1
|
Xu L, Liu Y. Identification, Design, and Application of Noncoding Cis-Regulatory Elements. Biomolecules 2024; 14:945. [PMID: 39199333 PMCID: PMC11352686 DOI: 10.3390/biom14080945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 07/25/2024] [Accepted: 07/30/2024] [Indexed: 09/01/2024] Open
Abstract
Cis-regulatory elements (CREs) play a pivotal role in orchestrating interactions with trans-regulatory factors such as transcription factors, RNA-binding proteins, and noncoding RNAs. These interactions are fundamental to the molecular architecture underpinning complex and diverse biological functions in living organisms, facilitating a myriad of sophisticated and dynamic processes. The rapid advancement in the identification and characterization of these regulatory elements has been marked by initiatives such as the Encyclopedia of DNA Elements (ENCODE) project, which represents a significant milestone in the field. Concurrently, the development of CRE detection technologies, exemplified by massively parallel reporter assays, has progressed at an impressive pace, providing powerful tools for CRE discovery. The exponential growth of multimodal functional genomic data has necessitated the application of advanced analytical methods. Deep learning algorithms, particularly large language models, have emerged as invaluable tools for deconstructing the intricate nucleotide sequences governing CRE function. These advancements facilitate precise predictions of CRE activity and enable the de novo design of CREs. A deeper understanding of CRE operational dynamics is crucial for harnessing their versatile regulatory properties. Such insights are instrumental in refining gene therapy techniques, enhancing the efficacy of selective breeding programs, pushing the boundaries of genetic innovation, and opening new possibilities in microbial synthetic biology.
Collapse
Affiliation(s)
- Lingna Xu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China;
- Innovation Group of Pig Genome Design and Breeding, Research Centre for Animal Genome, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China
| | - Yuwen Liu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China;
- Innovation Group of Pig Genome Design and Breeding, Research Centre for Animal Genome, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China
- Kunpeng Institute of Modern Agriculture at Foshan, Chinese Academy of Agricultural Sciences, Foshan 528226, China
| |
Collapse
|
2
|
Czapiewski R, Schirmer EC. Enhancers on the edge - how the nuclear envelope controls gene regulatory elements. Curr Opin Genet Dev 2024; 87:102234. [PMID: 39047586 DOI: 10.1016/j.gde.2024.102234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 06/20/2024] [Accepted: 07/05/2024] [Indexed: 07/27/2024]
Abstract
Precise temporal and sequential control of gene expression during development and in response to environmental stimuli requires tight regulation of the physical contact between gene regulatory elements and promoters. Current models describing how the genome folds in 3D space to establish these interactions often ignore the role of the most stable structural nuclear feature - the nuclear envelope. While contributions of 3D folding within/between topologically associated domains (TADs) have been extensively described, mechanical contributions from the nuclear envelope can impact enhancer-promoter interactions both directly and indirectly through influencing intra/inter-TAD interactions. Importantly, these nuclear envelope contributions clearly link this mechanism to development and, when defective, to human disease. Here, we discuss evidence for nuclear envelope regulation of tissue-specific enhancer-promoter pairings, potential mechanisms for this regulation, exciting recent findings that other regulatory elements such as microRNAs and long noncoding RNAs are under nuclear envelope regulation, the possible involvement of condensates, and how disruption of this regulation can lead to disease.
Collapse
Affiliation(s)
- Rafal Czapiewski
- Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom; MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom.
| | - Eric C Schirmer
- Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom.
| |
Collapse
|
3
|
Iñiguez-Muñoz S, Llinàs-Arias P, Ensenyat-Mendez M, Bedoya-López AF, Orozco JIJ, Cortés J, Roy A, Forsberg-Nilsson K, DiNome ML, Marzese DM. Hidden secrets of the cancer genome: unlocking the impact of non-coding mutations in gene regulatory elements. Cell Mol Life Sci 2024; 81:274. [PMID: 38902506 PMCID: PMC11335195 DOI: 10.1007/s00018-024-05314-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 12/07/2023] [Accepted: 06/06/2024] [Indexed: 06/22/2024]
Abstract
Discoveries in the field of genomics have revealed that non-coding genomic regions are not merely "junk DNA", but rather comprise critical elements involved in gene expression. These gene regulatory elements (GREs) include enhancers, insulators, silencers, and gene promoters. Notably, new evidence shows how mutations within these regions substantially influence gene expression programs, especially in the context of cancer. Advances in high-throughput sequencing technologies have accelerated the identification of somatic and germline single nucleotide mutations in non-coding genomic regions. This review provides an overview of somatic and germline non-coding single nucleotide alterations affecting transcription factor binding sites in GREs, specifically involved in cancer biology. It also summarizes the technologies available for exploring GREs and the challenges associated with studying and characterizing non-coding single nucleotide mutations. Understanding the role of GRE alterations in cancer is essential for improving diagnostic and prognostic capabilities in the precision medicine era, leading to enhanced patient-centered clinical outcomes.
Collapse
Affiliation(s)
- Sandra Iñiguez-Muñoz
- Cancer Epigenetics Laboratory at the Cancer Cell Biology Group, Institut d'Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
| | - Pere Llinàs-Arias
- Cancer Epigenetics Laboratory at the Cancer Cell Biology Group, Institut d'Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
| | - Miquel Ensenyat-Mendez
- Cancer Epigenetics Laboratory at the Cancer Cell Biology Group, Institut d'Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
| | - Andrés F Bedoya-López
- Cancer Epigenetics Laboratory at the Cancer Cell Biology Group, Institut d'Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
| | - Javier I J Orozco
- Saint John's Cancer Institute, Providence Saint John's Health Center, Santa Monica, CA, USA
| | - Javier Cortés
- International Breast Cancer Center (IBCC), Pangaea Oncology, Quiron Group, 08017, Barcelona, Spain
- Medica Scientia Innovation Research SL (MEDSIR), 08018, Barcelona, Spain
- Faculty of Biomedical and Health Sciences, Department of Medicine, Universidad Europea de Madrid, 28670, Madrid, Spain
| | - Ananya Roy
- Department of Immunology, Genetics and Pathology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Karin Forsberg-Nilsson
- Department of Immunology, Genetics and Pathology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
- University of Nottingham Biodiscovery Institute, Nottingham, UK
| | - Maggie L DiNome
- Department of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - Diego M Marzese
- Cancer Epigenetics Laboratory at the Cancer Cell Biology Group, Institut d'Investigació Sanitària Illes Balears (IdISBa), Palma, Spain.
- Department of Surgery, Duke University School of Medicine, Durham, NC, USA.
| |
Collapse
|
4
|
Chang TY, Waxman DJ. HDI-STARR-seq: Condition-specific enhancer discovery in mouse liver in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.10.598329. [PMID: 38915578 PMCID: PMC11195054 DOI: 10.1101/2024.06.10.598329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
STARR-seq and other massively-parallel reporter assays are widely used to discover functional enhancers in transfected cell models, which can be confounded by plasmid vector-induced type-I interferon immune responses and lack the multicellular environment and endogenous chromatin state of complex mammalian tissues. Here, we describe HDI-STARR-seq, which combines STARR-seq plasmid library delivery to the liver, by hydrodynamic tail vein injection (HDI), with reporter RNA transcriptional initiation driven by a minimal Albumin promoter, which we show is essential for mouse liver STARR-seq enhancer activity assayed 7 days after HDI. Importantly, little or no vector-induced innate type-I interferon responses were observed. Comparisons of HDI-STARR-seq activity between male and female mouse livers and in livers from males treated with an activating ligand of the transcription factor CAR (Nr1i3) identified many condition-dependent enhancers linked to condition-specific gene expression. Further, thousands of active liver enhancers were identified using a high complexity STARR-seq library comprised of ~50,000 genomic regions released by DNase-I digestion of mouse liver nuclei. When compared to stringently inactive library sequences, the active enhancer sequences identified were highly enriched for liver open chromatin regions with activating histone marks (H3K27ac, H3K4me1, H3K4me3), were significantly closer to gene transcriptional start sites, and were significantly depleted of repressive (H3K27me3, H3K9me3) and transcribed region histone marks (H3K36me3). HDI-STARR-seq offers substantial improvements over current methodologies for large scale, functional profiling of enhancers, including condition-dependent enhancers, in liver tissue in vivo, and can be adapted to characterize enhancer activities in a variety of species and tissues by selecting suitable tissue- and species-specific promoter sequences.
Collapse
Affiliation(s)
- Ting-Ya Chang
- Departments of Biology and Biomedical Engineering, and Bioinformatics program, Boston University, Boston, MA 02215
| | - David J Waxman
- Departments of Biology and Biomedical Engineering, and Bioinformatics program, Boston University, Boston, MA 02215
| |
Collapse
|
5
|
Chin IM, Gardell ZA, Corces MR. Decoding polygenic diseases: advances in noncoding variant prioritization and validation. Trends Cell Biol 2024; 34:465-483. [PMID: 38719704 DOI: 10.1016/j.tcb.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 03/12/2024] [Accepted: 03/21/2024] [Indexed: 06/09/2024]
Abstract
Genome-wide association studies (GWASs) provide a key foundation for elucidating the genetic underpinnings of common polygenic diseases. However, these studies have limitations in their ability to assign causality to particular genetic variants, especially those residing in the noncoding genome. Over the past decade, technological and methodological advances in both analytical and empirical prioritization of noncoding variants have enabled the identification of causative variants by leveraging orthogonal functional evidence at increasing scale. In this review, we present an overview of these approaches and describe how this workflow provides the groundwork necessary to move beyond associations toward genetically informed studies on the molecular and cellular mechanisms of polygenic disease.
Collapse
Affiliation(s)
- Iris M Chin
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, USA; Gladstone Institute of Data Science and Biotechnology, Gladstone Institutes, San Francisco, CA, USA; Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Zachary A Gardell
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, USA; Gladstone Institute of Data Science and Biotechnology, Gladstone Institutes, San Francisco, CA, USA; Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - M Ryan Corces
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, USA; Gladstone Institute of Data Science and Biotechnology, Gladstone Institutes, San Francisco, CA, USA; Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
| |
Collapse
|
6
|
Foreman AL, Warth B, Hessel EVS, Price EJ, Schymanski EL, Cantelli G, Parkinson H, Hecht H, Klánová J, Vlaanderen J, Hilscherova K, Vrijheid M, Vineis P, Araujo R, Barouki R, Vermeulen R, Lanone S, Brunak S, Sebert S, Karjalainen T. Adopting Mechanistic Molecular Biology Approaches in Exposome Research for Causal Understanding. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:7256-7269. [PMID: 38641325 PMCID: PMC11064223 DOI: 10.1021/acs.est.3c07961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/21/2024]
Abstract
Through investigating the combined impact of the environmental exposures experienced by an individual throughout their lifetime, exposome research provides opportunities to understand and mitigate negative health outcomes. While current exposome research is driven by epidemiological studies that identify associations between exposures and effects, new frameworks integrating more substantial population-level metadata, including electronic health and administrative records, will shed further light on characterizing environmental exposure risks. Molecular biology offers methods and concepts to study the biological and health impacts of exposomes in experimental and computational systems. Of particular importance is the growing use of omics readouts in epidemiological and clinical studies. This paper calls for the adoption of mechanistic molecular biology approaches in exposome research as an essential step in understanding the genotype and exposure interactions underlying human phenotypes. A series of recommendations are presented to make the necessary and appropriate steps to move from exposure association to causation, with a huge potential to inform precision medicine and population health. This includes establishing hypothesis-driven laboratory testing within the exposome field, supported by appropriate methods to read across from model systems research to human.
Collapse
Affiliation(s)
- Amy L. Foreman
- European
Molecular Biology Laboratory & European Bioinformatics Institute
(EMBL-EBI), Wellcome Trust Genome Campus, Hinxton CB10 1SD, U.K.
| | - Benedikt Warth
- Department
of Food Chemistry and Toxicology, University
of Vienna, 1090 Vienna, Austria
| | - Ellen V. S. Hessel
- National
Institute for Public Health and the Environment (RIVM), Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
| | - Elliott J. Price
- RECETOX,
Faculty of Science, Masaryk University, Kotlarska 2, Brno 60200, Czech Republic
| | - Emma L. Schymanski
- Luxembourg
Centre for Systems Biomedicine, University
of Luxembourg, 6 avenue
du Swing, L-4367 Belvaux, Luxembourg
| | - Gaia Cantelli
- European
Molecular Biology Laboratory & European Bioinformatics Institute
(EMBL-EBI), Wellcome Trust Genome Campus, Hinxton CB10 1SD, U.K.
| | - Helen Parkinson
- European
Molecular Biology Laboratory & European Bioinformatics Institute
(EMBL-EBI), Wellcome Trust Genome Campus, Hinxton CB10 1SD, U.K.
| | - Helge Hecht
- RECETOX,
Faculty of Science, Masaryk University, Kotlarska 2, Brno 60200, Czech Republic
| | - Jana Klánová
- RECETOX,
Faculty of Science, Masaryk University, Kotlarska 2, Brno 60200, Czech Republic
| | - Jelle Vlaanderen
- Institute
for Risk Assessment Sciences, Division of Environmental Epidemiology, Utrecht University, Heidelberglaan 8 3584 CS Utrecht, The Netherlands
| | - Klara Hilscherova
- RECETOX,
Faculty of Science, Masaryk University, Kotlarska 2, Brno 60200, Czech Republic
| | - Martine Vrijheid
- Institute
for Global Health (ISGlobal), Barcelona
Biomedical Research Park (PRBB), Doctor Aiguader, 88, 08003 Barcelona, Spain
- Universitat
Pompeu Fabra, Carrer
de la Mercè, 12, Ciutat Vella, 08002 Barcelona, Spain
- Centro de Investigación Biomédica en Red
Epidemiología
y Salud Pública (CIBERESP), Av. Monforte de Lemos, 3-5. Pebellón 11, Planta 0, 28029 Madrid, Spain
| | - Paolo Vineis
- Department
of Epidemiology and Biostatistics, School of Public Health, Imperial College, London SW7 2AZ, U.K.
| | - Rita Araujo
- European Commission, DG Research and Innovation, Sq. Frère-Orban 8, 1000 Bruxelles, Belgium
| | | | - Roel Vermeulen
- Institute
for Risk Assessment Sciences, Division of Environmental Epidemiology, Utrecht University, Heidelberglaan 8 3584 CS Utrecht, The Netherlands
| | - Sophie Lanone
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France
| | - Søren Brunak
- Novo
Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Blegdamsvej 3B, 2200 København, Denmark
| | - Sylvain Sebert
- Research
Unit of Population Health, University of
Oulu, P.O. Box 8000, FI-90014 Oulu, Finland
| | - Tuomo Karjalainen
- European Commission, DG Research and Innovation, Sq. Frère-Orban 8, 1000 Bruxelles, Belgium
| |
Collapse
|
7
|
Yang L, Liu F, Hahm H, Okuda T, Li X, Zhang Y, Kalyanaraman V, Heitmeier MR, Samineni VK. Projection-TAGs enable multiplex projection tracing and multi-modal profiling of projection neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.24.590975. [PMID: 38712231 PMCID: PMC11071495 DOI: 10.1101/2024.04.24.590975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Single-cell multiomic techniques have sparked immense interest in developing a comprehensive multi-modal map of diverse neuronal cell types and their brain wide projections. However, investigating the spatial organization, transcriptional and epigenetic landscapes of brain wide projection neurons is hampered by the lack of efficient and easily adoptable tools. Here we introduce Projection-TAGs, a retrograde AAV platform that allows multiplex tagging of projection neurons using RNA barcodes. By using Projection-TAGs, we performed multiplex projection tracing of the mouse cortex and high-throughput single-cell profiling of the transcriptional and epigenetic landscapes of the cortical projection neurons. Projection-TAGs can be leveraged to obtain a snapshot of activity-dependent recruitment of distinct projection neurons and their molecular features in the context of a specific stimulus. Given its flexibility, usability, and compatibility, we envision that Projection-TAGs can be readily applied to build a comprehensive multi-modal map of brain neuronal cell types and their projections.
Collapse
Affiliation(s)
- Lite Yang
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
- Neuroscience Graduate Program, Division of Biology & Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, United States
| | - Fang Liu
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Hannah Hahm
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Takao Okuda
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Xiaoyue Li
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Yufen Zhang
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Vani Kalyanaraman
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Monique R. Heitmeier
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| | - Vijay K. Samineni
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, MO, United States
| |
Collapse
|
8
|
Kosicki M, Cintrón DL, Page NF, Georgakopoulos-Soares I, Akiyama JA, Plajzer-Frick I, Novak CS, Kato M, Hunter RD, von Maydell K, Barton S, Godfrey P, Beckman E, Sanders SJ, Pennacchio LA, Ahituv N. Massively parallel reporter assays and mouse transgenic assays provide complementary information about neuronal enhancer activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590634. [PMID: 38712228 PMCID: PMC11071441 DOI: 10.1101/2024.04.22.590634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Genetic studies find hundreds of thousands of noncoding variants associated with psychiatric disorders. Massively parallel reporter assays (MPRAs) and in vivo transgenic mouse assays can be used to assay the impact of these variants. However, the relevance of MPRAs to in vivo function is unknown and transgenic assays suffer from low throughput. Here, we studied the utility of combining the two assays to study the impact of non-coding variants. We carried out an MPRA on over 50,000 sequences derived from enhancers validated in transgenic mouse assays and from multiple fetal neuronal ATAC-seq datasets. We also tested over 20,000 variants, including synthetic mutations in highly active neuronal enhancers and 177 common variants associated with psychiatric disorders. Variants with a high impact on MPRA activity were further tested in mice. We found a strong and specific correlation between MPRA and mouse neuronal enhancer activity including changes in neuronal enhancer activity in mouse embryos for variants with strong MPRA effects. Mouse assays also revealed pleiotropic variant effects that could not be observed in MPRA. Our work provides a large catalog of functional neuronal enhancers and variant effects and highlights the effectiveness of combining MPRAs and mouse transgenic assays.
Collapse
Affiliation(s)
- Michael Kosicki
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Dianne Laboy Cintrón
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA 94158, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA 94158, USA
| | - Nicholas F. Page
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA 94158, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA 94158, USA
- Department of Psychiatry and Behavioral Sciences, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Ilias Georgakopoulos-Soares
- Institute for Personalized Medicine, Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Jennifer A. Akiyama
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ingrid Plajzer-Frick
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Catherine S. Novak
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Momoe Kato
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Riana D. Hunter
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kianna von Maydell
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Sarah Barton
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Patrick Godfrey
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Erik Beckman
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Stephan J. Sanders
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA 94158, USA
- Department of Psychiatry and Behavioral Sciences, Kavli Institute for Fundamental Neuroscience, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
- Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford, OX3 16 7TY, UK
| | - Len A. Pennacchio
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Nadav Ahituv
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA 94158, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA 94158, USA
| |
Collapse
|
9
|
Sun J, Noss S, Banerjee D, Das M, Girirajan S. Strategies for dissecting the complexity of neurodevelopmental disorders. Trends Genet 2024; 40:187-202. [PMID: 37949722 PMCID: PMC10872993 DOI: 10.1016/j.tig.2023.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 09/20/2023] [Accepted: 10/16/2023] [Indexed: 11/12/2023]
Abstract
Neurodevelopmental disorders (NDDs) are associated with a wide range of clinical features, affecting multiple pathways involved in brain development and function. Recent advances in high-throughput sequencing have unveiled numerous genetic variants associated with NDDs, which further contribute to disease complexity and make it challenging to infer disease causation and underlying mechanisms. Herein, we review current strategies for dissecting the complexity of NDDs using model organisms, induced pluripotent stem cells, single-cell sequencing technologies, and massively parallel reporter assays. We further highlight single-cell CRISPR-based screening techniques that allow genomic investigation of cellular transcriptomes with high efficiency, accuracy, and throughput. Overall, we provide an integrated review of experimental approaches that can be applicable for investigating a broad range of complex disorders.
Collapse
Affiliation(s)
- Jiawan Sun
- Molecular, Cellular, and Integrative Biosciences Graduate Program, The Huck Institutes of Life Sciences, University Park, PA 16802, USA
| | - Serena Noss
- Molecular, Cellular, and Integrative Biosciences Graduate Program, The Huck Institutes of Life Sciences, University Park, PA 16802, USA
| | - Deepro Banerjee
- Bioinformatics and Genomics Graduate Program, The Huck Institutes of Life Sciences, University Park, PA 16802, USA
| | - Maitreya Das
- Molecular, Cellular, and Integrative Biosciences Graduate Program, The Huck Institutes of Life Sciences, University Park, PA 16802, USA
| | - Santhosh Girirajan
- Molecular, Cellular, and Integrative Biosciences Graduate Program, The Huck Institutes of Life Sciences, University Park, PA 16802, USA; Bioinformatics and Genomics Graduate Program, The Huck Institutes of Life Sciences, University Park, PA 16802, USA; Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA; Department of Anthropology, Pennsylvania State University, University Park, PA 16802, USA.
| |
Collapse
|
10
|
Coughlin GM, Borsos M, Appling N, Barcelona BH, Mayfield AMH, Mackey ED, Eser RA, Chen X, Kumar SR, Gradinaru V. Spatial genomics of AAVs reveals mechanism of transcriptional crosstalk that enables targeted delivery of large genetic cargo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.23.573214. [PMID: 38187707 PMCID: PMC10769433 DOI: 10.1101/2023.12.23.573214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Integrating cell type-specific regulatory elements (e.g. enhancers) with recombinant adeno-associated viruses (AAVs) can provide broad and efficient genetic access to specific cell types. However, the packaging capacity of AAVs restricts the size of both the enhancers and the cargo that can be delivered. Transcriptional crosstalk offers a novel paradigm for cell type-specific expression of large cargo, by separating distally-acting regulatory elements into a second AAV genome. Here, we identify and profile transcriptional crosstalk in AAV genomes carrying 11 different enhancers active in mouse brain. To understand transcriptional crosstalk, we develop spatial genomics methods to identify and localize AAV genomes and their concatemeric forms in cultured cells and in tissue. Using these methods, we construct detailed views of the dynamics of AAV transduction and demonstrate that transcriptional crosstalk is dependent upon concatemer formation. Finally, we leverage transcriptional crosstalk to drive expression of a large Cas9 cargo in a cell type-specific manner with systemically-administered engineered AAVs and demonstrate AAV-delivered, minimally-invasive, cell type-specific gene editing in wildtype animals that recapitulates known disease phenotypes.
Collapse
Affiliation(s)
- Gerard M. Coughlin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Máté Borsos
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Nathan Appling
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Bre’Anna H. Barcelona
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Acacia M. H. Mayfield
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Elisha D. Mackey
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Rana A. Eser
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Xinhong Chen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Sripriya Ravindra Kumar
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - Viviana Gradinaru
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| |
Collapse
|
11
|
Zhao J, Baltoumas FA, Konnaris MA, Mouratidis I, Liu Z, Sims J, Agarwal V, Pavlopoulos GA, Georgakopoulos-Soares I, Ahituv N. MPRAbase: A Massively Parallel Reporter Assay Database. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.19.567742. [PMID: 38045264 PMCID: PMC10690217 DOI: 10.1101/2023.11.19.567742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Massively parallel reporter assays (MPRAs) represent a set of high-throughput technologies that measure the functional effects of thousands of sequences/variants on gene regulatory activity. There are several different variations of MPRA technology and they are used for numerous applications, including regulatory element discovery, variant effect measurement, saturation mutagenesis, synthetic regulatory element generation or characterization of evolutionary gene regulatory differences. Despite their many designs and uses, there is no comprehensive database that incorporates the results of these experiments. To address this, we developed MPRAbase, a manually curated database that currently harbors 129 experiments, encompassing 17,718,677 elements tested across 35 cell types and 4 organisms. The MPRAbase web interface ( http://www.mprabase.com ) serves as a centralized user-friendly repository to download existing MPRA data for independent analysis and is designed with the ability to allow researchers to share their published data for rapid dissemination to the community.
Collapse
|
12
|
Armendariz DA, Sundarrajan A, Hon GC. Breaking enhancers to gain insights into developmental defects. eLife 2023; 12:e88187. [PMID: 37497775 PMCID: PMC10374278 DOI: 10.7554/elife.88187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 07/19/2023] [Indexed: 07/28/2023] Open
Abstract
Despite ground-breaking genetic studies that have identified thousands of risk variants for developmental diseases, how these variants lead to molecular and cellular phenotypes remains a gap in knowledge. Many of these variants are non-coding and occur at enhancers, which orchestrate key regulatory programs during development. The prevailing paradigm is that non-coding variants alter the activity of enhancers, impacting gene expression programs, and ultimately contributing to disease risk. A key obstacle to progress is the systematic functional characterization of non-coding variants at scale, especially since enhancer activity is highly specific to cell type and developmental stage. Here, we review the foundational studies of enhancers in developmental disease and current genomic approaches to functionally characterize developmental enhancers and their variants at scale. In the coming decade, we anticipate systematic enhancer perturbation studies to link non-coding variants to molecular mechanisms, changes in cell state, and disease phenotypes.
Collapse
Affiliation(s)
- Daniel A Armendariz
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
| | - Anjana Sundarrajan
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
| | - Gary C Hon
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, United States
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, United States
- Lyda Hill Department of Bioinformatics, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, United States
| |
Collapse
|
13
|
Chan YC, Kienle E, Oti M, Di Liddo A, Mendez-Lago M, Aschauer DF, Peter M, Pagani M, Arnold C, Vonderheit A, Schön C, Kreuz S, Stark A, Rumpel S. An unbiased AAV-STARR-seq screen revealing the enhancer activity map of genomic regions in the mouse brain in vivo. Sci Rep 2023; 13:6745. [PMID: 37185990 PMCID: PMC10130037 DOI: 10.1038/s41598-023-33448-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 04/12/2023] [Indexed: 05/17/2023] Open
Abstract
Enhancers are important cis-regulatory elements controlling cell-type specific expression patterns of genes. Furthermore, combinations of enhancers and minimal promoters are utilized to construct small, artificial promoters for gene delivery vectors. Large-scale functional screening methodology to construct genomic maps of enhancer activities has been successfully established in cultured cell lines, however, not yet applied to terminally differentiated cells and tissues in a living animal. Here, we transposed the Self-Transcribing Active Regulatory Region Sequencing (STARR-seq) technique to the mouse brain using adeno-associated-viruses (AAV) for the delivery of a highly complex screening library tiling entire genomic regions and covering in total 3 Mb of the mouse genome. We identified 483 sequences with enhancer activity, including sequences that were not predicted by DNA accessibility or histone marks. Characterizing the expression patterns of fluorescent reporters controlled by nine candidate sequences, we observed differential expression patterns also in sparse cell types. Together, our study provides an entry point for the unbiased study of enhancer activities in organisms during health and disease.
Collapse
Affiliation(s)
- Ya-Chien Chan
- Institute of Physiology, Focus Program Translational Neurosciences, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Eike Kienle
- Institute of Physiology, Focus Program Translational Neurosciences, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Martin Oti
- Institute of Molecular Biology GmbH (IMB), Mainz, Germany
- Global Computational Biology and Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an Der Riß, Germany
| | | | | | - Dominik F Aschauer
- Institute of Physiology, Focus Program Translational Neurosciences, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Manuel Peter
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Michaela Pagani
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Cosmas Arnold
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- CeMM Research Center for Molecular Medicine, Austrian Academy of Sciences, Vienna, Austria
| | | | - Christian Schön
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an Der Riß, Germany
| | - Sebastian Kreuz
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an Der Riß, Germany
| | - Alexander Stark
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
- Medical University of Vienna, Vienna BioCenter (VBC), 1030, Vienna, Austria
| | - Simon Rumpel
- Institute of Physiology, Focus Program Translational Neurosciences, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany.
| |
Collapse
|
14
|
Das M, Hossain A, Banerjee D, Praul CA, Girirajan S. Challenges and considerations for reproducibility of STARR-seq assays. Genome Res 2023; 33:479-495. [PMID: 37130797 PMCID: PMC10234304 DOI: 10.1101/gr.277204.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 03/15/2023] [Indexed: 05/04/2023]
Abstract
High-throughput methods such as RNA-seq, ChIP-seq, and ATAC-seq have well-established guidelines, commercial kits, and analysis pipelines that enable consistency and wider adoption for understanding genome function and regulation. STARR-seq, a popular assay for directly quantifying the activities of thousands of enhancer sequences simultaneously, has seen limited standardization across studies. The assay is long, with more than 250 steps, and frequent customization of the protocol and variations in bioinformatics methods raise concerns for reproducibility of STARR-seq studies. Here, we assess each step of the protocol and analysis pipelines from published sources and in-house assays, and identify critical steps and quality control (QC) checkpoints necessary for reproducibility of the assay. We also provide guidelines for experimental design, protocol scaling, customization, and analysis pipelines for better adoption of the assay. These resources will allow better optimization of STARR-seq for specific research needs, enable comparisons and integration across studies, and improve the reproducibility of results.
Collapse
Affiliation(s)
- Maitreya Das
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA;
- Molecular and Cellular Integrative Biosciences Graduate Program, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Ayaan Hossain
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Bioinformatics and Genomics Graduate Program, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Deepro Banerjee
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Bioinformatics and Genomics Graduate Program, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Craig Alan Praul
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Santhosh Girirajan
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA;
- Molecular and Cellular Integrative Biosciences Graduate Program, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Bioinformatics and Genomics Graduate Program, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| |
Collapse
|
15
|
Zheng Y, VanDusen NJ. Massively Parallel Reporter Assays for High-Throughput In Vivo Analysis of Cis-Regulatory Elements. J Cardiovasc Dev Dis 2023; 10:jcdd10040144. [PMID: 37103023 PMCID: PMC10146671 DOI: 10.3390/jcdd10040144] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023] Open
Abstract
The rapid improvement of descriptive genomic technologies has fueled a dramatic increase in hypothesized connections between cardiovascular gene expression and phenotypes. However, in vivo testing of these hypotheses has predominantly been relegated to slow, expensive, and linear generation of genetically modified mice. In the study of genomic cis-regulatory elements, generation of mice featuring transgenic reporters or cis-regulatory element knockout remains the standard approach. While the data obtained is of high quality, the approach is insufficient to keep pace with candidate identification and therefore results in biases introduced during the selection of candidates for validation. However, recent advances across a range of disciplines are converging to enable functional genomic assays that can be conducted in a high-throughput manner. Here, we review one such method, massively parallel reporter assays (MPRAs), in which the activities of thousands of candidate genomic regulatory elements are simultaneously assessed via the next-generation sequencing of a barcoded reporter transcript. We discuss best practices for MPRA design and use, with a focus on practical considerations, and review how this emerging technology has been successfully deployed in vivo. Finally, we discuss how MPRAs are likely to evolve and be used in future cardiovascular research.
Collapse
|
16
|
Gallego Romero I, Lea AJ. Leveraging massively parallel reporter assays for evolutionary questions. Genome Biol 2023; 24:26. [PMID: 36788564 PMCID: PMC9926830 DOI: 10.1186/s13059-023-02856-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 01/17/2023] [Indexed: 02/16/2023] Open
Abstract
A long-standing goal of evolutionary biology is to decode how gene regulation contributes to organismal diversity. Doing so is challenging because it is hard to predict function from non-coding sequence and to perform molecular research with non-model taxa. Massively parallel reporter assays (MPRAs) enable the testing of thousands to millions of sequences for regulatory activity simultaneously. Here, we discuss the execution, advantages, and limitations of MPRAs, with a focus on evolutionary questions. We propose solutions for extending MPRAs to rare taxa and those with limited genomic resources, and we underscore MPRA's broad potential for driving genome-scale, functional studies across organisms.
Collapse
Affiliation(s)
- Irene Gallego Romero
- Melbourne Integrative Genomics, University of Melbourne, Royal Parade, Parkville, Victoria, 3010, Australia. .,School of BioSciences, The University of Melbourne, Royal Parade, Parkville, 3010, Australia. .,The Centre for Stem Cell Systems, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, 30 Royal Parade, Parkville, Victoria, 3010, Australia. .,Center for Genomics, Evolution and Medicine, Institute of Genomics, University of Tartu, Riia 23b, 51010, Tartu, Estonia.
| | - Amanda J. Lea
- grid.152326.10000 0001 2264 7217Department of Biological Sciences, Vanderbilt University, Nashville, TN 37240 USA ,grid.152326.10000 0001 2264 7217Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN 37240 USA ,grid.152326.10000 0001 2264 7217Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN 37240 USA ,Child and Brain Development Program, Canadian Institute for Advanced Study, Toronto, Canada
| |
Collapse
|
17
|
Cooper YA, Guo Q, Geschwind DH. Multiplexed functional genomic assays to decipher the noncoding genome. Hum Mol Genet 2022; 31:R84-R96. [PMID: 36057282 PMCID: PMC9585676 DOI: 10.1093/hmg/ddac194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/14/2022] Open
Abstract
Linkage disequilibrium and the incomplete regulatory annotation of the noncoding genome complicates the identification of functional noncoding genetic variants and their causal association with disease. Current computational methods for variant prioritization have limited predictive value, necessitating the application of highly parallelized experimental assays to efficiently identify functional noncoding variation. Here, we summarize two distinct approaches, massively parallel reporter assays and CRISPR-based pooled screens and describe their flexible implementation to characterize human noncoding genetic variation at unprecedented scale. Each approach provides unique advantages and limitations, highlighting the importance of multimodal methodological integration. These multiplexed assays of variant effects are undoubtedly poised to play a key role in the experimental characterization of noncoding genetic risk, informing our understanding of the underlying mechanisms of disease-associated loci and the development of more robust predictive classification algorithms.
Collapse
Affiliation(s)
- Yonatan A Cooper
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Medical Scientist Training Program, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA, USA
| | - Qiuyu Guo
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA, USA
| | - Daniel H Geschwind
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Program in Neurogenetics, Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA
- Center for Autism Research and Treatment, Semel Institute, University of California Los Angeles, Los Angeles, CA, USA
- Institute of Precision Health, University of California Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
18
|
Giacoman-Lozano M, Meléndez-Ramírez C, Martinez-Ledesma E, Cuevas-Diaz Duran R, Velasco I. Epigenetics of neural differentiation: Spotlight on enhancers. Front Cell Dev Biol 2022; 10:1001701. [PMID: 36313573 PMCID: PMC9606577 DOI: 10.3389/fcell.2022.1001701] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 10/03/2022] [Indexed: 11/28/2022] Open
Abstract
Neural induction, both in vivo and in vitro, includes cellular and molecular changes that result in phenotypic specialization related to specific transcriptional patterns. These changes are achieved through the implementation of complex gene regulatory networks. Furthermore, these regulatory networks are influenced by epigenetic mechanisms that drive cell heterogeneity and cell-type specificity, in a controlled and complex manner. Epigenetic marks, such as DNA methylation and histone residue modifications, are highly dynamic and stage-specific during neurogenesis. Genome-wide assessment of these modifications has allowed the identification of distinct non-coding regulatory regions involved in neural cell differentiation, maturation, and plasticity. Enhancers are short DNA regulatory regions that bind transcription factors (TFs) and interact with gene promoters to increase transcriptional activity. They are of special interest in neuroscience because they are enriched in neurons and underlie the cell-type-specificity and dynamic gene expression profiles. Classification of the full epigenomic landscape of neural subtypes is important to better understand gene regulation in brain health and during diseases. Advances in novel next-generation high-throughput sequencing technologies, genome editing, Genome-wide association studies (GWAS), stem cell differentiation, and brain organoids are allowing researchers to study brain development and neurodegenerative diseases with an unprecedented resolution. Herein, we describe important epigenetic mechanisms related to neurogenesis in mammals. We focus on the potential roles of neural enhancers in neurogenesis, cell-fate commitment, and neuronal plasticity. We review recent findings on epigenetic regulatory mechanisms involved in neurogenesis and discuss how sequence variations within enhancers may be associated with genetic risk for neurological and psychiatric disorders.
Collapse
Affiliation(s)
- Mayela Giacoman-Lozano
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, NL, Mexico
| | - César Meléndez-Ramírez
- Instituto de Fisiología Celular—Neurociencias, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
- Laboratorio de Reprogramación Celular, Instituto Nacional de Neurología y Neurocirugía “Manuel Velasco Suárez”, Mexico City, Mexico
| | - Emmanuel Martinez-Ledesma
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, NL, Mexico
- Tecnologico de Monterrey, The Institute for Obesity Research, Monterrey, NL, Mexico
| | - Raquel Cuevas-Diaz Duran
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, NL, Mexico
- *Correspondence: Raquel Cuevas-Diaz Duran, ; Iván Velasco,
| | - Iván Velasco
- Instituto de Fisiología Celular—Neurociencias, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
- Laboratorio de Reprogramación Celular, Instituto Nacional de Neurología y Neurocirugía “Manuel Velasco Suárez”, Mexico City, Mexico
- *Correspondence: Raquel Cuevas-Diaz Duran, ; Iván Velasco,
| |
Collapse
|
19
|
Pouchelon G, Vergara J, McMahon J, Gorissen BL, Lin JD, Vormstein-Schneider D, Niehaus JL, Burbridge TJ, Wester JC, Sherer M, Fernandez-Otero M, Allaway KC, Pelkey K, Chittajallu R, McBain CJ, Fan M, Nasse JS, Wildenberg GA, Fishell G, Dimidschstein J. A versatile viral toolkit for functional discovery in the nervous system. CELL REPORTS METHODS 2022; 2:100225. [PMID: 35784651 PMCID: PMC9243523 DOI: 10.1016/j.crmeth.2022.100225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 03/21/2022] [Accepted: 05/04/2022] [Indexed: 12/24/2022]
Abstract
The ability to precisely control transgene expression is essential for basic research and clinical applications. Adeno-associated viruses (AAVs) are non-pathogenic and can be used to drive stable expression in virtually any tissue, cell type, or species, but their limited genomic payload results in a trade-off between the transgenes that can be incorporated and the complexity of the regulatory elements controlling their expression. Resolving these competing imperatives in complex experiments inevitably results in compromises. Here, we assemble an optimized viral toolkit (VTK) that addresses these limitations and allows for efficient combinatorial targeting of cell types. Moreover, their modular design explicitly enables further refinements. We achieve this in compact vectors by integrating structural improvements of AAV vectors with innovative molecular tools. We illustrate the potential of this approach through a systematic demonstration of their utility for targeting cell types and querying their biology using a wide array of genetically encoded tools.
Collapse
Affiliation(s)
- Gabrielle Pouchelon
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | - Josselyn Vergara
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
| | - Justin McMahon
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
| | - Bram L. Gorissen
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | - Jessica D. Lin
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
| | | | | | - Timothy J. Burbridge
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | - Jason C. Wester
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA
| | - Mia Sherer
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | - Marian Fernandez-Otero
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | - Kathryn C. Allaway
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | - Kenneth Pelkey
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA
| | - Ramesh Chittajallu
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA
| | - Chris J. McBain
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA
| | | | | | - Gregg A. Wildenberg
- Department of Neurobiology, University of Chicago, Chicago, IL 60637, USA
- Biosciences Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Gordon Fishell
- Broad Institute, Stanley Center for Psychiatric Research, Cambridge, MA 02142, USA
- Harvard Medical School, Blavatnik Institute, Neurobiology, Boston, MA 02115, USA
| | | |
Collapse
|
20
|
Warren TL, Lambert JT, Nord AS. AAV Deployment of Enhancer-Based Expression Constructs In Vivo in Mouse Brain. J Vis Exp 2022:10.3791/62650. [PMID: 35435902 PMCID: PMC10010840 DOI: 10.3791/62650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Enhancers are binding platforms for a diverse array of transcription factors that drive specific expression patterns of tissue- and cell-type-specific genes. Multiple means of assessing non-coding DNA and various chromatin states have proven useful in predicting the presence of enhancer sequences in the genome, but validating the activity of these sequences and finding the organs and developmental stages they are active in is a labor-intensive process. Recent advances in adeno-associated virus (AAV) vectors have enabled the widespread delivery of transgenes to mouse tissues, enabling in vivo enhancer testing without necessitating a transgenic animal. This protocol shows how a reporter construct that expresses EGFP under the control of a minimal promoter, which does not drive significant expression on its own, can be used to study the activity patterns of candidate enhancer sequences in the mouse brain. An AAV-packaged reporter construct is delivered to the mouse brain and incubated for 1-4 weeks, after which the animal is sacrificed, and brain sections are observed under a microscope. EGFP appears in cells in which the tested enhancer is sufficient to initiate gene expression, pinpointing the location and developmental stage in which the enhancer is active in the brain. Standard cloning methods, low-cost AAV packaging, and expanding AAV serotypes and methods for in vivo delivery and standard imaging readout make this an accessible approach for the study of how gene expression is regulated in the brain.
Collapse
Affiliation(s)
- Tracy L Warren
- Department of Psychiatry and Behavioral Sciences, University of California, Davis; Department of Neurobiology, Physiology and Behavior, University of California, Davis
| | - Jason T Lambert
- Department of Psychiatry and Behavioral Sciences, University of California, Davis; Department of Neurobiology, Physiology and Behavior, University of California, Davis;
| | - Alex S Nord
- Department of Psychiatry and Behavioral Sciences, University of California, Davis; Department of Neurobiology, Physiology and Behavior, University of California, Davis;
| |
Collapse
|
21
|
Lambert JT, Su-Feher L, Cichewicz K, Warren TL, Zdilar I, Wang Y, Lim KJ, Haigh JL, Morse SJ, Canales CP, Stradleigh TW, Castillo Palacios E, Haghani V, Moss SD, Parolini H, Quintero D, Shrestha D, Vogt D, Byrne LC, Nord AS. Parallel functional testing identifies enhancers active in early postnatal mouse brain. eLife 2021; 10:69479. [PMID: 34605404 PMCID: PMC8577842 DOI: 10.7554/elife.69479] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 10/02/2021] [Indexed: 01/07/2023] Open
Abstract
Enhancers are cis-regulatory elements that play critical regulatory roles in modulating developmental transcription programs and driving cell-type-specific and context-dependent gene expression in the brain. The development of massively parallel reporter assays (MPRAs) has enabled high-throughput functional screening of candidate DNA sequences for enhancer activity. Tissue-specific screening of in vivo enhancer function at scale has the potential to greatly expand our understanding of the role of non-coding sequences in development, evolution, and disease. Here, we adapted a self-transcribing regulatory element MPRA strategy for delivery to early postnatal mouse brain via recombinant adeno-associated virus (rAAV). We identified and validated putative enhancers capable of driving reporter gene expression in mouse forebrain, including regulatory elements within an intronic CACNA1C linkage disequilibrium block associated with risk in neuropsychiatric disorder genetic studies. Paired screening and single enhancer in vivo functional testing, as we show here, represents a powerful approach towards characterizing regulatory activity of enhancers and understanding how enhancer sequences organize gene expression in the brain.
Collapse
Affiliation(s)
- Jason T Lambert
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Linda Su-Feher
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Karol Cichewicz
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Tracy L Warren
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Iva Zdilar
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Yurong Wang
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Kenneth J Lim
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Jessica L Haigh
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Sarah J Morse
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Cesar P Canales
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Tyler W Stradleigh
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Erika Castillo Palacios
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Viktoria Haghani
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Spencer D Moss
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Hannah Parolini
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Diana Quintero
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Diwash Shrestha
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Daniel Vogt
- Department of Pediatrics and Human Development, Grand Rapids Research Center, Michigan State UniversityGrand RapidsUnited States
| | - Leah C Byrne
- Helen Wills Neuroscience Institute, University of California, BerkeleyBerkeleyUnited States,Departments of Ophthalmology and Neurobiology, University of PittsburghPittsburghUnited States
| | - Alex S Nord
- Department of Psychiatry and Behavioral Sciences, University of California, DavisDavisUnited States,Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| |
Collapse
|