite vectors of transfer such as bed bug, leech and locust, and BovB occurrences in new lineages such as bat and frog. Given that these transposable elements have colonised more than half of the genome sequence in today's mammals, our results support a role for horizontal transfer in causing long-term genomic change in new host organisms. CONCLUSIONS We describe extensive horizontal transfer of BovB retrotransposons and provide the first evidence that L1 elements can also undergo horizontal transfer. With the advancement of genome sequencing technologies and bioinformatics tools, we anticipate our study to be a valuable resource for inferring horizontal transfer from large-scale genomic data.
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Affiliation(s)
- Atma M Ivancevic
- Department of Genetics and Evolution, Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
- Neurogenetics Research Program, Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - R Daniel Kortschak
- Department of Genetics and Evolution, Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Terry Bertozzi
- Department of Genetics and Evolution, Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
- Evolutionary Biology Unit, South Australian Museum, Adelaide, SA, Australia
| | - David L Adelson
- Department of Genetics and Evolution, Biological Sciences, The University of Adelaide, Adelaide, SA, Australia.
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121
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Jue NK, Foley RJ, Reznick DN, O'Neill RJ, O'Neill MJ. Tissue-Specific Transcriptome for Poeciliopsis prolifica Reveals Evidence for Genetic Adaptation Related to the Evolution of a Placental Fish. G3 (BETHESDA, MD.) 2018; 8:2181-2192. [PMID: 29720394 PMCID: PMC6027864 DOI: 10.1534/g3.118.200270] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 04/11/2018] [Indexed: 11/18/2022]
Abstract
The evolution of the placenta is an excellent model to examine the evolutionary processes underlying adaptive complexity due to the recent, independent derivation of placentation in divergent animal lineages. In fishes, the family Poeciliidae offers the opportunity to study placental evolution with respect to variation in degree of post-fertilization maternal provisioning among closely related sister species. In this study, we present a detailed examination of a new reference transcriptome sequence for the live-bearing, matrotrophic fish, Poeciliopsis prolifica, from multiple-tissue RNA-seq data. We describe the genetic components active in liver, brain, late-stage embryo, and the maternal placental/ovarian complex, as well as associated patterns of positive selection in a suite of orthologous genes found in fishes. Results indicate the expression of many signaling transcripts, "non-coding" sequences and repetitive elements in the maternal placental/ovarian complex. Moreover, patterns of positive selection in protein sequence evolution were found associated with live-bearing fishes, generally, and the placental P. prolifica, specifically, that appear independent of the general live-bearer lifestyle. Much of the observed patterns of gene expression and positive selection are congruent with the evolution of placentation in fish functionally converging with mammalian placental evolution and with the patterns of rapid evolution facilitated by the teleost-specific whole genome duplication event.
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Affiliation(s)
- Nathaniel K Jue
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
| | - Robert J Foley
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
| | - David N Reznick
- Department of Biology, University of California, Riverside, CA 92521
| | - Rachel J O'Neill
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
| | - Michael J O'Neill
- Institute for Systems Genomics and Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
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122
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Trizzino M, Kapusta A, Brown CD. Transposable elements generate regulatory novelty in a tissue-specific fashion. BMC Genomics 2018; 19:468. [PMID: 29914366 PMCID: PMC6006921 DOI: 10.1186/s12864-018-4850-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 06/01/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Transposable elements (TE) are an important source of evolutionary novelty in gene regulation. However, the mechanisms by which TEs contribute to gene expression are largely uncharacterized. RESULTS Here, we leverage Roadmap and GTEx data to investigate the association of TEs with active and repressed chromatin in 24 tissues. We find 112 human TE families enriched in active regions of the genome across tissues. Short Interspersed Nuclear Elements (SINEs) and DNA transposons are the most frequently enriched classes, while Long Terminal Repeat Retrotransposons (LTRs) are often enriched in a tissue-specific manner. We report across-tissue variability in TE enrichment in active regions. Genes with consistent expression across tissues are less likely to be associated with TE insertions. TE presence in repressed regions similarly follows tissue-specific patterns. Moreover, different TE classes correlate with different repressive marks: LTRs and Long Interspersed Nuclear Elements (LINEs) are overrepresented in regions marked by H3K9me3, while the other TEs are more likely to overlap regions with H3K27me3. Young TEs are typically enriched in repressed regions and depleted in active regions. We detect multiple instances of TEs that are enriched in tissue-specific active regulatory regions. Such TEs contain binding sites for transcription factors that are master regulators for the given tissue. These TEs are enriched in intronic enhancers, and their tissue-specific enrichment correlates with tissue-specific variations in the expression of the nearest genes. CONCLUSIONS We provide an integrated overview of the contribution of TEs to human gene regulation. Expanding previous analyses, we demonstrate that TEs can potentially contribute to the turnover of regulatory sequences in a tissue-specific fashion.
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Affiliation(s)
- Marco Trizzino
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, PA, USA. .,Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA.
| | - Aurélie Kapusta
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA.,USTAR, Center for Genetic Discovery, Salt Lake City, UT, USA
| | - Christopher D Brown
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA. .,Institute for Biomedical Informatics, University of Pennsylvania, Philadelphia, PA, USA.
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123
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Zeng L, Pederson SM, Cao D, Qu Z, Hu Z, Adelson DL, Wei C. Genome-Wide Analysis of the Association of Transposable Elements with Gene Regulation Suggests that Alu Elements Have the Largest Overall Regulatory Impact. J Comput Biol 2018; 25:551-562. [DOI: 10.1089/cmb.2017.0228] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Lu Zeng
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Stephen M. Pederson
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Danfeng Cao
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Zhipeng Qu
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Zhiqiang Hu
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - David L. Adelson
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Chaochun Wei
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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124
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Costanzo V, Bardelli A, Siena S, Abrignani S. Exploring the links between cancer and placenta development. Open Biol 2018; 8:180081. [PMID: 29950452 PMCID: PMC6030113 DOI: 10.1098/rsob.180081] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 06/05/2018] [Indexed: 12/19/2022] Open
Abstract
The development of metastatic cancer is a multistage process, which often requires decades to complete. Impairments in DNA damage control and DNA repair in cancer cell precursors generate genetically heterogeneous cell populations. However, despite heterogeneity most solid cancers have stereotypical behaviours, including invasiveness and suppression of immune responses that can be unleashed with immunotherapy targeting lymphocyte checkpoints. The mechanisms leading to the acquisition of stereotypical properties remain poorly understood. Reactivation of embryonic development processes in cells with unstable genomes might contribute to tumour expansion and metastasis formation. However, it is unclear whether these events are linked to immune response modulation. Tumours and embryos have non-self-components and need to avoid immune responses in their microenvironment. In mammalian embryos, neo-antigens are of paternal origin, while in tumour cells DNA mismatch repair and replication defects generate them. Inactivation of the maternal immune response towards the embryo, which occurs at the placental-maternal interface, is key to ensuring embryonic development. This regulation is accomplished by the trophoblast, which mimics several malignant cell features, including the ability to invade normal tissues and to avoid host immune responses, often adopting the same cancer immunoediting strategies. A better understanding as to whether and how genotoxic stress promotes cancer development through reactivation of programmes occurring during early stages of mammalian placentation could help to clarify resistance to drugs targeting immune checkpoint and DNA damage responses and to develop new therapeutic strategies to eradicate cancer.
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Affiliation(s)
- Vincenzo Costanzo
- IFOM, The FIRC Institute of Molecular Oncology, University of Milan Medical School, Milan, Italy
- Department of Oncology, University of Milan Medical School, Milan, Italy
| | - Alberto Bardelli
- Candiolo Cancer Institute-FPO, IRCCS, University of Turin, Candiolo, Turin, Italy
- Department of Oncology, University of Turin, Candiolo, Turin, Italy
| | - Salvatore Siena
- Department of Oncology, University of Milan Medical School, Milan, Italy
- Niguarda Cancer Center, Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Sergio Abrignani
- INGM, Istituto Nazionale Genetica Molecolare "Romeo ed Enrica Invernizzi", Milan, Italy
- University of Milan Medical School, Milan, Italy
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125
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Ricci M, Peona V, Guichard E, Taccioli C, Boattini A. Transposable Elements Activity is Positively Related to Rate of Speciation in Mammals. J Mol Evol 2018; 86:303-310. [PMID: 29855654 PMCID: PMC6028844 DOI: 10.1007/s00239-018-9847-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 05/24/2018] [Indexed: 02/05/2023]
Abstract
Transposable elements (TEs) play an essential role in shaping eukaryotic genomes and generating variability. Speciation and TE activity bursts could be strongly related in mammals, in which simple gradualistic models of differentiation do not account for the currently observed species variability. In order to test this hypothesis, we designed two parameters: the Density of insertion (DI) and the Relative rate of speciation (RRS). DI is the ratio between the number of TE insertions in a genome and its size, whereas the RRS is a conditional parameter designed to identify potential speciation bursts. Thus, by analyzing TE insertions in mammals, we defined the genomes as “hot” (high DI) and “cold” (low DI). Then, comparing TE activity among 29 taxonomical families of the whole Mammalia class, 16 intra-order pairs of mammalian species, and four superorders of Eutheria, we showed that taxa with high rates of speciation are associated with “hot” genomes, whereas taxa with low ones are associated with “cold” genomes. These results suggest a remarkable correlation between TE activity and speciation, also being consistent with patterns describing variable rates of differentiation and accounting for the different time frames of the speciation bursts.
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Affiliation(s)
- Marco Ricci
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy.
| | - Valentina Peona
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
- Department of Ecology and Genetics, University of Uppsala, Uppsala, Sweden
| | - Etienne Guichard
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy.
| | - Cristian Taccioli
- Department of Animal Medicine, Health and Production, University of Padova, Padova, Italy
| | - Alessio Boattini
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
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126
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Horns F, Petit E, Hood ME. Massive Expansion of Gypsy-Like Retrotransposons in Microbotryum Fungi. Genome Biol Evol 2018; 9:363-371. [PMID: 28164239 PMCID: PMC5381629 DOI: 10.1093/gbe/evx011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2017] [Indexed: 12/11/2022] Open
Abstract
Transposable elements (TEs) are selfish, autonomously replicating DNA sequences that constitute a major component of eukaryotic genomes and contribute to genome evolution through their movement and amplification. Many fungal genomes, including the anther-smut fungi in the basidiomycete genus Microbotryum, have genome defense mechanisms, such as repeat-induced point mutation (RIP), which hypermutate repetitive DNA and limit TE activity. Little is known about how hypermutation affects the tempo of TE activity and their sequence evolution. Here we report the identification of a massive burst-like expansion of Gypsy-like retrotransposons in a strain of Microbotryum. This TE expansion evidently occurred in the face of RIP-like hypermutation activity. By examining the fitness of individual TE insertion variants, we found that RIP-like mutations impair TE fitness and limit proliferation. Our results provide evidence for a punctuated pattern of TE expansion in a fungal genome, similar to that observed in animals and plants. While targeted hypermutation is often thought of as an effective protection against mobile element activity, our findings suggest that active TEs can persist and undergo selection while they proliferate in genomes that have RIP-like defenses.
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Affiliation(s)
- Felix Horns
- Department of Biology, Amherst College, Amherst, MA
| | - Elsa Petit
- Department of Biology, Amherst College, Amherst, MA
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127
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Ward MC, Zhao S, Luo K, Pavlovic BJ, Karimi MM, Stephens M, Gilad Y. Silencing of transposable elements may not be a major driver of regulatory evolution in primate iPSCs. eLife 2018; 7:33084. [PMID: 29648536 PMCID: PMC5943035 DOI: 10.7554/elife.33084] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Accepted: 04/11/2018] [Indexed: 12/16/2022] Open
Abstract
Transposable elements (TEs) comprise almost half of primate genomes and their aberrant regulation can result in deleterious effects. In pluripotent stem cells, rapidly evolving KRAB-ZNF genes target TEs for silencing by H3K9me3. To investigate the evolution of TE silencing, we performed H3K9me3 ChIP-seq experiments in induced pluripotent stem cells from 10 human and 7 chimpanzee individuals. We identified four million orthologous TEs and found the SVA and ERV families to be marked most frequently by H3K9me3. We found little evidence of inter-species differences in TE silencing, with as many as 82% of putatively silenced TEs marked at similar levels in humans and chimpanzees. TEs that are preferentially silenced in one species are a similar age to those silenced in both species and are not more likely to be associated with expression divergence of nearby orthologous genes. Our data suggest limited species-specificity of TE silencing across 6 million years of primate evolution.
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Affiliation(s)
- Michelle C Ward
- Department of Human Genetics, University of Chicago, Chicago, United States.,Department of Medicine, University of Chicago, Chicago, United States
| | - Siming Zhao
- Department of Human Genetics, University of Chicago, Chicago, United States
| | - Kaixuan Luo
- Department of Human Genetics, University of Chicago, Chicago, United States
| | - Bryan J Pavlovic
- Department of Human Genetics, University of Chicago, Chicago, United States
| | - Mohammad M Karimi
- MRC London Institute of Medical Sciences, Imperial College, London, United Kingdom
| | - Matthew Stephens
- Department of Human Genetics, University of Chicago, Chicago, United States.,Department of Statistics, University of Chicago, Chicago, United States
| | - Yoav Gilad
- Department of Human Genetics, University of Chicago, Chicago, United States.,Department of Medicine, University of Chicago, Chicago, United States
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128
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Thybert D, Roller M, Navarro FCP, Fiddes I, Streeter I, Feig C, Martin-Galvez D, Kolmogorov M, Janoušek V, Akanni W, Aken B, Aldridge S, Chakrapani V, Chow W, Clarke L, Cummins C, Doran A, Dunn M, Goodstadt L, Howe K, Howell M, Josselin AA, Karn RC, Laukaitis CM, Jingtao L, Martin F, Muffato M, Nachtweide S, Quail MA, Sisu C, Stanke M, Stefflova K, Van Oosterhout C, Veyrunes F, Ward B, Yang F, Yazdanifar G, Zadissa A, Adams DJ, Brazma A, Gerstein M, Paten B, Pham S, Keane TM, Odom DT, Flicek P. Repeat associated mechanisms of genome evolution and function revealed by the Mus caroli and Mus pahari genomes. Genome Res 2018; 28:448-459. [PMID: 29563166 PMCID: PMC5880236 DOI: 10.1101/gr.234096.117] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/05/2018] [Indexed: 12/31/2022]
Abstract
Understanding the mechanisms driving lineage-specific evolution in both primates and rodents has been hindered by the lack of sister clades with a similar phylogenetic structure having high-quality genome assemblies. Here, we have created chromosome-level assemblies of the Mus caroli and Mus pahari genomes. Together with the Mus musculus and Rattus norvegicus genomes, this set of rodent genomes is similar in divergence times to the Hominidae (human-chimpanzee-gorilla-orangutan). By comparing the evolutionary dynamics between the Muridae and Hominidae, we identified punctate events of chromosome reshuffling that shaped the ancestral karyotype of Mus musculus and Mus caroli between 3 and 6 million yr ago, but that are absent in the Hominidae. Hominidae show between four- and sevenfold lower rates of nucleotide change and feature turnover in both neutral and functional sequences, suggesting an underlying coherence to the Muridae acceleration. Our system of matched, high-quality genome assemblies revealed how specific classes of repeats can play lineage-specific roles in related species. Recent LINE activity has remodeled protein-coding loci to a greater extent across the Muridae than the Hominidae, with functional consequences at the species level such as reproductive isolation. Furthermore, we charted a Muridae-specific retrotransposon expansion at unprecedented resolution, revealing how a single nucleotide mutation transformed a specific SINE element into an active CTCF binding site carrier specifically in Mus caroli, which resulted in thousands of novel, species-specific CTCF binding sites. Our results show that the comparison of matched phylogenetic sets of genomes will be an increasingly powerful strategy for understanding mammalian biology.
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Affiliation(s)
- David Thybert
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
- Earlham Institute, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Maša Roller
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Fábio C P Navarro
- Yale University Medical School, Computational Biology and Bioinformatics Program, New Haven, Connecticut 06520, USA
| | - Ian Fiddes
- Department of Biomolecular Engineering, University of California, Santa Cruz, California 95064, USA
| | - Ian Streeter
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Christine Feig
- University of Cambridge, Cancer Research UK Cambridge Institute, Robinson Way, Cambridge CB2 0RE, United Kingdom
| | - David Martin-Galvez
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Mikhail Kolmogorov
- Department of Computer Science and Engineering, University of California, San Diego, La Jolla, California 92092, USA
| | - Václav Janoušek
- Department of Zoology, Faculty of Science, Charles University in Prague, 128 44 Prague, Czech Republic
| | - Wasiu Akanni
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Bronwen Aken
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Sarah Aldridge
- University of Cambridge, Cancer Research UK Cambridge Institute, Robinson Way, Cambridge CB2 0RE, United Kingdom
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Varshith Chakrapani
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - William Chow
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Laura Clarke
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Carla Cummins
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Anthony Doran
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Matthew Dunn
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Leo Goodstadt
- Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Kerstin Howe
- Yale University Medical School, Computational Biology and Bioinformatics Program, New Haven, Connecticut 06520, USA
| | - Matthew Howell
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Ambre-Aurore Josselin
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Robert C Karn
- Department of Medicine, College of Medicine, University of Arizona, Tuscon, Arizona 85724, USA
| | - Christina M Laukaitis
- Department of Medicine, College of Medicine, University of Arizona, Tuscon, Arizona 85724, USA
| | - Lilue Jingtao
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Fergal Martin
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Matthieu Muffato
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Stefanie Nachtweide
- Institute of Mathematics and Computer Science, University of Greifswald, Greifswald 17487, Germany
| | - Michael A Quail
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Cristina Sisu
- Yale University Medical School, Computational Biology and Bioinformatics Program, New Haven, Connecticut 06520, USA
| | - Mario Stanke
- Institute of Mathematics and Computer Science, University of Greifswald, Greifswald 17487, Germany
| | - Klara Stefflova
- University of Cambridge, Cancer Research UK Cambridge Institute, Robinson Way, Cambridge CB2 0RE, United Kingdom
| | - Cock Van Oosterhout
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Frederic Veyrunes
- Institut des Sciences de l'Evolution de Montpellier, Université Montpellier/CNRS, 34095 Montpellier, France
| | - Ben Ward
- Earlham Institute, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Fengtang Yang
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Golbahar Yazdanifar
- Department of Medicine, College of Medicine, University of Arizona, Tuscon, Arizona 85724, USA
| | - Amonida Zadissa
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - David J Adams
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Alvis Brazma
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
| | - Mark Gerstein
- Yale University Medical School, Computational Biology and Bioinformatics Program, New Haven, Connecticut 06520, USA
| | - Benedict Paten
- Department of Biomolecular Engineering, University of California, Santa Cruz, California 95064, USA
| | - Son Pham
- Bioturing Inc, San Diego, California 92121, USA
| | - Thomas M Keane
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Duncan T Odom
- University of Cambridge, Cancer Research UK Cambridge Institute, Robinson Way, Cambridge CB2 0RE, United Kingdom
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Paul Flicek
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, United Kingdom
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
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129
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Liu JL, Zhang WQ, Zhao M, Huang MY. Integration of Transcriptomic and Metabolomic Data Reveals Enhanced Steroid Hormone Biosynthesis in Mouse Uterus During Decidualization. Proteomics 2018; 17. [PMID: 28857456 DOI: 10.1002/pmic.201700059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 08/11/2017] [Indexed: 01/16/2023]
Abstract
It has been long recognized that decidualization is accompanied by significant changes in metabolic pathways. In the present study, we used the GC-TOF-MS approach to investigate the global metabolite profile changes associated with decidualization of mouse uterus on day 8 of pregnancy. We identified a total of 20 differentially accumulated metabolites, of which nine metabolites were down-regulated and 11 metabolites were up-regulated. As expected, seven differentially accumulated metabolites were involved in carbohydrate metabolism. We observed statistically significant changes in polyamines, putrescine and spermidine. Interestingly, the pantothenic acid, also known as vitamin B5 , was up-regulated. Finally, by integrating with transcriptomic data obtained by RNA-seq, we revealed enhanced steroid hormone biosynthesis during decidualization. Our study contributes to an increase in the knowledge on the molecular mechanisms of decidualization.
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Affiliation(s)
- Ji-Long Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, P. R. China
| | - Wen-Qian Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, P. R. China
| | - Miao Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, P. R. China
| | - Ming-Yu Huang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, P. R. China
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130
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Marnetto D, Mantica F, Molineris I, Grassi E, Pesando I, Provero P. Evolutionary Rewiring of Human Regulatory Networks by Waves of Genome Expansion. Am J Hum Genet 2018; 102:207-218. [PMID: 29357977 DOI: 10.1016/j.ajhg.2017.12.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 12/15/2017] [Indexed: 01/09/2023] Open
Abstract
Genome expansion is believed to be an important driver of the evolution of gene regulation. To investigate the role of a newly arising sequence in rewiring regulatory networks, we estimated the age of each region of the human genome by applying maximum parsimony to genome-wide alignments with 100 vertebrates. We then studied the age distribution of several types of functional regions, with a focus on regulatory elements. The age distribution of regulatory elements reveals the extensive use of newly formed genomic sequence in the evolution of regulatory interactions. Many transcription factors have expanded their repertoire of targets through waves of genomic expansions that can be traced to specific evolutionary times. Repeated elements contributed a major part of such expansion: many classes of such elements are enriched in binding sites of one or a few specific transcription factors, whose binding sites are localized in specific portions of the element and characterized by distinctive motif words. These features suggest that the binding sites were available as soon as the new sequence entered the genome, rather than being created later by accumulation of point mutations. By comparing the age of regulatory regions to the evolutionary shift in expression of nearby genes, we show that rewiring through genome expansion played an important role in shaping human regulatory networks.
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131
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Platt RN, Vandewege MW, Ray DA. Mammalian transposable elements and their impacts on genome evolution. Chromosome Res 2018; 26:25-43. [PMID: 29392473 PMCID: PMC5857283 DOI: 10.1007/s10577-017-9570-z] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 12/12/2017] [Accepted: 12/28/2017] [Indexed: 12/22/2022]
Abstract
Transposable elements (TEs) are genetic elements with the ability to mobilize and replicate themselves in a genome. Mammalian genomes are dominated by TEs, which can reach copy numbers in the hundreds of thousands. As a result, TEs have had significant impacts on mammalian evolution. Here we summarize the current understanding of TE content in mammal genomes and find that, with a few exceptions, most fall within a predictable range of observations. First, one third to one half of the genome is derived from TEs. Second, most mammalian genomes are dominated by LINE and SINE retrotransposons, more limited LTR retrotransposons, and minimal DNA transposon accumulation. Third, most mammal genome contains at least one family of actively accumulating retrotransposon. Finally, horizontal transfer of TEs among lineages is rare. TE exaptation events are being recognized with increasing frequency. Despite these beneficial aspects of TE content and activity, the majority of TE insertions are neutral or deleterious. To limit the deleterious effects of TE proliferation, the genome has evolved several defense mechanisms that act at the epigenetic, transcriptional, and post-transcriptional levels. The interaction between TEs and these defense mechanisms has led to an evolutionary arms race where TEs are suppressed, evolve to escape suppression, then are suppressed again as the defense mechanisms undergo compensatory change. The result is complex and constantly evolving interactions between TEs and host genomes.
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Affiliation(s)
- Roy N Platt
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.
| | | | - David A Ray
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA
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132
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Venuto D, Bourque G. Identifying co-opted transposable elements using comparative epigenomics. Dev Growth Differ 2018; 60:53-62. [PMID: 29363107 DOI: 10.1111/dgd.12423] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 12/08/2017] [Indexed: 12/19/2022]
Abstract
The human genome gives rise to different epigenomic landscapes that define each cell type and can be deregulated in disease. Recent efforts by ENCODE, the NIH Roadmap and the International Human Epigenome Consortium (IHEC) have made significant advances towards assembling reference epigenomic maps of various tissues. Notably, these projects have found that approximately 80% of human DNA was biochemically active in at least one epigenomic assay while only approximately 10% of the sequence displayed signs of purifying selection. Given that transposable elements (TEs) make up at least 50% of the human genome and can be actively transcribed or act as regulatory elements either for their own purposes or be co-opted for the benefit of their host; we are interested in exploring their overall contribution to the "functional" genome. Traditional methods used to identify functional DNA have relied on comparative genomics, conservation analysis and low throughput validation assays. To discover co-opted TEs, and distinguish them from noisy genomic elements, we argue that comparative epigenomic methods will also be important.
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Affiliation(s)
- David Venuto
- Department of Human Genetics, McGill University, Montréal, H3A 1B1, Québec, Canada
| | - Guillaume Bourque
- Department of Human Genetics, McGill University, Montréal, H3A 1B1, Québec, Canada.,Canadian Center for Computational Genomics, Montréal, H3A 0G1, Québec, Canada.,McGill University and Génome Québec Innovation Center, Montréal, H3A 0G1, Québec, Canada
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133
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Vrljicak P, Lucas ES, Lansdowne L, Lucciola R, Muter J, Dyer NP, Brosens JJ, Ott S. Analysis of chromatin accessibility in decidualizing human endometrial stromal cells. FASEB J 2018; 32:2467-2477. [PMID: 29259032 PMCID: PMC6040682 DOI: 10.1096/fj.201701098r] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Spontaneous decidualization of the endometrium in response to progesterone signaling is confined to menstruating species, including humans and other higher primates. During this process, endometrial stromal cells (EnSCs) differentiate into specialized decidual cells that control embryo implantation. We subjected undifferentiated and decidualizing human EnSCs to an assay for transposase accessible chromatin with sequencing (ATAC-seq) to map the underlying chromatin changes. A total of 185,084 open DNA loci were mapped accurately in EnSCs. Altered chromatin accessibility upon decidualization was strongly associated with differential gene expression. Analysis of 1533 opening and closing chromatin regions revealed over-representation of DNA binding motifs for known decidual transcription factors (TFs) and identified putative new regulators. ATAC-seq footprint analysis provided evidence of TF binding at specific motifs. One of the largest footprints involved the most enriched motif-basic leucine zipper-as part of a triple motif that also comprised the estrogen receptor and Pax domain binding sites. Without exception, triple motifs were located within Alu elements, which suggests a role for this primate-specific transposable element (TE) in the evolution of decidual genes. Although other TEs were generally under-represented in open chromatin of undifferentiated EnSCs, several classes contributed to the regulatory DNA landscape that underpins decidual gene expression.-Vrljicak, P., Lucas, E. S., Lansdowne, L., Lucciola, R., Muter, J., Dyer, N. P., Brosens, J. J., Ott, S. Analysis of chromatin accessibility in decidualizing human endometrial stromal cells.
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Affiliation(s)
- Pavle Vrljicak
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Emma S Lucas
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Lauren Lansdowne
- Department of Computer Science, University of Warwick, Coventry, United Kingdom
| | - Raffaella Lucciola
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Joanne Muter
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Nigel P Dyer
- Department of Computer Science, University of Warwick, Coventry, United Kingdom
| | - Jan J Brosens
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Sascha Ott
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Department of Computer Science, University of Warwick, Coventry, United Kingdom
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134
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Kojima KK. Human transposable elements in Repbase: genomic footprints from fish to humans. Mob DNA 2018; 9:2. [PMID: 29308093 PMCID: PMC5753468 DOI: 10.1186/s13100-017-0107-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 12/20/2017] [Indexed: 01/21/2023] Open
Abstract
Repbase is a comprehensive database of eukaryotic transposable elements (TEs) and repeat sequences, containing over 1300 human repeat sequences. Recent analyses of these repeat sequences have accumulated evidences for their contribution to human evolution through becoming functional elements, such as protein-coding regions or binding sites of transcriptional regulators. However, resolving the origins of repeat sequences is a challenge, due to their age, divergence, and degradation. Ancient repeats have been continuously classified as TEs by finding similar TEs from other organisms. Here, the most comprehensive picture of human repeat sequences is presented. The human genome contains traces of 10 clades (L1, CR1, L2, Crack, RTE, RTEX, R4, Vingi, Tx1 and Penelope) of non-long terminal repeat (non-LTR) retrotransposons (long interspersed elements, LINEs), 3 types (SINE1/7SL, SINE2/tRNA, and SINE3/5S) of short interspersed elements (SINEs), 1 composite retrotransposon (SVA) family, 5 classes (ERV1, ERV2, ERV3, Gypsy and DIRS) of LTR retrotransposons, and 12 superfamilies (Crypton, Ginger1, Harbinger, hAT, Helitron, Kolobok, Mariner, Merlin, MuDR, P, piggyBac and Transib) of DNA transposons. These TE footprints demonstrate an evolutionary continuum of the human genome.
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Affiliation(s)
- Kenji K Kojima
- Genetic Information Research Institute, 465 Fairchild Drive, Suite 201, Mountain View, CA 94043 USA.,Department of Life Sciences, National Cheng Kung University, No. 1, Daxue Rd, East District, Tainan, 701 Taiwan
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135
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Benchouaia M, Ripoche H, Sissoko M, Thiébaut A, Merhej J, Delaveau T, Fasseu L, Benaissa S, Lorieux G, Jourdren L, Le Crom S, Lelandais G, Corel E, Devaux F. Comparative Transcriptomics Highlights New Features of the Iron Starvation Response in the Human Pathogen Candida glabrata. Front Microbiol 2018; 9:2689. [PMID: 30505294 PMCID: PMC6250833 DOI: 10.3389/fmicb.2018.02689] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 10/22/2018] [Indexed: 11/21/2022] Open
Abstract
In this work, we used comparative transcriptomics to identify regulatory outliers (ROs) in the human pathogen Candida glabrata. ROs are genes that have very different expression patterns compared to their orthologs in other species. From comparative transcriptome analyses of the response of eight yeast species to toxic doses of selenite, a pleiotropic stress inducer, we identified 38 ROs in C. glabrata. Using transcriptome analyses of C. glabrata response to five different stresses, we pointed out five ROs which were more particularly responsive to iron starvation, a process which is very important for C. glabrata virulence. Global chromatin Immunoprecipitation and gene profiling analyses showed that four of these genes are actually new targets of the iron starvation responsive Aft2 transcription factor in C. glabrata. Two of them (HBS1 and DOM34b) are required for C. glabrata optimal growth in iron limited conditions. In S. cerevisiae, the orthologs of these two genes are involved in ribosome rescue by the NO GO decay (NGD) pathway. Hence, our results suggest a specific contribution of NGD co-factors to the C. glabrata adaptation to iron starvation.
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Affiliation(s)
- Médine Benchouaia
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Hugues Ripoche
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Mariam Sissoko
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Antonin Thiébaut
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Jawad Merhej
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Thierry Delaveau
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Laure Fasseu
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Sabrina Benaissa
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Geneviève Lorieux
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
| | - Laurent Jourdren
- École Normale Supérieure, PSL Research University, CNRS, Inserm U1024, Institut de Biologie de l’École Normale Supérieure, Plateforme Génomique, Paris, France
| | - Stéphane Le Crom
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7138, Évolution, Paris, France
| | - Gaëlle Lelandais
- UMR 9198, Institute for Integrative Biology of the Cell, CEA, CNRS, Université Paris-Sud, UPSay, Gif-sur-Yvette, France
| | - Eduardo Corel
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7138, Évolution, Paris, France
| | - Frédéric Devaux
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, UMR 7238, Laboratoire de Biologie Computationnelle et Quantitative, Paris, France
- *Correspondence: Frédéric Devaux,
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136
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Sundaram V, Wang T. Transposable Element Mediated Innovation in Gene Regulatory Landscapes of Cells: Re-Visiting the "Gene-Battery" Model. Bioessays 2018; 40:10.1002/bies.201700155. [PMID: 29206283 PMCID: PMC5912915 DOI: 10.1002/bies.201700155] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 10/25/2017] [Indexed: 01/31/2023]
Abstract
Transposable elements (TEs) are no longer considered to be "junk" DNA. Here, we review how TEs can impact gene regulation systematically. TEs encode various regulatory elements that enables them to regulate gene expression. RJ Britten and EH Davidson hypothesized that TEs can integrate the function of various transcriptional regulators into gene regulatory networks. Uniquely TEs can deposit regulatory sites across the genome when they transpose, and thereby bring multiple genes under control of the same regulatory logic. Several studies together have robustly established that TEs participate in embryonic development and oncogenesis. We discuss the regulatory characteristics of TEs in context of evolution to understand the extent of their impact on gene networks. Understanding these features of TEs is central to future investigations of TEs in cellular processes and phenotypic presentations, which are applicable to development and disease studies. We re-visit the Britten-Davidson "gene-battery" model and understand the genetic and transcriptional impact of TEs in innovating gene regulatory networks.
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Affiliation(s)
- Vasavi Sundaram
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, United Kingdom
| | - Ting Wang
- Department of Genetics, Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St Louis, Missouri 63110, United States of America
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137
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Shapiro JA. Living Organisms Author Their Read-Write Genomes in Evolution. BIOLOGY 2017; 6:E42. [PMID: 29211049 PMCID: PMC5745447 DOI: 10.3390/biology6040042] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/17/2017] [Accepted: 11/28/2017] [Indexed: 12/18/2022]
Abstract
Evolutionary variations generating phenotypic adaptations and novel taxa resulted from complex cellular activities altering genome content and expression: (i) Symbiogenetic cell mergers producing the mitochondrion-bearing ancestor of eukaryotes and chloroplast-bearing ancestors of photosynthetic eukaryotes; (ii) interspecific hybridizations and genome doublings generating new species and adaptive radiations of higher plants and animals; and, (iii) interspecific horizontal DNA transfer encoding virtually all of the cellular functions between organisms and their viruses in all domains of life. Consequently, assuming that evolutionary processes occur in isolated genomes of individual species has become an unrealistic abstraction. Adaptive variations also involved natural genetic engineering of mobile DNA elements to rewire regulatory networks. In the most highly evolved organisms, biological complexity scales with "non-coding" DNA content more closely than with protein-coding capacity. Coincidentally, we have learned how so-called "non-coding" RNAs that are rich in repetitive mobile DNA sequences are key regulators of complex phenotypes. Both biotic and abiotic ecological challenges serve as triggers for episodes of elevated genome change. The intersections of cell activities, biosphere interactions, horizontal DNA transfers, and non-random Read-Write genome modifications by natural genetic engineering provide a rich molecular and biological foundation for understanding how ecological disruptions can stimulate productive, often abrupt, evolutionary transformations.
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Affiliation(s)
- James A Shapiro
- Department of Biochemistry and Molecular Biology, University of Chicago GCIS W123B, 979 E. 57th Street, Chicago, IL 60637, USA.
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138
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Stearns SC. Outstanding research opportunities at the interface of evolution and medicine. Nat Ecol Evol 2017; 2:3-4. [PMID: 29180708 DOI: 10.1038/s41559-017-0409-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Stephen C Stearns
- Department of Ecology and Evolutionary Biology, Yale University, Box 208106, New Haven, CT, 06520, USA.
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139
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Simonti CN, Pavličev M, Capra JA. Transposable Element Exaptation into Regulatory Regions Is Rare, Influenced by Evolutionary Age, and Subject to Pleiotropic Constraints. Mol Biol Evol 2017; 34:2856-2869. [PMID: 28961735 PMCID: PMC5850124 DOI: 10.1093/molbev/msx219] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Transposable element (TE)-derived sequences make up approximately half of most mammalian genomes, and many TEs have been co-opted into gene regulatory elements. However, we lack a comprehensive tissue- and genome-wide understanding of how and when TEs gain regulatory activity in their hosts. We evaluated the prevalence of TE-derived DNA in enhancers and promoters across hundreds of human and mouse cell lines and primary tissues. Promoters are significantly depleted of TEs in all tissues compared with their overall prevalence in the genome (P < 0.001); enhancers are also depleted of TEs, though not as strongly as promoters. The degree of enhancer depletion also varies across contexts (1.5-3×), with reproductive and immune cells showing the highest levels of TE regulatory activity in humans. Overall, in spite of the regulatory potential of many TE sequences, they are significantly less active in gene regulation than expected from their prevalence. TE age is predictive of the likelihood of enhancer activity; TEs originating before the divergence of amniotes are 9.2 times more likely to have enhancer activity than TEs that integrated in great apes. Context-specific enhancers are more likely to be TE-derived than enhancers active in multiple tissues, and young TEs are more likely to overlap context-specific enhancers than old TEs (86% vs. 47%). Once TEs obtain enhancer activity in the host, they have similar functional dynamics to one another and non-TE-derived enhancers, likely driven by pleiotropic constraints. However, a few TE families, most notably endogenous retroviruses, have greater regulatory potential. Our observations suggest a model of regulatory co-option in which TE-derived sequences are initially repressed, after which a small fraction obtains context-specific enhancer activity, with further gains subject to pleiotropic constraints.
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Affiliation(s)
| | - Mihaela Pavličev
- Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH
| | - John A. Capra
- Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN
- Department of Biological Sciences, Vanderbilt University, Nashville, TN
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140
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Brosens I, Muter J, Gargett CE, Puttemans P, Benagiano G, Brosens JJ. The impact of uterine immaturity on obstetrical syndromes during adolescence. Am J Obstet Gynecol 2017; 217:546-555. [PMID: 28578177 DOI: 10.1016/j.ajog.2017.05.059] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 05/09/2017] [Accepted: 05/24/2017] [Indexed: 12/21/2022]
Abstract
Pregnant nulliparous adolescents are at increased risk, inversely proportional to their age, of major obstetric syndromes, including preeclampsia, fetal growth restriction, and preterm birth. Emerging evidence indicates that biological immaturity of the uterus accounts for the increased incidence of obstetrical disorders in very young mothers, possibly compounded by sociodemographic factors associated with teenage pregnancy. The endometrium in most newborns is intrinsically resistant to progesterone signaling, and the rate of transition to a fully responsive tissue likely determines pregnancy outcome during adolescence. In addition to ontogenetic progesterone resistance, other factors appear important for the transition of the immature uterus to a functional organ, including estrogen-dependent growth and tissue-specific conditioning of uterine natural killer cells, which plays a critical role in vascular adaptation during pregnancy. The perivascular space around the spiral arteries is rich in endometrial mesenchymal stem-like cells, and dynamic changes in this niche are essential to accommodate endovascular trophoblast invasion and deep placentation. Here we evaluate the intrinsic (uterine-specific) mechanisms that predispose adolescent mothers to the great obstetrical syndromes and discuss the convergence of extrinsic risk factors that may be amenable to intervention.
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Affiliation(s)
- Ivo Brosens
- Faculty of Medicine, Catholic University of Leuven, Leuven, Belgium.
| | - Joanne Muter
- Division of Biomedical Sciences, Warwick Medical School, Coventry, United Kingdom
| | - Caroline E Gargett
- Ritchie Centre, Hudson Institute of Medical Research, Melbourne, and Department of Obstetrics and Gynaecology, Monash University, Victoria, Australia
| | | | - Giuseppe Benagiano
- Department of Gynecology, Obstetrics, and Urology, Sapienza, University of Rome, Rome, Italy
| | - Jan J Brosens
- Division of Biomedical Sciences, Warwick Medical School, Coventry, United Kingdom
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141
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Trizzino M, Park Y, Holsbach-Beltrame M, Aracena K, Mika K, Caliskan M, Perry GH, Lynch VJ, Brown CD. Transposable elements are the primary source of novelty in primate gene regulation. Genome Res 2017; 27:1623-1633. [PMID: 28855262 PMCID: PMC5630026 DOI: 10.1101/gr.218149.116] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 08/17/2017] [Indexed: 12/11/2022]
Abstract
Gene regulation shapes the evolution of phenotypic diversity. We investigated the evolution of liver promoters and enhancers in six primate species using ChIP-seq (H3K27ac and H3K4me1) to profile cis-regulatory elements (CREs) and using RNA-seq to characterize gene expression in the same individuals. To quantify regulatory divergence, we compared CRE activity across species by testing differential ChIP-seq read depths directly measured for orthologous sequences. We show that the primate regulatory landscape is largely conserved across the lineage, with 63% of the tested human liver CREs showing similar activity across species. Conserved CRE function is associated with sequence conservation, proximity to coding genes, cell-type specificity, and transcription factor binding. Newly evolved CREs are enriched in immune response and neurodevelopmental functions. We further demonstrate that conserved CREs bind master regulators, suggesting that while CREs contribute to species adaptation to the environment, core functions remain intact. Newly evolved CREs are enriched in young transposable elements (TEs), including Long-Terminal-Repeats (LTRs) and SINE-VNTR-Alus (SVAs), that significantly affect gene expression. Conversely, only 16% of conserved CREs overlap TEs. We tested the cis-regulatory activity of 69 TE subfamilies by luciferase reporter assays, spanning all major TE classes, and showed that 95.6% of tested TEs can function as either transcriptional activators or repressors. In conclusion, we demonstrated the critical role of TEs in primate gene regulation and illustrated potential mechanisms underlying evolutionary divergence among the primate species through the noncoding genome.
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Affiliation(s)
- Marco Trizzino
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Institute for Biomedical Informatics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - YoSon Park
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Institute for Biomedical Informatics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Marcia Holsbach-Beltrame
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Katherine Aracena
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Katelyn Mika
- Department of Human Genetics, University of Chicago, Chicago, Illinois 60637, USA
| | - Minal Caliskan
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Institute for Biomedical Informatics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - George H Perry
- Departments of Anthropology and Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Vincent J Lynch
- Department of Human Genetics, University of Chicago, Chicago, Illinois 60637, USA
| | - Christopher D Brown
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Institute for Biomedical Informatics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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142
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Dong Y, Huang Z, Kuang Q, Wen Z, Liu Z, Li Y, Yang Y, Li M. Expression dynamics and relations with nearby genes of rat transposable elements across 11 organs, 4 developmental stages and both sexes. BMC Genomics 2017; 18:666. [PMID: 28851270 PMCID: PMC5576108 DOI: 10.1186/s12864-017-4078-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/21/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND TEs pervade mammalian genomes. However, compared with mice, fewer studies have focused on the TE expression patterns in rat, particularly the comparisons across different organs, developmental stages and sexes. In addition, TEs can influence the expression of nearby genes. The temporal and spatial influences of TEs remain unclear yet. RESULTS To evaluate the TEs transcription patterns, we profiled their transcript levels in 11 organs for both sexes across four developmental stages of rat. The results show that most short interspersed elements (SINEs) are commonly expressed in all conditions, which are also the major TE types with commonly expression patterns. In contrast, long terminal repeats (LTRs) are more likely to exhibit specific expression patterns. The expression tendency of TEs and genes are similar in most cases. For example, few specific genes and TEs are in the liver, muscle and heart. However, TEs perform superior over genes on classing organ, which imply their higher organ specificity than genes. By associating the TEs with the closest genes in genome, we find their expression levels are correlated, independent of their distance in some cases. CONCLUSIONS TEs sex-dependently associate with nearest genes. A gene would be associated with more than one TE. Our works can help to functionally annotate the genome and further understand the role of TEs in gene regulation.
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Affiliation(s)
- Yongcheng Dong
- College of Life Science, Sichuan University, Chengdu, 610064, China
| | - Ziyan Huang
- College of Chemistry, Sichuan University, Chengdu, 610064, China
| | - Qifan Kuang
- College of Chemistry, Sichuan University, Chengdu, 610064, China
| | - Zhining Wen
- College of Chemistry, Sichuan University, Chengdu, 610064, China
| | - Zhibin Liu
- College of Life Science, Sichuan University, Chengdu, 610064, China
| | - Yizhou Li
- College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | - Yi Yang
- College of Life Science, Sichuan University, Chengdu, 610064, China.
| | - Menglong Li
- College of Chemistry, Sichuan University, Chengdu, 610064, China
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143
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Zhang S, Kelleher ES. Targeted identification of TE insertions in a Drosophila genome through hemi-specific PCR. Mob DNA 2017; 8:10. [PMID: 28775768 PMCID: PMC5534036 DOI: 10.1186/s13100-017-0092-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 07/10/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transposable elements (TEs) are major components of eukaryotic genomes and drivers of genome evolution, producing intraspecific polymorphism and interspecific differences through mobilization and non-homologous recombination. TE insertion sites are often highly variable within species, creating a need for targeted genome re-sequencing (TGS) methods to identify TE insertion sites. METHODS We present a hemi-specific PCR approach for TGS of P-elements in Drosophila genomes on the Illumina platform. We also present a computational framework for identifying new insertions from TGS reads. Finally, we describe a new method for estimating the frequency of TE insertions from WGS data, which is based precise insertion sites provided by TGS annotations. RESULTS By comparing our results to TE annotations based on whole genome re-sequencing (WGS) data for the same Drosophilamelanogaster strain, we demonstrate that TGS is powerful for identifying true insertions, even in repeat-rich heterochromatic regions. We also demonstrate that TGS offers enhanced annotation of precise insertion sites, which facilitates estimation of TE insertion frequency. CONCLUSIONS TGS by hemi-specific PCR is a powerful approach for identifying TE insertions of particular TE families in species with a high-quality reference genome, at greatly reduced cost as compared to WGS. It may therefore be ideal for population genomic studies of particular TE families. Additionally, TGS and WGS can be used as complementary approaches, with TGS annotations identifying more annotated insertions with greater precision for a target TE family, and WGS data allowing for estimates of TE insertion frequencies, and a broader picture of the location of non-target TEs across the genome.
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Affiliation(s)
- Shuo Zhang
- Department of Biology and Biochemistry, University of Houston, 3455 Cullen Blvd. Suite 342, Houston, TX 77204 USA
| | - Erin S. Kelleher
- Department of Biology and Biochemistry, University of Houston, 3455 Cullen Blvd. Suite 342, Houston, TX 77204 USA
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144
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Affiliation(s)
- Haig H Kazazian
- From the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore (H.H.K.), and the Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor (J.V.M.)
| | - John V Moran
- From the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins School of Medicine, Baltimore (H.H.K.), and the Departments of Human Genetics and Internal Medicine, University of Michigan Medical School, Ann Arbor (J.V.M.)
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145
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Eidem HR, McGary KL, Capra JA, Abbot P, Rokas A. The transformative potential of an integrative approach to pregnancy. Placenta 2017; 57:204-215. [PMID: 28864013 DOI: 10.1016/j.placenta.2017.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 07/08/2017] [Accepted: 07/15/2017] [Indexed: 11/17/2022]
Abstract
BACKGROUND Complex traits typically involve diverse biological pathways and are shaped by numerous genetic and environmental factors. Pregnancy-associated traits and pathologies are further complicated by extensive communication across multiple tissues in two individuals, interactions between two genomes-maternal and fetal-that obscure causal variants and lead to genetic conflict, and rapid evolution of pregnancy-associated traits across mammals and in the human lineage. Given the multi-faceted complexity of human pregnancy, integrative approaches that synthesize diverse data types and analyses harbor tremendous promise to identify the genetic architecture and environmental influences underlying pregnancy-associated traits and pathologies. METHODS We review current research that addresses the extreme complexities of traits and pathologies associated with human pregnancy. RESULTS We find that successful efforts to address the many complexities of pregnancy-associated traits and pathologies often harness the power of many and diverse types of data, including genome-wide association studies, evolutionary analyses, multi-tissue transcriptomic profiles, and environmental conditions. CONCLUSION We propose that understanding of pregnancy and its pathologies will be accelerated by computational platforms that provide easy access to integrated data and analyses. By simplifying the integration of diverse data, such platforms will provide a comprehensive synthesis that transcends many of the inherent challenges present in studies of pregnancy.
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Affiliation(s)
- Haley R Eidem
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
| | - Kriston L McGary
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
| | - John A Capra
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA; Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN 37235, USA
| | - Patrick Abbot
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA; Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN 37235, USA.
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146
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Silencing of Transposable Elements by piRNAs in Drosophila: An Evolutionary Perspective. GENOMICS PROTEOMICS & BIOINFORMATICS 2017; 15:164-176. [PMID: 28602845 PMCID: PMC5487533 DOI: 10.1016/j.gpb.2017.01.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 01/02/2017] [Accepted: 01/12/2017] [Indexed: 11/28/2022]
Abstract
Transposable elements (TEs) are DNA sequences that can move within the genome. TEs have greatly shaped the genomes, transcriptomes, and proteomes of the host organisms through a variety of mechanisms. However, TEs generally disrupt genes and destabilize the host genomes, which substantially reduce fitness of the host organisms. Understanding the genomic distribution and evolutionary dynamics of TEs will greatly deepen our understanding of the TE-mediated biological processes. Most TE insertions are highly polymorphic in Drosophila melanogaster, providing us a good system to investigate the evolution of TEs at the population level. Decades of theoretical and experimental studies have well established “transposition-selection” population genetics model, which assumes that the equilibrium between TE replication and purifying selection determines the copy number of TEs in the genome. In the last decade, P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) were demonstrated to be master repressors of TE activities in Drosophila. The discovery of piRNAs revolutionized our understanding of TE repression, because it reveals that the host organisms have evolved an adaptive mechanism to defend against TE invasion. Tremendous progress has been made to understand the molecular mechanisms by which piRNAs repress active TEs, although many details in this process remain to be further explored. The interaction between piRNAs and TEs well explains the molecular mechanisms underlying hybrid dysgenesis for the I-R and P-M systems in Drosophila, which have puzzled evolutionary biologists for decades. The piRNA repression pathway provides us an unparalleled system to study the co-evolutionary process between parasites and host organisms.
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147
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Reexamining the P-Element Invasion of Drosophila melanogaster Through the Lens of piRNA Silencing. Genetics 2017; 203:1513-31. [PMID: 27516614 DOI: 10.1534/genetics.115.184119] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 05/25/2016] [Indexed: 11/18/2022] Open
Abstract
Transposable elements (TEs) are both important drivers of genome evolution and genetic parasites with potentially dramatic consequences for host fitness. The recent explosion of research on regulatory RNAs reveals that small RNA-mediated silencing is a conserved genetic mechanism through which hosts repress TE activity. The invasion of the Drosophila melanogaster genome by P elements, which happened on a historical timescale, represents an incomparable opportunity to understand how small RNA-mediated silencing of TEs evolves. Repression of P-element transposition emerged almost concurrently with its invasion. Recent studies suggest that this repression is implemented in part, and perhaps predominantly, by the Piwi-interacting RNA (piRNA) pathway, a small RNA-mediated silencing pathway that regulates TE activity in many metazoan germlines. In this review, I consider the P-element invasion from both a molecular and evolutionary genetic perspective, reconciling classic studies of P-element regulation with the new mechanistic framework provided by the piRNA pathway. I further explore the utility of the P-element invasion as an exemplar of the evolution of piRNA-mediated silencing. In light of the highly-conserved role for piRNAs in regulating TEs, discoveries from this system have taxonomically broad implications for the evolution of repression.
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148
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Rebeiz M, Tsiantis M. Enhancer evolution and the origins of morphological novelty. Curr Opin Genet Dev 2017; 45:115-123. [PMID: 28527813 DOI: 10.1016/j.gde.2017.04.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/25/2017] [Accepted: 04/27/2017] [Indexed: 01/07/2023]
Abstract
A central goal of evolutionary biology is to understand the genetic origin of morphological novelties-i.e. anatomical structures unique to a taxonomic group. Elaboration of morphology during development depends on networks of regulatory genes that activate patterned gene expression through transcriptional enhancer regions. We summarize recent case studies and genome-wide investigations that have uncovered diverse mechanisms though which new enhancers arise. We also discuss how these enhancer-originating mechanisms have clarified the history of genetic networks underlying diversification of genital structures in flies, limbs and neural crest in chordates, and plant leaves. These studies have identified enhancers that were pivotal for morphological divergence and highlighted how novel genetic networks shaping form emerged from pre-existing ones.
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Affiliation(s)
- Mark Rebeiz
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15215, USA.
| | - Miltos Tsiantis
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, 50829 Köln, Germany.
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149
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Blinov VM, Zverev VV, Krasnov GS, Filatov FP, Shargunov AV. Viral component of the human genome. Mol Biol 2017; 51:205-215. [PMID: 32214476 PMCID: PMC7089383 DOI: 10.1134/s0026893317020066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 04/27/2016] [Indexed: 12/17/2022]
Abstract
Relationships between viruses and their human host are traditionally described from the point of view taking into consideration hosts as victims of viral aggression, which results in infectious diseases. However, these relations are in fact two-sided and involve modifications of both the virus and host genomes. Mutations that accumulate in the populations of viruses and hosts may provide them advantages such as the ability to overcome defense barriers of host cells or to create more efficient barriers to deal with the attack of the viral agent. One of the most common ways of reinforcing anti-viral barriers is the horizontal transfer of viral genes into the host genome. Within the host genome, these genes may be modified and extensively expressed to compete with viral copies and inhibit the synthesis of their products or modulate their functions in other ways. This review summarizes the available data on the horizontal gene transfer between viral and human genomes and discusses related problems.
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Affiliation(s)
- V M Blinov
- 1Mechnikov Research Institute of Vaccines and Sera, Moscow, 105064 Russia
| | - V V Zverev
- 1Mechnikov Research Institute of Vaccines and Sera, Moscow, 105064 Russia
| | - G S Krasnov
- 1Mechnikov Research Institute of Vaccines and Sera, Moscow, 105064 Russia.,2Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 111911 Russia.,3Orekhovich Research Institute of Biomedical Chemistry, Moscow, 119121 Russia
| | - F P Filatov
- 1Mechnikov Research Institute of Vaccines and Sera, Moscow, 105064 Russia.,Gamaleya Research Center of Epidemiology and Microbiology, Moscow, 123098 Russia
| | - A V Shargunov
- 1Mechnikov Research Institute of Vaccines and Sera, Moscow, 105064 Russia
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150
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Sundaram V, Choudhary MNK, Pehrsson E, Xing X, Fiore C, Pandey M, Maricque B, Udawatta M, Ngo D, Chen Y, Paguntalan A, Ray T, Hughes A, Cohen BA, Wang T. Functional cis-regulatory modules encoded by mouse-specific endogenous retrovirus. Nat Commun 2017; 8:14550. [PMID: 28348391 PMCID: PMC5379053 DOI: 10.1038/ncomms14550] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 01/11/2017] [Indexed: 01/30/2023] Open
Abstract
Cis-regulatory modules contain multiple transcription factor (TF)-binding sites and integrate the effects of each TF to control gene expression in specific cellular contexts. Transposable elements (TEs) are uniquely equipped to deposit their regulatory sequences across a genome, which could also contain cis-regulatory modules that coordinate the control of multiple genes with the same regulatory logic. We provide the first evidence of mouse-specific TEs that encode a module of TF-binding sites in mouse embryonic stem cells (ESCs). The majority (77%) of the individual TEs tested exhibited enhancer activity in mouse ESCs. By mutating individual TF-binding sites within the TE, we identified a module of TF-binding motifs that cooperatively enhanced gene expression. Interestingly, we also observed the same motif module in the in silico constructed ancestral TE that also acted cooperatively to enhance gene expression. Our results suggest that ancestral TE insertions might have brought in cis-regulatory modules into the mouse genome.
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Affiliation(s)
- Vasavi Sundaram
- Division of Biological and Biomedical Sciences, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, USA
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Mayank N. K. Choudhary
- Division of Biological and Biomedical Sciences, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, USA
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Erica Pehrsson
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Xiaoyun Xing
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Christopher Fiore
- Division of Biological and Biomedical Sciences, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, USA
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Manishi Pandey
- Division of Biological and Biomedical Sciences, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, USA
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Brett Maricque
- Division of Biological and Biomedical Sciences, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, USA
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Methma Udawatta
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Duc Ngo
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Yujie Chen
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Asia Paguntalan
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Tammy Ray
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Ava Hughes
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Barak A. Cohen
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
| | - Ting Wang
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, St. Louis, Missouri 63110, USA
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