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Medlock-Lanier T, Clay KB, Roberts-Galbraith RH. Planarian LDB and SSDP proteins scaffold transcriptional complexes for regeneration and patterning. Dev Biol 2024; 515:67-78. [PMID: 38968988 PMCID: PMC11361279 DOI: 10.1016/j.ydbio.2024.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/27/2024] [Accepted: 06/28/2024] [Indexed: 07/07/2024]
Abstract
Sequence-specific transcription factors often function as components of large regulatory complexes. LIM-domain binding protein (LDB) and single-stranded DNA-binding protein (SSDP) function as core scaffolds of transcriptional complexes in animals and plants. Little is known about potential partners and functions for LDB/SSDP complexes in the context of tissue regeneration. In this work, we find that planarian LDB1 and SSDP2 promote tissue regeneration, with a particular function in anterior regeneration and mediolateral polarity reestablishment. We find that LDB1 and SSDP2 interact with one another and with characterized planarian LIM-HD proteins Arrowhead, Islet1, and Lhx1/5-1. We also show that SSDP2 and LDB1 function with islet1 in polarity reestablishment and with lhx1/5-1 in serotonergic neuron maturation. Finally, we find new roles for LDB1 and SSDP2 in regulating gene expression in the planarian intestine and parenchyma; these functions are likely LIM-HD-independent. Together, our work provides insight into LDB/SSDP complexes in a highly regenerative organism. Further, our work provides a strong starting point for identifying and characterizing potential binding partners of LDB1 and SSDP2 and for exploring roles for these proteins in diverse aspects of planarian physiology.
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Affiliation(s)
| | - Kendall B Clay
- Neuroscience Program, University of Georgia, Athens, GA, USA
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2
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Pathak GA, Pietrzak RH, Lacobelle A, Overstreet C, Wendt FR, Deak JD, Friligkou E, Nunez Y, Montalvo-Ortiz JL, Levey DF, Kranzler HR, Gelernter J, Polimanti R. Epigenetic and Genetic Profiling of Comorbidity Patterns among Substance Dependence Diagnoses. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.10.08.24315111. [PMID: 39417130 PMCID: PMC11482987 DOI: 10.1101/2024.10.08.24315111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2024]
Abstract
Objective This study investigated the genetic and epigenetic mechanisms underlying the comorbidity patterns of five substance dependence diagnoses (SDs; alcohol, AD; cannabis, CaD; cocaine, CoD; opioid, OD; tobacco, TD). Methods A latent class analysis (LCA) was performed on 31,197 individuals (average age 42±11 years; 49% females) from six cohorts to identify comorbid DSM-IV SD patterns. In subsets of this sample, we tested SD-latent classes with respect to polygenic burden of psychiatric and behavioral traits and epigenome-wide changes in three population groups. Results An LCA identified four latent classes related to SD comorbidities: AD+TD, CoD+TD, AD+CoD+OD+TD (i.e., polysubstance use, PSU), and TD. In the epigenome-wide association analysis, SPATA4 cg02833127 was associated with CoD+TD, AD+TD, and PSU latent classes. AD+TD latent class was also associated with CpG sites located on ARID1B , NOTCH1 , SERTAD4, and SIN3B , while additional epigenome-wide significant associations with CoD+TD latent class were observed in ANO6 and MOV10 genes. PSU-latent class was also associated with a differentially methylated region in LDB1 . We also observed shared polygenic score (PGS) associations for PSU, AD+TD, and CoD+TD latent classes (i.e., attention-deficit hyperactivity disorder, anxiety, educational attainment, and schizophrenia PGS). In contrast, TD-latent class was exclusively associated with posttraumatic stress disorder-PGS. Other specific associations were observed for PSU-latent class (subjective wellbeing-PGS and neuroticism-PGS) and AD+TD-latent class (bipolar disorder-PGS). Conclusions We identified shared and unique genetic and epigenetic mechanisms underlying SD comorbidity patterns. These findings highlight the importance of modeling the co-occurrence of SD diagnoses when investigating the molecular basis of addiction-related traits.
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3
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Prud'homme B. The power of proximity: mechanisms and biological roles of transvection. Curr Opin Genet Dev 2024; 89:102269. [PMID: 39368316 DOI: 10.1016/j.gde.2024.102269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2024] [Revised: 09/10/2024] [Accepted: 09/16/2024] [Indexed: 10/07/2024]
Abstract
The phenomenon of transvection, defined as a proximity-dependent interallelic interaction, has been observed in the context of complementation between mutant alleles for numerous Drosophila genes. Cases of transvection-like phenomena have also been observed in other species, including mammals. However, the potential contribution of transvection to wild-type gene regulation and the underlying mechanisms remain uncertain. Here, I review recent evidence demonstrating the relevance of transvection in physiological contexts. These findings suggest that transvection represents an additional layer of gene regulation that allows cells to fine-tune gene expression based on the proximity of homologous alleles. In addition, recent studies have measured the physical distance between interacting alleles, revealing unexpectedly large and variable distances. I will discuss how these distances are compatible with the 'hub' model of transcriptional regulation.
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Affiliation(s)
- Benjamin Prud'homme
- Aix-Marseille Université, CNRS, IBDM, Institut de Biologie du Développement de Marseille, Campus de Luminy Case 907, Cedex 9, 13288 Marseille, France.
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4
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Solovei I, Mirny L. Spandrels of the cell nucleus. Curr Opin Cell Biol 2024; 90:102421. [PMID: 39180905 DOI: 10.1016/j.ceb.2024.102421] [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: 06/08/2024] [Revised: 07/18/2024] [Accepted: 08/02/2024] [Indexed: 08/27/2024]
Abstract
S.J. Gould and R. Lewontin in their famous "Spandrels paper" (1979) argued that many anatomical elements arise in evolution not due to their "current utility" but rather due to other "reasons for origin", such as other developmental processes, physical constraints and mechanical forces. Here, in the same spirit, we argue that a variety of molecular processes, physical constraints, and mechanical forces, alone or together, generate structures that are detectable in the cell nucleus, yet these structures themselves may not carry any specific function, being a mere reflection of processes that produced them.
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Affiliation(s)
- Irina Solovei
- Biocenter, Ludwig Maximilians University Munich, Planegg-Martinsried, Germany.
| | - Leonid Mirny
- Institute for Medical Engineering and Science, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
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5
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Pedrotti S, Castiglioni I, Perez-Estrada C, Zhao L, Chen JP, Crosetto N, Bienko M. Emerging methods and applications in 3D genomics. Curr Opin Cell Biol 2024; 90:102409. [PMID: 39178735 DOI: 10.1016/j.ceb.2024.102409] [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: 05/13/2024] [Revised: 07/21/2024] [Accepted: 07/22/2024] [Indexed: 08/26/2024]
Abstract
Since the advent of Hi-C in 2009, a plethora of high-throughput sequencing methods have emerged to profile the three-dimensional (3D) organization of eukaryotic genomes, igniting the era of 3D genomics. In recent years, the genomic resolution achievable by these approaches has dramatically increased and several single-cell versions of Hi-C have been developed. Moreover, a new repertoire of tools not based on proximity ligation of digested chromatin has emerged, enabling the investigation of the higher-order organization of chromatin in the nucleus. In this review, we summarize the expanding portfolio of 3D genomic technologies, highlighting recent developments and applications from the past three years. Lastly, we present an outlook of where this technology-driven field might be headed.
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Affiliation(s)
- Simona Pedrotti
- Human Technopole, Viale Rita Levi-Montalcini 1, 20157, Milan, Italy
| | | | - Cynthia Perez-Estrada
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden; Science for Life Laboratory, Solna, 17165, Sweden
| | - Linxuan Zhao
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden; Science for Life Laboratory, Solna, 17165, Sweden
| | - Jinxin Phaedo Chen
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden; Science for Life Laboratory, Solna, 17165, Sweden
| | - Nicola Crosetto
- Human Technopole, Viale Rita Levi-Montalcini 1, 20157, Milan, Italy; Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden; Science for Life Laboratory, Solna, 17165, Sweden.
| | - Magda Bienko
- Human Technopole, Viale Rita Levi-Montalcini 1, 20157, Milan, Italy; Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden; Science for Life Laboratory, Solna, 17165, Sweden.
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6
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Yang J, Shi P, Li Y, Zuo Y, Nie Y, Xu T, Peng D, An Z, Huang T, Zhang J, Zhang W, Xu Y, Tang Z, Li A, Xu J. Regulatory mechanisms orchestrating cellular diversity of Cd36+ olfactory sensory neurons revealed by scRNA-seq and scATAC-seq analysis. Cell Rep 2024; 43:114671. [PMID: 39215999 DOI: 10.1016/j.celrep.2024.114671] [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: 10/31/2023] [Revised: 04/12/2024] [Accepted: 08/07/2024] [Indexed: 09/04/2024] Open
Abstract
Recent discoveries have revealed remarkable complexity within olfactory sensory neurons (OSNs), including the existence of two OSN populations based on the expression of Cd36. However, the regulatory mechanisms governing this cellular diversity in the same cell type remain elusive. Here, we show the preferential expression of 79 olfactory receptors in Cd36+ OSNs and the anterior projection characteristics of Cd36+ OSNs, indicating the non-randomness of Cd36 expression. The integrated analysis of single-cell RNA sequencing (scRNA-seq) and scATAC-seq reveals that the differences in Cd36+/- OSNs occur at the immature OSN stage, with Mef2a and Hdac9 being important regulators of developmental divergence. We hypothesize that the absence of Hdac9 may affect the activation of Mef2a, leading to the up-regulation of Mef2a target genes, including teashirt zinc finger family member 1 (Tshz1), in the Cd36+ OSN lineage. We validate that Tshz1 directly promotes Cd36 expression through enhancer bindings. Our study unravels the intricate regulatory landscape and principles governing cellular diversity in the olfactory system.
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Affiliation(s)
- Jiawen Yang
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Peiyu Shi
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yiheng Li
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yachao Zuo
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yage Nie
- Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China
| | - Tao Xu
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Dongjie Peng
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Ziyang An
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Tingting Huang
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jingyi Zhang
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Weixing Zhang
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yicong Xu
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zhongjie Tang
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Anan Li
- Jiangsu Key Laboratory of Brain Disease and Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China
| | - Jin Xu
- State Key Laboratory of Biocontrol, Innovation Center for Evolutionary Synthetic Biology, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
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Jha A, Hristov B, Wang X, Wang S, Greenleaf WJ, Kundaje A, Aiden EL, Bertero A, Noble WS. Prediction and functional interpretation of inter-chromosomal genome architecture from DNA sequence with TwinC. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.16.613355. [PMID: 39345598 PMCID: PMC11429679 DOI: 10.1101/2024.09.16.613355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/01/2024]
Abstract
Three-dimensional nuclear DNA architecture comprises well-studied intra-chromosomal (cis) folding and less characterized inter-chromosomal (trans) interfaces. Current predictive models of 3D genome folding can effectively infer pairwise cis-chromatin interactions from the primary DNA sequence but generally ignore trans contacts. There is an unmet need for robust models of trans-genome organization that provide insights into their underlying principles and functional relevance. We present TwinC, an interpretable convolutional neural network model that reliably predicts trans contacts measurable through genome-wide chromatin conformation capture (Hi-C). TwinC uses a paired sequence design from replicate Hi-C experiments to learn single base pair relevance in trans interactions across two stretches of DNA. The method achieves high predictive accuracy (AUROC=0.80) on a cross-chromosomal test set from Hi-C experiments in heart tissue. Mechanistically, the neural network learns the importance of compartments, chromatin accessibility, clustered transcription factor binding and G-quadruplexes in forming trans contacts. In summary, TwinC models and interprets trans genome architecture, shedding light on this poorly understood aspect of gene regulation.
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Affiliation(s)
- Anupama Jha
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Borislav Hristov
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Xiao Wang
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
- Paul G. Allen Center for Computer Science & Engineering, University of Washington, Seattle, WA, USA
| | - Sheng Wang
- Paul G. Allen Center for Computer Science & Engineering, University of Washington, Seattle, WA, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, CA, USA
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Anshul Kundaje
- Department of Genetics, Stanford University, Stanford, CA, USA
- Department of Computer Science, Stanford University Stanford, CA, USA
| | - Erez Lieberman Aiden
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Center for Theoretical Biological Physics, Rice University, Houston, TX, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Computer Science, Rice University, Houston, TX, USA
- Department of Computational and Applied Mathematics, Rice University, Houston, TX, USA
| | - Alessandro Bertero
- Molecular Biotechnology Center "Guido Tarone," Department of Molecular Biotechnology and Health Sciences, University of Turin, Torino, Italy
| | - William Stafford Noble
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
- Paul G. Allen Center for Computer Science & Engineering, University of Washington, Seattle, WA, USA
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8
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Taghbalout A, Tung CH, Clow PA, Wang P, Tjong H, Wong CH, Mao DD, Maurya R, Huang MF, Ngan CY, Kim AH, Wei CL. Extrachromosomal DNA Associates with Nuclear Condensates and Reorganizes Chromatin Structures to Enhance Oncogenic Transcription. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.17.613488. [PMID: 39345460 PMCID: PMC11429754 DOI: 10.1101/2024.09.17.613488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/01/2024]
Abstract
Extrachromosomal, circular DNA (ecDNA) is a prevalent oncogenic alteration in cancer genomes, often associated with aggressive tumor behavior and poor patient outcome. While previous studies proposed a chromatin-based mobile enhancer model for ecDNA-driven oncogenesis, its precise mechanism and impact remains unclear across diverse cancer types. Our study, utilizing advanced multi-omics profiling, epigenetic editing, and imaging approaches in three cancer models, reveals that ecDNA hubs are an integrated part of nuclear condensates and exhibit cancer-type specific chromatin connectivity. Epigenetic silencing of the ecDNA-specific regulatory modules or chemically disrupting liquid-liquid phase separation breaks down ecDNA hubs, displaces MED1 co-activator binding, inhibits oncogenic transcription, and promotes cell death. These findings substantiate the trans -activator function of ecDNA and underscore a structural mechanism driving oncogenesis. This refined understanding expands our views of oncogene regulation and opens potential avenues for novel therapeutic strategies in cancer treatment.
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9
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Hills M, Ma L, Fang A, Chiremba T, Malloy S, Scott A, Perera A, Yu CR. Molecular, Cellular, and Developmental Organization of the Mouse Vomeronasal organ at Single Cell Resolution. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.22.581574. [PMID: 39253476 PMCID: PMC11383295 DOI: 10.1101/2024.02.22.581574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
We have generated single cell transcriptomic atlases of vomeronasal organs (VNO) from juvenile and adult mice. Combined with spatial molecular imaging, we uncover a distinct, previously unidentified class of cells that express the vomeronasal receptors and a population of canonical olfactory sensory neurons in the VNO. High resolution trajectory and cluster analyses reveal the lineage relationship, spatial distribution of cell types, and a putative cascade of molecular events that specify the V1r, V2r, and OR lineages from a common stem cell population. The expression of vomeronasal and olfactory receptors follow power law distributions, but there is high variability in average expression levels between individual receptor and cell types. Substantial co-expression is found between receptors across clades, from different classes, and between olfactory and vomeronasal receptors, with nearly half from pairs located on the same chromosome. Interestingly, the expression of V2r, but not V1r, genes is associated with various transcription factors, suggesting distinct mechanisms of receptor choice associated with the two cell types. We identify association between transcription factors, surface axon guidance molecules, and individual VRs, thereby uncovering a molecular code that guides the specification of the vomeronasal circuitry. Our study provides a wealth of data on the development and organization of the accessory olfactory system at both cellular and molecular levels to enable a deeper understanding of vomeronasal system function.
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Affiliation(s)
- Max Hills
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - Limei Ma
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - Ai Fang
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - Thelma Chiremba
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - Seth Malloy
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - Allison Scott
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - Anoja Perera
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
| | - C. Ron Yu
- Stowers Institute for Medical Research, 1000 E. 50 Street, Kansas City, MO 64110, USA
- Department of Cell Biology and Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
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10
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Li H, Playter C, Das P, McCord RP. Chromosome compartmentalization: causes, changes, consequences, and conundrums. Trends Cell Biol 2024; 34:707-727. [PMID: 38395734 PMCID: PMC11339242 DOI: 10.1016/j.tcb.2024.01.009] [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: 10/31/2023] [Revised: 01/12/2024] [Accepted: 01/22/2024] [Indexed: 02/25/2024]
Abstract
The spatial segregation of the genome into compartments is a major feature of 3D genome organization. New data on mammalian chromosome organization across different conditions reveal important information about how and why these compartments form and change. A combination of epigenetic state, nuclear body tethering, physical forces, gene expression, and replication timing (RT) can all influence the establishment and alteration of chromosome compartments. We review the causes and implications of genomic regions undergoing a 'compartment switch' that changes their physical associations and spatial location in the nucleus. About 20-30% of genomic regions change compartment during cell differentiation or cancer progression, whereas alterations in response to a stimulus within a cell type are usually much more limited. However, even a change in 1-2% of genomic bins may have biologically relevant implications. Finally, we review the effects of compartment changes on gene regulation, DNA damage repair, replication, and the physical state of the cell.
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Affiliation(s)
- Heng Li
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Christopher Playter
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Priyojit Das
- University of Tennessee-Oak Ridge National Laboratory (UT-ORNL) Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA
| | - Rachel Patton McCord
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA.
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11
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Lam JC, Aboreden NG, Midla SC, Wang S, Huang A, Keller CA, Giardine B, Henderson KA, Hardison RC, Zhang H, Blobel GA. YY1-controlled regulatory connectivity and transcription are influenced by the cell cycle. Nat Genet 2024; 56:1938-1952. [PMID: 39210046 DOI: 10.1038/s41588-024-01871-y] [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: 11/10/2023] [Accepted: 07/16/2024] [Indexed: 09/04/2024]
Abstract
Few transcription factors have been examined for their direct roles in physically connecting enhancers and promoters. Here acute degradation of Yin Yang 1 (YY1) in erythroid cells revealed its requirement for the maintenance of numerous enhancer-promoter loops, but not compartments or domains. Despite its reported ability to interact with cohesin, the formation of YY1-dependent enhancer-promoter loops does not involve stalling of cohesin-mediated loop extrusion. Integrating mitosis-to-G1-phase dynamics, we observed partial retention of YY1 on mitotic chromatin, predominantly at gene promoters, followed by rapid rebinding during mitotic exit, coinciding with enhancer-promoter loop establishment. YY1 degradation during the mitosis-to-G1-phase interval revealed a set of enhancer-promoter loops that require YY1 for establishment during G1-phase entry but not for maintenance in interphase, suggesting that cell cycle stage influences YY1's architectural function. Thus, as revealed here for YY1, chromatin architectural functions of transcription factors can vary in their interplay with CTCF and cohesin as well as by cell cycle stage.
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Affiliation(s)
- Jessica C Lam
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nicholas G Aboreden
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Susannah C Midla
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Siqing Wang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Anran Huang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Cheryl A Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
- Genomics Research Incubator, Pennsylvania State University, University Park, PA, USA
| | - Belinda Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Kate A Henderson
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Haoyue Zhang
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Gerd A Blobel
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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12
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Aboreden NG, Lam JC, Goel VY, Wang S, Wang X, Midla SC, Quijano A, Keller CA, Giardine BM, Hardison RC, Zhang H, Hansen AS, Blobel GA. LDB1 establishes multi-enhancer networks to regulate gene expression. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.23.609430. [PMID: 39229045 PMCID: PMC11370584 DOI: 10.1101/2024.08.23.609430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
How specific enhancer-promoter pairing is established is still mostly unclear. Besides the CTCF/cohesin machinery, only a few nuclear factors have been studied for a direct role in physically connecting regulatory elements. Here, we show via acute degradation experiments that LDB1 directly and broadly promotes enhancer-promoter loops. Most LDB1-mediated contacts, even those spanning hundreds of kb, can form in the absence of CTCF, cohesin, or YY1 as determined via the use of multiple degron systems. Moreover, an engineered LDB1-driven chromatin loop is cohesin independent. Cohesin-driven loop extrusion does not stall at LDB1 occupied sites but may aid the formation of a subset of LDB1 anchored loops. Leveraging the dynamic reorganization of nuclear architecture during the transition from mitosis to G1-phase, we establish a relationship between LDB1-dependent interactions in the context of TAD organization and gene activation. Lastly, Tri-C and Region Capture Micro-C reveal that LDB1 organizes multi-enhancer networks to activate transcription. This establishes LDB1 as a direct driver of regulatory network inter-connectivity.
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Affiliation(s)
- Nicholas G. Aboreden
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jessica C. Lam
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Viraat Y. Goel
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
| | - Siqing Wang
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Xiaokang Wang
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Susannah C. Midla
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Alma Quijano
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Cheryl A. Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Belinda M. Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Ross C. Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Haoyue Zhang
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, Guangdong, China
| | - Anders S. Hansen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
| | - Gerd A. Blobel
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
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13
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Kawaoka J, Lomvardas S. Barcoding distinct neurons. Science 2024; 385:370-371. [PMID: 39052818 DOI: 10.1126/science.adq5225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
The genomic landscape of a cell surface protein reveals how neuron identity is displayed.
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Affiliation(s)
- Jane Kawaoka
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Stavros Lomvardas
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
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14
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Fan C, Xing X, Murphy SJH, Poursine-Laurent J, Schmidt H, Parikh BA, Yoon J, Choudhary MNK, Saligrama N, Piersma SJ, Yokoyama WM, Wang T. Cis-regulatory evolution of the recently expanded Ly49 gene family. Nat Commun 2024; 15:4839. [PMID: 38844462 PMCID: PMC11156856 DOI: 10.1038/s41467-024-48990-y] [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: 11/13/2023] [Accepted: 05/14/2024] [Indexed: 06/09/2024] Open
Abstract
Comparative genomics has revealed the rapid expansion of multiple gene families involved in immunity. Members within each gene family often evolved distinct roles in immunity. However, less is known about the evolution of their epigenome and cis-regulation. Here we systematically profile the epigenome of the recently expanded murine Ly49 gene family that mainly encode either inhibitory or activating surface receptors on natural killer cells. We identify a set of cis-regulatory elements (CREs) for activating Ly49 genes. In addition, we show that in mice, inhibitory and activating Ly49 genes are regulated by two separate sets of proximal CREs, likely resulting from lineage-specific losses of CRE activity. Furthermore, we find that some Ly49 genes are cross-regulated by the CREs of other Ly49 genes, suggesting that the Ly49 family has begun to evolve a concerted cis-regulatory mechanism. Collectively, we demonstrate the different modes of cis-regulatory evolution for a rapidly expanding gene family.
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Affiliation(s)
- Changxu Fan
- Department of Genetics, Washington University School of Medicine, St. Louis, 63110, USA
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St. Louis, 63110, USA
| | - Xiaoyun Xing
- Department of Genetics, Washington University School of Medicine, St. Louis, 63110, USA
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St. Louis, 63110, USA
| | - Samuel J H Murphy
- Department of Neurology, Washington University School of Medicine, St. Louis, 63110, USA
- Medical Scientist Training Program, Washington University School of Medicine, St. Louis, 63110, USA
| | - Jennifer Poursine-Laurent
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, 63110, USA
| | - Heather Schmidt
- Department of Genetics, Washington University School of Medicine, St. Louis, 63110, USA
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St. Louis, 63110, USA
| | - Bijal A Parikh
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, 63110, USA
| | - Jeesang Yoon
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, 63110, USA
| | - Mayank N K Choudhary
- Department of Genetics, Washington University School of Medicine, St. Louis, 63110, USA
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St. Louis, 63110, USA
| | - Naresha Saligrama
- Department of Neurology, Washington University School of Medicine, St. Louis, 63110, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, 63110, USA
- Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St. Louis, 63110, USA
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, 63110, USA
- Center for Brain Immunology and Glia (BIG), Washington University School of Medicine, St. Louis, 63110, USA
| | - Sytse J Piersma
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, 63110, USA.
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, 63110, USA.
| | - Wayne M Yokoyama
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, 63110, USA.
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, 63110, USA.
| | - Ting Wang
- Department of Genetics, Washington University School of Medicine, St. Louis, 63110, USA.
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine, St. Louis, 63110, USA.
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, 63110, USA.
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15
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Rufenacht KE, Asson AJ, Hossain K, Santoro SW. The influence of olfactory experience on the birthrates of olfactory sensory neurons with specific odorant receptor identities. Genesis 2024; 62:e23611. [PMID: 38888221 PMCID: PMC11189617 DOI: 10.1002/dvg.23611] [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: 04/26/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/20/2024]
Abstract
Olfactory sensory neurons (OSNs) are one of a few neuron types that are generated continuously throughout life in mammals. The persistence of olfactory sensory neurogenesis beyond early development has long been thought to function simply to replace neurons that are lost or damaged through exposure to environmental insults. The possibility that olfactory sensory neurogenesis may also serve an adaptive function has received relatively little consideration, largely due to the assumption that the generation of new OSNs is stochastic with respect to OSN subtype, as defined by the single odorant receptor gene that each neural precursor stochastically chooses for expression out of hundreds of possibilities. Accordingly, the relative birthrates of different OSN subtypes are predicted to be constant and impervious to olfactory experience. This assumption has been called into question, however, by evidence that the birthrates of specific OSN subtypes can be selectively altered by manipulating olfactory experience through olfactory deprivation, enrichment, and conditioning paradigms. Moreover, studies of recovery of the OSN population following injury provide further evidence that olfactory sensory neurogenesis may not be strictly stochastic with respect to subtype. Here we review this evidence and consider mechanistic and functional implications of the prospect that specific olfactory experiences can regulate olfactory sensory neurogenesis rates in a subtype-selective manner.
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Affiliation(s)
- Karlin E Rufenacht
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexa J Asson
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Kawsar Hossain
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Stephen W Santoro
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
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16
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Kawaoka J, Lomvardas S. LiMCA: Hi-C gets an RNA twist. Nat Methods 2024; 21:934-935. [PMID: 38622458 DOI: 10.1038/s41592-024-02205-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Affiliation(s)
- Jane Kawaoka
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
- Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, NY, USA
| | - Stavros Lomvardas
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA.
- Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, NY, USA.
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17
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Wu H, Zhang J, Jian F, Chen JP, Zheng Y, Tan L, Sunney Xie X. Simultaneous single-cell three-dimensional genome and gene expression profiling uncovers dynamic enhancer connectivity underlying olfactory receptor choice. Nat Methods 2024; 21:974-982. [PMID: 38622459 PMCID: PMC11166570 DOI: 10.1038/s41592-024-02239-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 03/07/2024] [Indexed: 04/17/2024]
Abstract
The simultaneous measurement of three-dimensional (3D) genome structure and gene expression of individual cells is critical for understanding a genome's structure-function relationship, yet this is challenging for existing methods. Here we present 'Linking mRNA to Chromatin Architecture (LiMCA)', which jointly profiles the 3D genome and transcriptome with exceptional sensitivity and from low-input materials. Combining LiMCA and our high-resolution scATAC-seq assay, METATAC, we successfully characterized chromatin accessibility, as well as paired 3D genome structures and gene expression information, of individual developing olfactory sensory neurons. We expanded the repertoire of known olfactory receptor (OR) enhancers and discovered unexpected rules of their dynamics: OR genes and their enhancers are most accessible during early differentiation. Furthermore, we revealed the dynamic spatial relationship between ORs and enhancers behind stepwise OR expression. These findings offer valuable insights into how 3D connectivity of ORs and enhancers dynamically orchestrate the 'one neuron-one receptor' selection process.
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Affiliation(s)
- Honggui Wu
- Biomedical Pioneering Innovation Center (BIOPIC), and School of Life Sciences, Peking University, Beijing, China
- Changping Laboratory, Beijing, China
| | - Jiankun Zhang
- Biomedical Pioneering Innovation Center (BIOPIC), and School of Life Sciences, Peking University, Beijing, China
- Changping Laboratory, Beijing, China
| | - Fanchong Jian
- Biomedical Pioneering Innovation Center (BIOPIC), and School of Life Sciences, Peking University, Beijing, China
- Changping Laboratory, Beijing, China
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Jinxin Phaedo Chen
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Yinghui Zheng
- Biomedical Pioneering Innovation Center (BIOPIC), and School of Life Sciences, Peking University, Beijing, China
| | - Longzhi Tan
- Department of Neurobiology, Stanford University, Stanford, CA, USA.
| | - X Sunney Xie
- Biomedical Pioneering Innovation Center (BIOPIC), and School of Life Sciences, Peking University, Beijing, China.
- Changping Laboratory, Beijing, China.
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18
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Bower G, Hollingsworth EW, Jacinto S, Clock B, Cao K, Liu M, Dziulko A, Alcaina-Caro A, Xu Q, Skowronska-Krawczyk D, Lopez-Rios J, Dickel DE, Bardet AF, Pennacchio LA, Visel A, Kvon EZ. Conserved Cis-Acting Range Extender Element Mediates Extreme Long-Range Enhancer Activity in Mammals. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.26.595809. [PMID: 38826394 PMCID: PMC11142232 DOI: 10.1101/2024.05.26.595809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
While most mammalian enhancers regulate their cognate promoters over moderate distances of tens of kilobases (kb), some enhancers act over distances in the megabase range. The sequence features enabling such extreme-distance enhancer-promoter interactions remain elusive. Here, we used in vivo enhancer replacement experiments in mice to show that short- and medium-range enhancers cannot initiate gene expression at extreme-distance range. We uncover a novel conserved cis-acting element, Range EXtender (REX), that confers extreme-distance regulatory activity and is located next to a long-range enhancer of Sall1. The REX element itself has no endogenous enhancer activity. However, addition of the REX to other short- and mid-range enhancers substantially increases their genomic interaction range. In the most extreme example observed, addition of the REX increased the range of an enhancer by an order of magnitude, from its native 71kb to 840kb. The REX element contains highly conserved [C/T]AATTA homeodomain motifs. These motifs are enriched around long-range limb enhancers genome-wide, including the ZRS, a benchmark long-range limb enhancer of Shh. Mutating the [C/T]AATTA motifs within the ZRS does not affect its limb-specific enhancer activity at short range, but selectively abolishes its long-range activity, resulting in severe limb reduction in knock-in mice. In summary, we identify a sequence signature globally associated with long-range enhancer-promoter interactions and describe a prototypical REX element that is necessary and sufficient to confer extreme-distance gene activation by remote enhancers.
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Affiliation(s)
- Grace Bower
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
| | - Ethan W. Hollingsworth
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
- Medical Scientist Training Program, University of California, Irvine, CA 92967, USA
| | - Sandra Jacinto
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
| | - Benjamin Clock
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
| | - Kaitlyn Cao
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
| | - Mandy Liu
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
| | - Adam Dziulko
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ana Alcaina-Caro
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, 41013, Spain
| | - Qianlan Xu
- Department of Physiology and Biophysics, Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, University of California, Irvine, CA, USA
| | - Dorota Skowronska-Krawczyk
- Department of Physiology and Biophysics, Department of Ophthalmology, Center for Translational Vision Research, School of Medicine, University of California, Irvine, CA, USA
| | - Javier Lopez-Rios
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, 41013, Spain
| | - Diane E. Dickel
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Anaïs F. Bardet
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS UMR7104, INSERM U1258, 67400 Illkirch, France
| | - Len A. Pennacchio
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA
- Comparative Biochemistry Program, University of California, Berkeley, CA 94720, USA
| | - Axel Visel
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA
- School of Natural Sciences, University of California, Merced, CA 95343, USA
| | - Evgeny Z. Kvon
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92967, USA
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19
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Kanata E, Duffié R, Schulz EG. Establishment and maintenance of random monoallelic expression. Development 2024; 151:dev201741. [PMID: 38813842 PMCID: PMC11166465 DOI: 10.1242/dev.201741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
This Review elucidates the regulatory principles of random monoallelic expression by focusing on two well-studied examples: the X-chromosome inactivation regulator Xist and the olfactory receptor gene family. Although the choice of a single X chromosome or olfactory receptor occurs in different developmental contexts, common gene regulatory principles guide monoallelic expression in both systems. In both cases, an event breaks the symmetry between genetically and epigenetically identical copies of the gene, leading to the expression of one single random allele, stabilized through negative feedback control. Although many regulatory steps that govern the establishment and maintenance of monoallelic expression have been identified, key pieces of the puzzle are still missing. We provide an overview of the current knowledge and models for the monoallelic expression of Xist and olfactory receptors. We discuss their similarities and differences, and highlight open questions and approaches that could guide the study of other monoallelically expressed genes.
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Affiliation(s)
- Eleni Kanata
- Systems Epigenetics, Otto Warburg Laboratories, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Rachel Duffié
- Department of Biochemistry and Molecular Biophysics, Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Edda G. Schulz
- Systems Epigenetics, Otto Warburg Laboratories, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
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20
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Tomikawa J. Potential roles of inter-chromosomal interactions in cell fate determination. Front Cell Dev Biol 2024; 12:1397807. [PMID: 38774644 PMCID: PMC11106443 DOI: 10.3389/fcell.2024.1397807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 04/23/2024] [Indexed: 05/24/2024] Open
Abstract
Mammalian genomic DNA is packed in a small nucleus, and its folding and organization in the nucleus are critical for gene regulation and cell fate determination. In interphase, chromosomes are compartmentalized into certain nuclear spaces and territories that are considered incompatible with each other. The regulation of gene expression is influenced by the epigenetic characteristics of topologically associated domains and A/B compartments within chromosomes (intrachromosomal). Previously, interactions among chromosomes detected via chromosome conformation capture-based methods were considered noise or artificial errors. However, recent studies based on newly developed ligation-independent methods have shown that inter-chromosomal interactions play important roles in gene regulation. This review summarizes the recent understanding of spatial genomic organization in mammalian interphase nuclei and discusses the potential mechanisms that determine cell identity. In addition, this review highlights the potential role of inter-chromosomal interactions in early mouse development.
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Affiliation(s)
- Junko Tomikawa
- Department of Maternal-Fetal Biology, National Research Institute for Child Health and Development, Tokyo, Japan
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21
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Ordway AJ, Helt RN, Johnston RJ. Transcriptional priming and chromatin regulation during stochastic cell fate specification. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230046. [PMID: 38432315 PMCID: PMC10909510 DOI: 10.1098/rstb.2023.0046] [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: 08/21/2023] [Accepted: 01/19/2024] [Indexed: 03/05/2024] Open
Abstract
Stochastic cell fate specification, in which a cell chooses between two or more fates with a set probability, diversifies cell subtypes in development. Although this is a vital process across species, a common mechanism for these cell fate decisions remains elusive. This review examines two well-characterized stochastic cell fate decisions to identify commonalities between their developmental programmes. In the fly eye, two subtypes of R7 photoreceptors are specified by the stochastic ON/OFF expression of a transcription factor, spineless. In the mouse olfactory system, olfactory sensory neurons (OSNs) randomly select to express one copy of an olfactory receptor (OR) gene out of a pool of 2800 alleles. Despite the differences in these sensory systems, both stochastic fate choices rely on the dynamic interplay between transcriptional priming, chromatin regulation and terminal gene expression. The coupling of transcription and chromatin modifications primes gene loci in undifferentiated neurons, enabling later expression during terminal differentiation. Here, we compare these mechanisms, examine broader implications for gene regulation during development and posit key challenges moving forward. This article is part of a discussion meeting issue 'Causes and consequences of stochastic processes in development and disease'.
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Affiliation(s)
- Alison J. Ordway
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Rina N. Helt
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Robert J. Johnston
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
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22
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Yusuf N, Monahan K. Epigenetic programming of stochastic olfactory receptor choice. Genesis 2024; 62:e23593. [PMID: 38562011 PMCID: PMC11003729 DOI: 10.1002/dvg.23593] [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: 11/27/2023] [Revised: 03/01/2024] [Accepted: 03/15/2024] [Indexed: 04/04/2024]
Abstract
The mammalian sense of smell relies upon a vast array of receptor proteins to detect odorant compounds present in the environment. The proper deployment of these receptor proteins in olfactory sensory neurons is orchestrated by a suite of epigenetic processes that remodel the olfactory genes in differentiating neuronal progenitors. The goal of this review is to elucidate the central role of gene regulatory processes acting in neuronal progenitors of olfactory sensory neurons that lead to a singular expression of an odorant receptor in mature olfactory sensory neurons. We begin by describing the principal features of odorant receptor gene expression in mature olfactory sensory neurons. Next, we delineate our current understanding of how these features emerge from multiple gene regulatory mechanisms acting in neuronal progenitors. Finally, we close by discussing the key gaps in our understanding of how these regulatory mechanisms work and how they interact with each other over the course of differentiation.
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Affiliation(s)
- Nusrath Yusuf
- Division of Life Sciences-Molecular Biology and Biochemistry Department, Rutgers University-New Brunswick, New Brunswick, New Jersey, USA
| | - Kevin Monahan
- Division of Life Sciences-Molecular Biology and Biochemistry Department, Rutgers University-New Brunswick, New Brunswick, New Jersey, USA
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23
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Raja R, Dumontier E, Phen A, Cloutier JF. Insertion of a neomycin selection cassette in the Amigo1 locus alters gene expression in the olfactory epithelium leading to region-specific defects in olfactory receptor neuron development. Genesis 2024; 62:e23594. [PMID: 38590146 DOI: 10.1002/dvg.23594] [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: 12/04/2023] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/10/2024]
Abstract
During development of the nervous system, neurons connect to one another in a precisely organized manner. Sensory systems provide a good example of this organization, whereby the composition of the outside world is represented in the brain by neuronal maps. Establishing correct patterns of neural circuitry is crucial, as inaccurate map formation can lead to severe disruptions in sensory processing. In rodents, olfactory stimuli modulate a wide variety of behaviors essential for survival. The formation of the olfactory glomerular map is dependent on molecular cues that guide olfactory receptor neuron axons to broad regions of the olfactory bulb and on cell adhesion molecules that promote axonal sorting into specific synaptic units in this structure. Here, we demonstrate that the cell adhesion molecule Amigo1 is expressed in a subpopulation of olfactory receptor neurons, and we investigate its role in the precise targeting of olfactory receptor neuron axons to the olfactory bulb using a genetic loss-of-function approach in mice. While ablation of Amigo1 did not lead to alterations in olfactory sensory neuron axonal targeting, our experiments revealed that the presence of a neomycin resistance selection cassette in the Amigo1 locus can lead to off-target effects that are not due to loss of Amigo1 expression, including unexpected altered gene expression in olfactory receptor neurons and reduced glomerular size in the ventral region of the olfactory bulb. Our results demonstrate that insertion of a neomycin selection cassette into the mouse genome can have specific deleterious effects on the development of the olfactory system and highlight the importance of removing antibiotic resistance cassettes from genetic loss-of-function mouse models when studying olfactory system development.
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Affiliation(s)
- Reesha Raja
- The Neuro (Montreal Neurological Institute-Hospital), Montréal, Québec, Canada
- Integrated Program in Neuroscience, McGill University, Montréal, Québec, Canada
| | - Emilie Dumontier
- The Neuro (Montreal Neurological Institute-Hospital), Montréal, Québec, Canada
| | - Alina Phen
- The Neuro (Montreal Neurological Institute-Hospital), Montréal, Québec, Canada
| | - Jean-François Cloutier
- The Neuro (Montreal Neurological Institute-Hospital), Montréal, Québec, Canada
- Integrated Program in Neuroscience, McGill University, Montréal, Québec, Canada
- Department of Neurology and Neurosurgery, McGill University, Montréal, Québec, Canada
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24
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Hirota J. Molecular mechanisms of differentiation and class choice of olfactory sensory neurons. Genesis 2024; 62:e23587. [PMID: 38454646 DOI: 10.1002/dvg.23587] [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: 11/13/2023] [Revised: 01/10/2024] [Accepted: 01/29/2024] [Indexed: 03/09/2024]
Abstract
The sense of smell is intricately linked to essential animal behaviors necessary for individual survival and species preservation. During vertebrate evolution, odorant receptors (ORs), responsible for detecting odor molecules, have evolved to adapt to changing environments, transitioning from aquatic to terrestrial habitats and accommodating increasing complex chemical environments. These evolutionary pressures have given rise to the largest gene family in vertebrate genomes. Vertebrate ORs are phylogenetically divided into two major classes; class I and class II. Class I OR genes, initially identified in fish and frog, have persisted across vertebrate species. On the other hand, class II OR genes are unique to terrestrial animals, accounting for ~90% of mammalian OR genes. In mice, each olfactory sensory neuron (OSN) expresses a single functional allele of a single OR gene from either the class I or class II OR repertoire. This one neuron-one receptor rule is established through two sequential steps: specification of OR class and subsequent exclusive OR expression from the corresponding OR class. Consequently, OSNs acquire diverse neuronal identities during the process of OSN differentiation, enabling animals to detect a wide array of odor molecules. This review provides an overview of the OSN differentiation process through which OSN diversity is achieved, primarily using the mouse as a model animal.
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Affiliation(s)
- Junji Hirota
- Department of Life Science and Technology, Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
- Center for Integrative Biosciences, Tokyo Institute of Technology, Yokohama, Japan
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25
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Ibrahim DM. Enhancer contacts during embryonic development show diverse interaction modes and modest yet significant increases upon gene activation. Nat Genet 2024; 56:558-560. [PMID: 38528242 DOI: 10.1038/s41588-024-01700-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Affiliation(s)
- Daniel M Ibrahim
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Center for Regenerative Therapies, Berlin, Germany.
- Max Planck Institute for Molecular Genetics, Berlin, Germany.
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26
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Serra F, Nieto-Aliseda A, Fanlo-Escudero L, Rovirosa L, Cabrera-Pasadas M, Lazarenkov A, Urmeneta B, Alcalde-Merino A, Nola EM, Okorokov AL, Fraser P, Graupera M, Castillo SD, Sardina JL, Valencia A, Javierre BM. p53 rapidly restructures 3D chromatin organization to trigger a transcriptional response. Nat Commun 2024; 15:2821. [PMID: 38561401 PMCID: PMC10984980 DOI: 10.1038/s41467-024-46666-1] [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: 06/15/2023] [Accepted: 03/04/2024] [Indexed: 04/04/2024] Open
Abstract
Activation of the p53 tumor suppressor triggers a transcriptional program to control cellular response to stress. However, the molecular mechanisms by which p53 controls gene transcription are not completely understood. Here, we uncover the critical role of spatio-temporal genome architecture in this process. We demonstrate that p53 drives direct and indirect changes in genome compartments, topologically associating domains, and DNA loops prior to one hour of its activation, which escort the p53 transcriptional program. Focusing on p53-bound enhancers, we report 340 genes directly regulated by p53 over a median distance of 116 kb, with 74% of these genes not previously identified. Finally, we showcase that p53 controls transcription of distal genes through newly formed and pre-existing enhancer-promoter loops in a cohesin dependent manner. Collectively, our findings demonstrate a previously unappreciated architectural role of p53 as regulator at distinct topological layers and provide a reliable set of new p53 direct target genes that may help designs of cancer therapies.
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Affiliation(s)
- François Serra
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain
| | | | | | | | - Mónica Cabrera-Pasadas
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain
- Barcelona Supercomputing Center, Barcelona, Spain
| | | | - Blanca Urmeneta
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain
| | | | - Emanuele M Nola
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain
| | - Andrei L Okorokov
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Peter Fraser
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Mariona Graupera
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
- CIBERONC, Instituto de Salud Carlos III, Madrid, Spain
| | | | - Jose L Sardina
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain
| | - Alfonso Valencia
- Barcelona Supercomputing Center, Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - Biola M Javierre
- Josep Carreras Leukaemia Research Institute, Barcelona, Spain.
- Institute for Health Science Research Germans Trias i Pujol, Barcelona, Spain.
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27
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Ishii C, Nakano H, Higashiseto R, Ooki Y, Umemura M, Takahashi S, Takahashi Y. Nescient helix-loop-helix 1 (Nhlh1) is a novel activating transcription factor 5 (ATF5) target gene in olfactory and vomeronasal sensory neurons in mice. Cell Tissue Res 2024; 396:85-94. [PMID: 38388750 DOI: 10.1007/s00441-024-03871-0] [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: 09/13/2023] [Accepted: 01/23/2024] [Indexed: 02/24/2024]
Abstract
Activating transcription factor 5 (ATF5) is a transcription factor that belongs to the cAMP-response element-binding protein/ATF family and is essential for the differentiation and survival of sensory neurons in mouse olfactory organs. However, transcriptional target genes for ATF5 have yet to be identified. In the present study, chromatin immunoprecipitation-quantitative polymerase chain reaction (ChIP-qPCR) experiments were performed to verify ATF5 target genes in the main olfactory epithelium and vomeronasal organ in the postnatal pups. ChIP-qPCR was conducted using hemagglutinin (HA)-tagged ATF5 knock-in olfactory organs. The results obtained demonstrated that ATF5-HA fusion proteins bound to the CCAAT/enhancer-binding protein-ATF response element (CARE) site in the enhancer region of nescient helix-loop-helix 1 (Nhlh1), a transcription factor expressed in differentiating olfactory and vomeronasal sensory neurons. Nhlh1 mRNA expression was downregulated in ATF5-deficient (ATF5-/-) olfactory organs. The LIM/homeobox protein transcription factor Lhx2 co-localized with ATF5 in the nuclei of olfactory and vomeronasal sensory neurons and bound to the homeodomain site proximal to the CARE site in the Nhlh1 gene. The CARE region of the Nhlh1 gene was enriched by the active enhancer marker, acetyl-histone H3 (Lys27). The present study identified Nhlh1 as a novel target gene for ATF5 in murine olfactory organs. ATF5 may upregulate Nhlh1 expression in concert with Lhx2, thereby promoting the differentiation of olfactory and vomeronasal sensory neurons.
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Affiliation(s)
- Chiharu Ishii
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Haruo Nakano
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan.
| | - Riko Higashiseto
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Yusaku Ooki
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Mariko Umemura
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Shigeru Takahashi
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Yuji Takahashi
- Laboratory of Environmental Molecular Physiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 192-0392, Japan
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28
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Huang L, Zhang J, Songyang Z, Xiong Y. Identification and Validation of eRNA as a Prognostic Indicator for Cervical Cancer. BIOLOGY 2024; 13:227. [PMID: 38666838 PMCID: PMC11048606 DOI: 10.3390/biology13040227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/22/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024]
Abstract
The survival of CESC patients is closely related to the expression of enhancer RNA (eRNA). In this work, we downloaded eRNA expression, clinical, and gene expression data from the TCeA and TCGA portals. A total of 7936 differentially expressed eRNAs were discovered by limma analysis, and the relationship between these eRNAs and survival was analyzed by univariate Cox hazard analysis, LASSO regression, and multivariate Cox hazard analysis to obtain an 8-eRNA model. Risk score heat maps, KM curves, ROC analysis, robustness analysis, and nomograms further indicate that this 8-eRNA model is a novel indicator with high prognostic performance independent of clinicopathological classification. The model divided patients into high-risk and low-risk groups, compared pathway diversity between the two groups through GSEA analysis, and provided potential therapeutic agents for high-risk patients.
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Affiliation(s)
- Lijing Huang
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; (L.H.); (J.Z.)
| | - Jingkai Zhang
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; (L.H.); (J.Z.)
| | - Zhou Songyang
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; (L.H.); (J.Z.)
- Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Yuanyan Xiong
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; (L.H.); (J.Z.)
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29
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Pollex T, Marco-Ferreres R, Ciglar L, Ghavi-Helm Y, Rabinowitz A, Viales RR, Schaub C, Jankowski A, Girardot C, Furlong EEM. Chromatin gene-gene loops support the cross-regulation of genes with related function. Mol Cell 2024; 84:822-838.e8. [PMID: 38157845 DOI: 10.1016/j.molcel.2023.12.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/31/2023] [Accepted: 12/14/2023] [Indexed: 01/03/2024]
Abstract
Chromatin loops between gene pairs have been observed in diverse contexts in both flies and vertebrates. Combining high-resolution Capture-C, DNA fluorescence in situ hybridization, and genetic perturbations, we dissect the functional role of three loops between genes with related function during Drosophila embryogenesis. By mutating the loop anchor (but not the gene) or the gene (but not loop anchor), we disentangle loop formation and gene expression and show that the 3D proximity of paralogous gene loci supports their co-regulation. Breaking the loop leads to either an attenuation or enhancement of expression and perturbs their relative levels of expression and cross-regulation. Although many loops appear constitutive across embryogenesis, their function can change in different developmental contexts. Taken together, our results indicate that chromatin gene-gene loops act as architectural scaffolds that can be used in different ways in different contexts to fine-tune the coordinated expression of genes with related functions and sustain their cross-regulation.
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Affiliation(s)
- Tim Pollex
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Raquel Marco-Ferreres
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Lucia Ciglar
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Yad Ghavi-Helm
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Adam Rabinowitz
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | | | - Christoph Schaub
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Aleksander Jankowski
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Charles Girardot
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Eileen E M Furlong
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany.
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30
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Hao Y, Qian KY, Li Q. A noncoding role of coding mRNA in monogenic olfactory receptor choice. Trends Neurosci 2024; 47:167-169. [PMID: 38378395 DOI: 10.1016/j.tins.2024.02.004] [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: 01/31/2024] [Accepted: 02/09/2024] [Indexed: 02/22/2024]
Abstract
In a recent study, Pourmorady and colleagues uncovered a noncoding role for olfactory receptor (OR)-coding mRNA in mediating nuclear architecture and singular OR choice. The OR mRNAs reinforce the prevailing enhancer hub and inhibit other competitors, facilitating transition from polygenic to singular OR expression.
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Affiliation(s)
- Yue Hao
- Songjiang Hospital and Songjiang Research Institute, Shanghai Key Laboratory of Emotions and Affective Disorders, Shanghai Jiao Tong University School of Medicine, Shanghai 201600, China; Department of Anatomy and Physiology, Ministry of Education-Shanghai Key Laboratory of Children's Environmental Health in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Kang-Ying Qian
- Songjiang Hospital and Songjiang Research Institute, Shanghai Key Laboratory of Emotions and Affective Disorders, Shanghai Jiao Tong University School of Medicine, Shanghai 201600, China; Department of Anatomy and Physiology, Ministry of Education-Shanghai Key Laboratory of Children's Environmental Health in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Qian Li
- Songjiang Hospital and Songjiang Research Institute, Shanghai Key Laboratory of Emotions and Affective Disorders, Shanghai Jiao Tong University School of Medicine, Shanghai 201600, China; Department of Anatomy and Physiology, Ministry of Education-Shanghai Key Laboratory of Children's Environmental Health in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
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31
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Ren L, Ma W, Wang Y. SpecLoop predicts cell type-specific chromatin loop via transcription factor cooperation. Comput Biol Med 2024; 171:108182. [PMID: 38422958 DOI: 10.1016/j.compbiomed.2024.108182] [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: 11/07/2023] [Revised: 01/18/2024] [Accepted: 02/18/2024] [Indexed: 03/02/2024]
Abstract
Cell-type-Specific Chromatin Loops (CSCLs) are crucial for gene regulation and cell fate determination. However, the mechanisms governing their establishment remain elusive. Here, we present SpecLoop, a network regularization-based machine learning framework, to investigate the role of transcription factors (TFs) cooperation in CSCL formation. SpecLoop integrates multi-omics data, including gene expression, chromatin accessibility, sequence, protein-protein interaction, and TF binding motif data, to predict CSCLs and identify TF cooperations. Using high resolution Hi-C data as the gold standard, SpecLoop accurately predicts CSCL in GM12878, IMR90, HeLa-S3, K562, HUVEC, HMEC, and NHEK seven cell types, with the AUROC values ranging from 0.8645 to 0.9852 and AUPR values ranging from 0.8654 to 0.9734. Notably SpecLoop demonstrates improved accuracy in predicting long-distance CSCLs and identifies TF complexes with strong predictive ability. Our study systematically explores the TFs and TF pairs associated with CSCL through effective integration of diverse omics data. SpecLoop is freely available at https://github.com/AMSSwanglab/SpecLoop.
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Affiliation(s)
- Lixin Ren
- Department of Applied Mathematics, School of Mathematics and Physics, University of Science and Technology Beijing, 100083, Beijing, China.
| | - Wanbiao Ma
- Department of Applied Mathematics, School of Mathematics and Physics, University of Science and Technology Beijing, 100083, Beijing, China.
| | - Yong Wang
- CEMS, NCMIS, HCMS, MDIS, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing, 100190, China; School of Mathematical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, China; Key Laboratory of Systems Biology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou, 330106, China.
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32
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Wahl N, Espeso-Gil S, Chietera P, Nagel A, Laighneach A, Morris DW, Rajarajan P, Akbarian S, Dechant G, Apostolova G. SATB2 organizes the 3D genome architecture of cognition in cortical neurons. Mol Cell 2024; 84:621-639.e9. [PMID: 38244545 PMCID: PMC10923151 DOI: 10.1016/j.molcel.2023.12.024] [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: 01/27/2023] [Revised: 10/02/2023] [Accepted: 12/15/2023] [Indexed: 01/22/2024]
Abstract
The DNA-binding protein SATB2 is genetically linked to human intelligence. We studied its influence on the three-dimensional (3D) epigenome by mapping chromatin interactions and accessibility in control versus SATB2-deficient cortical neurons. We find that SATB2 affects the chromatin looping between enhancers and promoters of neuronal-activity-regulated genes, thus influencing their expression. It also alters A/B compartments, topologically associating domains, and frequently interacting regions. Genes linked to SATB2-dependent 3D genome changes are implicated in highly specialized neuronal functions and contribute to cognitive ability and risk for neuropsychiatric and neurodevelopmental disorders. Non-coding DNA regions with a SATB2-dependent structure are enriched for common variants associated with educational attainment, intelligence, and schizophrenia. Our data establish SATB2 as a cell-type-specific 3D genome modulator, which operates both independently and in cooperation with CCCTC-binding factor (CTCF) to set up the chromatin landscape of pyramidal neurons for cognitive processes.
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Affiliation(s)
- Nico Wahl
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria.
| | - Sergio Espeso-Gil
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria; Department of Psychiatry, Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paola Chietera
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Amelie Nagel
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Aodán Laighneach
- Centre for Neuroimaging, Cognition and Genomics (NICOG), School of Biological and Chemical Sciences, University of Galway, Galway, H91 TK33, Ireland
| | - Derek W Morris
- Centre for Neuroimaging, Cognition and Genomics (NICOG), School of Biological and Chemical Sciences, University of Galway, Galway, H91 TK33, Ireland
| | - Prashanth Rajarajan
- Department of Psychiatry, Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Schahram Akbarian
- Department of Psychiatry, Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Georg Dechant
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria.
| | - Galina Apostolova
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria.
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33
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Destain H, Prahlad M, Kratsios P. Maintenance of neuronal identity in C. elegans and beyond: Lessons from transcription and chromatin factors. Semin Cell Dev Biol 2024; 154:35-47. [PMID: 37438210 PMCID: PMC10592372 DOI: 10.1016/j.semcdb.2023.07.001] [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: 04/26/2023] [Revised: 06/30/2023] [Accepted: 07/01/2023] [Indexed: 07/14/2023]
Abstract
Neurons are remarkably long-lived, non-dividing cells that must maintain their functional features (e.g., electrical properties, chemical signaling) for extended periods of time - decades in humans. How neurons accomplish this incredible feat is poorly understood. Here, we review recent advances, primarily in the nematode C. elegans, that have enhanced our understanding of the molecular mechanisms that enable post-mitotic neurons to maintain their functionality across different life stages. We begin with "terminal selectors" - transcription factors necessary for the establishment and maintenance of neuronal identity. We highlight new findings on five terminal selectors (CHE-1 [Glass], UNC-3 [Collier/Ebf1-4], LIN-39 [Scr/Dfd/Hox4-5], UNC-86 [Acj6/Brn3a-c], AST-1 [Etv1/ER81]) from different transcription factor families (ZNF, COE, HOX, POU, ETS). We compare the functions of these factors in specific neuron types of C. elegans with the actions of their orthologs in other invertebrate (D. melanogaster) and vertebrate (M. musculus) systems, highlighting remarkable functional conservation. Finally, we reflect on recent findings implicating chromatin-modifying proteins, such as histone methyltransferases and Polycomb proteins, in the control of neuronal terminal identity. Altogether, these new studies on transcription factors and chromatin modifiers not only shed light on the fundamental problem of neuronal identity maintenance, but also outline mechanistic principles of gene regulation that may operate in other long-lived, post-mitotic cell types.
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Affiliation(s)
- Honorine Destain
- Department of Neurobiology, University of Chicago, Chicago, IL, USA; Committee on Development, Regeneration and Stem Cell Biology, University of Chicago, Chicago, IL, USA; University of Chicago Neuroscience Institute, Chicago, IL, USA
| | - Manasa Prahlad
- Department of Neurobiology, University of Chicago, Chicago, IL, USA; Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL, USA; University of Chicago Neuroscience Institute, Chicago, IL, USA
| | - Paschalis Kratsios
- Department of Neurobiology, University of Chicago, Chicago, IL, USA; Committee on Development, Regeneration and Stem Cell Biology, University of Chicago, Chicago, IL, USA; Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL, USA; University of Chicago Neuroscience Institute, Chicago, IL, USA.
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34
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Pourmorady AD, Bashkirova EV, Chiariello AM, Belagzhal H, Kodra A, Duffié R, Kahiapo J, Monahan K, Pulupa J, Schieren I, Osterhoudt A, Dekker J, Nicodemi M, Lomvardas S. RNA-mediated symmetry breaking enables singular olfactory receptor choice. Nature 2024; 625:181-188. [PMID: 38123679 PMCID: PMC10765522 DOI: 10.1038/s41586-023-06845-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 11/07/2023] [Indexed: 12/23/2023]
Abstract
Olfactory receptor (OR) choice provides an extreme example of allelic competition for transcriptional dominance, where every olfactory neuron stably transcribes one of approximately 2,000 or more OR alleles1,2. OR gene choice is mediated by a multichromosomal enhancer hub that activates transcription at a single OR3,4, followed by OR-translation-dependent feedback that stabilizes this choice5,6. Here, using single-cell genomics, we show formation of many competing hubs with variable enhancer composition, only one of which retains euchromatic features and transcriptional competence. Furthermore, we provide evidence that OR transcription recruits enhancers and reinforces enhancer hub activity locally, whereas OR RNA inhibits transcription of competing ORs over distance, promoting transition to transcriptional singularity. Whereas OR transcription is sufficient to break the symmetry between equipotent enhancer hubs, OR translation stabilizes transcription at the prevailing hub, indicating that there may be sequential non-coding and coding mechanisms that are implemented by OR alleles for transcriptional prevalence. We propose that coding OR mRNAs possess non-coding functions that influence nuclear architecture, enhance their own transcription and inhibit transcription from their competitors, with generalizable implications for probabilistic cell fate decisions.
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Affiliation(s)
- Ariel D Pourmorady
- Vagelos College of Physicians and Surgeons, Columbia University New York, New York, NY, USA
- Department of Neuroscience, Columbia University, New York, NY, USA
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA
| | - Elizaveta V Bashkirova
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Andrea M Chiariello
- Department of Physics 'Ettore Pancini', University of Naples, and INFN, Napoli, Italy
| | - Houda Belagzhal
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Albana Kodra
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Genetics and Development, Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Rachel Duffié
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA
| | - Jerome Kahiapo
- Department of Molecular Biology & Biochemistry, Rutgers School of Arts and Sciences, Robert Wood Johnson Medical School, Piscataway, NJ, USA
| | - Kevin Monahan
- Department of Molecular Biology & Biochemistry, Rutgers School of Arts and Sciences, Robert Wood Johnson Medical School, Piscataway, NJ, USA
| | - Joan Pulupa
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA
| | - Ira Schieren
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA
| | - Alexa Osterhoudt
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Job Dekker
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Mario Nicodemi
- Department of Physics 'Ettore Pancini', University of Naples, and INFN, Napoli, Italy
| | - Stavros Lomvardas
- Mortimer B. Zuckerman Mind, Brain, and Behavior Institute, Columbia University New York, New York, NY, USA.
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, New York, NY, USA.
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35
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Bashkirova EV, Klimpert N, Monahan K, Campbell CE, Osinski J, Tan L, Schieren I, Pourmorady A, Stecky B, Barnea G, Xie XS, Abdus-Saboor I, Shykind BM, Marlin BJ, Gronostajski RM, Fleischmann A, Lomvardas S. Opposing, spatially-determined epigenetic forces impose restrictions on stochastic olfactory receptor choice. eLife 2023; 12:RP87445. [PMID: 38108811 PMCID: PMC10727497 DOI: 10.7554/elife.87445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023] Open
Abstract
Olfactory receptor (OR) choice represents an example of genetically hardwired stochasticity, where every olfactory neuron expresses one out of ~2000 OR alleles in the mouse genome in a probabilistic, yet stereotypic fashion. Here, we propose that topographic restrictions in OR expression are established in neuronal progenitors by two opposing forces: polygenic transcription and genomic silencing, both of which are influenced by dorsoventral gradients of transcription factors NFIA, B, and X. Polygenic transcription of OR genes may define spatially constrained OR repertoires, among which one OR allele is selected for singular expression later in development. Heterochromatin assembly and genomic compartmentalization of OR alleles also vary across the axes of the olfactory epithelium and may preferentially eliminate ectopically expressed ORs with more dorsal expression destinations from this 'privileged' repertoire. Our experiments identify early transcription as a potential 'epigenetic' contributor to future developmental patterning and reveal how two spatially responsive probabilistic processes may act in concert to establish deterministic, precise, and reproducible territories of stochastic gene expression.
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Affiliation(s)
- Elizaveta V Bashkirova
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, Columbia UniversityNew YorkUnited States
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
| | - Nell Klimpert
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown UniversityProvidenceUnited States
| | - Kevin Monahan
- Department of Biochemistry and Molecular Biology, Rutgers UniversityNewarkUnited States
| | - Christine E Campbell
- Department of Biochemistry, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life SciencesBuffaloUnited States
- Genetics, Genomics, and Bioinformatics Graduate Program, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life SciencesBuffaloUnited States
| | - Jason Osinski
- Department of Biochemistry, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life SciencesBuffaloUnited States
- Genetics, Genomics, and Bioinformatics Graduate Program, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life SciencesBuffaloUnited States
| | - Longzhi Tan
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | - Ira Schieren
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
| | - Ariel Pourmorady
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, Columbia UniversityNew YorkUnited States
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
| | - Beka Stecky
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
| | - Gilad Barnea
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown UniversityProvidenceUnited States
| | - Xiaoliang Sunney Xie
- Beijing Innovation Center for Genomics, Peking UniversityBeijingChina
- Biomedical Pioneering Innovation Center, Peking UniversityBeijingChina
| | - Ishmail Abdus-Saboor
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
| | - Benjamin M Shykind
- Prevail Therapeutics- a wholly-owned subsidiary of Eli Lilly and CompanyNew YorkUnited States
| | - Bianca J Marlin
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
| | - Richard M Gronostajski
- Department of Biochemistry, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life SciencesBuffaloUnited States
- Genetics, Genomics, and Bioinformatics Graduate Program, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life SciencesBuffaloUnited States
| | - Alexander Fleischmann
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown UniversityProvidenceUnited States
| | - Stavros Lomvardas
- Zuckerman Mind, Brain, and Behavior Institute, Columbia UniversityNew YorkUnited States
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, Columbia UniversityNew YorkUnited States
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36
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Faria JRC, Tinti M, Marques CA, Zoltner M, Yoshikawa H, Field MC, Horn D. An allele-selective inter-chromosomal protein bridge supports monogenic antigen expression in the African trypanosome. Nat Commun 2023; 14:8200. [PMID: 38081826 PMCID: PMC10713589 DOI: 10.1038/s41467-023-44043-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
UPF1-like helicases play roles in telomeric heterochromatin formation and X-chromosome inactivation, and also in monogenic variant surface glycoprotein (VSG) expression via VSG exclusion-factor-2 (VEX2), a UPF1-related protein in the African trypanosome. We show that VEX2 associates with chromatin specifically at the single active VSG expression site on chromosome 6, forming an allele-selective connection, via VEX1, to the trans-splicing locus on chromosome 9, physically bridging two chromosomes and the VSG transcription and splicing compartments. We further show that the VEX-complex is multimeric and self-regulates turnover to tightly control its abundance. Using single cell transcriptomics following VEX2-depletion, we observed simultaneous derepression of many other telomeric VSGs and multi-allelic VSG expression in individual cells. Thus, an allele-selective, inter-chromosomal, and self-limiting VEX1-2 bridge supports monogenic VSG expression and multi-allelic VSG exclusion.
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Affiliation(s)
- Joana R C Faria
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK.
- Biology Department, University of York, York, UK.
- York Biomedical Research Institute, University of York, York, UK.
| | - Michele Tinti
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK
| | - Catarina A Marques
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Martin Zoltner
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK
- Faculty of Science, Charles University in Prague, Biocev, Vestec, Czech Republic
| | - Harunori Yoshikawa
- Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK
- Division of Cell Signaling, Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Mark C Field
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK
- Biology Centre, Czech Academy of Sciences, Institute of Parasitology, České Budějovice, Czech Republic
| | - David Horn
- Wellcome Centre for Anti-Infectives Research, Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK.
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37
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Noack F, Vangelisti S, Ditzer N, Chong F, Albert M, Bonev B. Joint epigenome profiling reveals cell-type-specific gene regulatory programmes in human cortical organoids. Nat Cell Biol 2023; 25:1873-1883. [PMID: 37996647 PMCID: PMC10709149 DOI: 10.1038/s41556-023-01296-5] [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: 09/20/2022] [Accepted: 10/17/2023] [Indexed: 11/25/2023]
Abstract
Gene expression is regulated by multiple epigenetic mechanisms, which are coordinated in development and disease. However, current multiomics methods are frequently limited to one or two modalities at a time, making it challenging to obtain a comprehensive gene regulatory signature. Here, we describe a method-3D genome, RNA, accessibility and methylation sequencing (3DRAM-seq)-that simultaneously interrogates spatial genome organization, chromatin accessibility and DNA methylation genome-wide and at high resolution. We combine 3DRAM-seq with immunoFACS and RNA sequencing in cortical organoids to map the cell-type-specific regulatory landscape of human neural development across multiple epigenetic layers. Finally, we apply a massively parallel reporter assay to profile cell-type-specific enhancer activity in organoids and to functionally assess the role of key transcription factors for human enhancer activation and function. More broadly, 3DRAM-seq can be used to profile the multimodal epigenetic landscape in rare cell types and different tissues.
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Affiliation(s)
- Florian Noack
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany
| | - Silvia Vangelisti
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany
| | - Nora Ditzer
- Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany
| | - Faye Chong
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany
| | - Mareike Albert
- Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany
| | - Boyan Bonev
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany.
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, Munich, Germany.
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38
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Hu Y, Salgado Figueroa D, Zhang Z, Veselits M, Bhattacharyya S, Kashiwagi M, Clark MR, Morgan BA, Ay F, Georgopoulos K. Lineage-specific 3D genome organization is assembled at multiple scales by IKAROS. Cell 2023; 186:5269-5289.e22. [PMID: 37995656 PMCID: PMC10895928 DOI: 10.1016/j.cell.2023.10.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/28/2023] [Accepted: 10/25/2023] [Indexed: 11/25/2023]
Abstract
A generic level of chromatin organization generated by the interplay between cohesin and CTCF suffices to limit promiscuous interactions between regulatory elements, but a lineage-specific chromatin assembly that supersedes these constraints is required to configure the genome to guide gene expression changes that drive faithful lineage progression. Loss-of-function approaches in B cell precursors show that IKAROS assembles interactions across megabase distances in preparation for lymphoid development. Interactions emanating from IKAROS-bound enhancers override CTCF-imposed boundaries to assemble lineage-specific regulatory units built on a backbone of smaller invariant topological domains. Gain of function in epithelial cells confirms IKAROS' ability to reconfigure chromatin architecture at multiple scales. Although the compaction of the Igκ locus required for genome editing represents a function of IKAROS unique to lymphocytes, the more general function to preconfigure the genome to support lineage-specific gene expression and suppress activation of extra-lineage genes provides a paradigm for lineage restriction.
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Affiliation(s)
- Yeguang Hu
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Daniela Salgado Figueroa
- Centers for Autoimmunity, Inflammation and Cancer Immunotherapy, La Jolla Institute for Immunology, La Jolla, CA 92037, USA; Bioinformatics and Systems Biology Program, La Jolla, CA, USA
| | - Zhihong Zhang
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Margaret Veselits
- Gwen Knapp Center for Lupus and Immunology Research, Section of Rheumatology, Department of Medicine, The University of Chicago, Chicago, IL 60637, USA
| | - Sourya Bhattacharyya
- Centers for Autoimmunity, Inflammation and Cancer Immunotherapy, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Mariko Kashiwagi
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Marcus R Clark
- Gwen Knapp Center for Lupus and Immunology Research, Section of Rheumatology, Department of Medicine, The University of Chicago, Chicago, IL 60637, USA
| | - Bruce A Morgan
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Ferhat Ay
- Centers for Autoimmunity, Inflammation and Cancer Immunotherapy, La Jolla Institute for Immunology, La Jolla, CA 92037, USA; Bioinformatics and Systems Biology Program, La Jolla, CA, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Katia Georgopoulos
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA.
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39
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Badia-I-Mompel P, Wessels L, Müller-Dott S, Trimbour R, Ramirez Flores RO, Argelaguet R, Saez-Rodriguez J. Gene regulatory network inference in the era of single-cell multi-omics. Nat Rev Genet 2023; 24:739-754. [PMID: 37365273 DOI: 10.1038/s41576-023-00618-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/12/2023] [Indexed: 06/28/2023]
Abstract
The interplay between chromatin, transcription factors and genes generates complex regulatory circuits that can be represented as gene regulatory networks (GRNs). The study of GRNs is useful to understand how cellular identity is established, maintained and disrupted in disease. GRNs can be inferred from experimental data - historically, bulk omics data - and/or from the literature. The advent of single-cell multi-omics technologies has led to the development of novel computational methods that leverage genomic, transcriptomic and chromatin accessibility information to infer GRNs at an unprecedented resolution. Here, we review the key principles of inferring GRNs that encompass transcription factor-gene interactions from transcriptomics and chromatin accessibility data. We focus on the comparison and classification of methods that use single-cell multimodal data. We highlight challenges in GRN inference, in particular with respect to benchmarking, and potential further developments using additional data modalities.
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Affiliation(s)
- Pau Badia-I-Mompel
- Heidelberg University, Faculty of Medicine, Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
| | - Lorna Wessels
- Heidelberg University, Faculty of Medicine, Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
- Department of Vascular Biology and Tumor Angiogenesis, European Center for Angioscience, Medical Faculty, MannHeim Heidelberg University, Mannheim, Germany
| | - Sophia Müller-Dott
- Heidelberg University, Faculty of Medicine, Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
| | - Rémi Trimbour
- Heidelberg University, Faculty of Medicine, Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
- Institut Pasteur, Université Paris Cité, CNRS UMR 3738, Machine Learning for Integrative Genomics Group, Paris, France
| | - Ricardo O Ramirez Flores
- Heidelberg University, Faculty of Medicine, Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany
| | | | - Julio Saez-Rodriguez
- Heidelberg University, Faculty of Medicine, Heidelberg University Hospital, Institute for Computational Biomedicine, Bioquant, Heidelberg, Germany.
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40
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Mielczarek O, Rogers CH, Zhan Y, Matheson LS, Stubbington MJT, Schoenfelder S, Bolland DJ, Javierre BM, Wingett SW, Várnai C, Segonds-Pichon A, Conn SJ, Krueger F, Andrews S, Fraser P, Giorgetti L, Corcoran AE. Intra- and interchromosomal contact mapping reveals the Igh locus has extensive conformational heterogeneity and interacts with B-lineage genes. Cell Rep 2023; 42:113074. [PMID: 37676766 PMCID: PMC10548092 DOI: 10.1016/j.celrep.2023.113074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/28/2023] [Accepted: 08/18/2023] [Indexed: 09/09/2023] Open
Abstract
To produce a diverse antibody repertoire, immunoglobulin heavy-chain (Igh) loci undergo large-scale alterations in structure to facilitate juxtaposition and recombination of spatially separated variable (VH), diversity (DH), and joining (JH) genes. These chromosomal alterations are poorly understood. Uncovering their patterns shows how chromosome dynamics underpins antibody diversity. Using tiled Capture Hi-C, we produce a comprehensive map of chromatin interactions throughout the 2.8-Mb Igh locus in progenitor B cells. We find that the Igh locus folds into semi-rigid subdomains and undergoes flexible looping of the VH genes to its 3' end, reconciling two views of locus organization. Deconvolution of single Igh locus conformations using polymer simulations identifies thousands of different structures. This heterogeneity may underpin the diversity of V(D)J recombination events. All three immunoglobulin loci also participate in a highly specific, developmentally regulated network of interchromosomal interactions with genes encoding B cell-lineage factors. This suggests a model of interchromosomal coordination of B cell development.
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Affiliation(s)
- Olga Mielczarek
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Carolyn H Rogers
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Yinxiu Zhan
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Louise S Matheson
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Michael J T Stubbington
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Stefan Schoenfelder
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Daniel J Bolland
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Biola M Javierre
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Steven W Wingett
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Csilla Várnai
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Anne Segonds-Pichon
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Simon J Conn
- Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Felix Krueger
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Simon Andrews
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Peter Fraser
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Luca Giorgetti
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Anne E Corcoran
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK.
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41
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Hristov BH, Noble WS, Bertero A. Systematic identification of inter-chromosomal interaction networks supports the existence of RNA factories. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.21.558852. [PMID: 37790381 PMCID: PMC10542540 DOI: 10.1101/2023.09.21.558852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Most studies of genome organization have focused on intra-chromosomal (cis) contacts because they harbor key features such as DNA loops and topologically associating domains. Inter-chromosomal (trans) contacts have received much less attention, and tools for interrogating potential biologically relevant trans structures are lacking. Here, we develop a computational framework to identify sets of loci that jointly interact in trans from Hi-C data. This method, trans-C, initiates probabilistic random walks with restarts from a set of seed loci to traverse an input Hi-C contact network, thereby identifying sets of trans-contacting loci. We validate trans-C in three increasingly complex models of established trans contacts: the Plasmodium falciparum var genes, the mouse olfactory receptor "Greek islands", and the human RBM20 cardiac splicing factory. We then apply trans-C to systematically test the hypothesis that genes co-regulated by the same trans-acting element (i.e., a transcription or splicing factor) co-localize in three dimensions to form "RNA factories" that maximize the efficiency and accuracy of RNA biogenesis. We find that many loci with multiple binding sites of the same transcription factor interact with one another in trans, especially those bound by transcription factors with intrinsically disordered domains. Similarly, clustered binding of a subset of RNA binding proteins correlates with trans interaction of the encoding loci. These findings support the existence of trans interacting chromatin domains (TIDs) driven by RNA biogenesis. Trans-C provides an efficient computational framework for studying these and other types of trans interactions, empowering studies of a poorly understood aspect of genome architecture.
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Affiliation(s)
| | - William Stafford Noble
- Department of Genome Sciences, University of Washington, Seattle, USA
- Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, USA
| | - Alessandro Bertero
- Molecular Biotechnology Center “Guido Tarone”, Dept. of Molecular Biotechnology and Health Sciences, University of Turin, Torino, Italy
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42
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Bashkirova EV, Klimpert N, Monahan K, Campbell CE, Osinski JM, Tan L, Schieren I, Pourmorady A, Stecky B, Barnea G, Xie XS, Abdus-Saboor I, Shykind B, Jones-Marlin B, Gronostajski RM, Fleischmann A, Lomvardas S. Opposing, spatially-determined epigenetic forces impose restrictions on stochastic olfactory receptor choice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.15.532726. [PMID: 36993168 PMCID: PMC10055043 DOI: 10.1101/2023.03.15.532726] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Olfactory receptor (OR) choice represents an example of genetically hardwired stochasticity, where every olfactory neuron expresses one out of ~2000 OR alleles in a probabilistic, yet stereotypic fashion. Here, we propose that topographic restrictions in OR expression are established in neuronal progenitors by two opposing forces: polygenic transcription and genomic silencing, both of which are influenced by dorsoventral gradients of transcription factors NFIA, B, and X. Polygenic transcription of OR genes may define spatially constrained OR repertoires, among which one OR allele is selected for singular expression later in development. Heterochromatin assembly and genomic compartmentalization of OR alleles also vary across the axes of the olfactory epithelium and may preferentially eliminate ectopically expressed ORs with more dorsal expression destinations from this "privileged" repertoire. Our experiments identify early transcription as a potential "epigenetic" contributor to future developmental patterning and reveal how two spatially responsive probabilistic processes may act in concert to establish deterministic, precise, and reproducible territories of stochastic gene expression.
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Affiliation(s)
- Elizaveta V Bashkirova
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, Columbia University, New York, NY, 10032, USA
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
| | - Nell Klimpert
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, RI, USA
| | - Kevin Monahan
- Department of Biochemistry and Molecular Biology, Rutgers University, NJ, USA
| | - Christine E Campbell
- Department of Biochemistry, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA
- Genetics, Genomics, and Bioinformatics Graduate Program, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA
| | - Jason M Osinski
- Department of Biochemistry, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA
- Genetics, Genomics, and Bioinformatics Graduate Program, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA
| | - Longzhi Tan
- Department of Bioengineering, Stanford University, CA, USA
| | - Ira Schieren
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
| | - Ariel Pourmorady
- Integrated Program in Cellular, Molecular and Biomedical Studies, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, Columbia University, New York, NY, 10032, USA
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
| | - Beka Stecky
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
| | - Gilad Barnea
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, RI, USA
| | - X Sunnie Xie
- Beijing Innovation Center for Genomics, Peking University, Beijing, China
- Biomedical Pioneering Innovation Center, Peking University, Beijing, China
| | - Ishmail Abdus-Saboor
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
| | - Benjamin Shykind
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, RI, USA
| | - Bianca Jones-Marlin
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
| | - Richard M Gronostajski
- Department of Biochemistry, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA
- Genetics, Genomics, and Bioinformatics Graduate Program, University at Buffalo and New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA
| | - Alexander Fleischmann
- Department of Neuroscience, Division of Biology and Medicine and Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, RI, USA
| | - Stavros Lomvardas
- Zuckerman Mind, Brain, and Behavior Institute, Columbia University, New York, NY, 10027, USA
- Department of Biochemistry and Molecular Biophysics, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, Columbia University, New York, NY, 10032, USA
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43
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Tan L, Shi J, Moghadami S, Parasar B, Wright CP, Seo Y, Vallejo K, Cobos I, Duncan L, Chen R, Deisseroth K. Lifelong restructuring of 3D genome architecture in cerebellar granule cells. Science 2023; 381:1112-1119. [PMID: 37676945 PMCID: PMC11059189 DOI: 10.1126/science.adh3253] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 08/03/2023] [Indexed: 09/09/2023]
Abstract
The cerebellum contains most of the neurons in the human brain and exhibits distinctive modes of development and aging. In this work, by developing our single-cell three-dimensional (3D) genome assay-diploid chromosome conformation capture, or Dip-C-into population-scale (Pop-C) and virus-enriched (vDip-C) modes, we resolved the first 3D genome structures of single cerebellar cells, created life-spanning 3D genome atlases for both humans and mice, and jointly measured transcriptome and chromatin accessibility during development. We found that although the transcriptome and chromatin accessibility of cerebellar granule neurons mature in early postnatal life, 3D genome architecture gradually remodels throughout life, establishing ultra-long-range intrachromosomal contacts and specific interchromosomal contacts that are rarely seen in neurons. These results reveal unexpected evolutionarily conserved molecular processes that underlie distinctive features of neural development and aging across the mammalian life span.
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Affiliation(s)
- Longzhi Tan
- Department of Neurobiology, Stanford University, Stanford, CA, 94305
- Department of Bioengineering, Stanford University, Stanford, CA, 94305
| | - Jenny Shi
- Department of Neurobiology, Stanford University, Stanford, CA, 94305
- Department of Bioengineering, Stanford University, Stanford, CA, 94305
- Department of Chemistry, Stanford University, Stanford, CA, 94305
| | - Siavash Moghadami
- Department of Neurobiology, Stanford University, Stanford, CA, 94305
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, 94305
| | - Bibudha Parasar
- Department of Neurobiology, Stanford University, Stanford, CA, 94305
| | - Cydney P. Wright
- Department of Neurobiology, Stanford University, Stanford, CA, 94305
- Department of Biology, Stanford University, Stanford, CA, 94305
| | - Yunji Seo
- Department of Neurobiology, Stanford University, Stanford, CA, 94305
| | - Kristen Vallejo
- Department of Pathology, Stanford University, Stanford, CA, 94305
| | - Inma Cobos
- Department of Pathology, Stanford University, Stanford, CA, 94305
| | - Laramie Duncan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305
| | - Ritchie Chen
- Department of Bioengineering, Stanford University, Stanford, CA, 94305
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, CA, 94305
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305
- Howard Hughes Medical Institute, Stanford, CA, 94305
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44
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Chen Q, Li H, Yang X. Total-Activity Conservation Analysis and Design of Boolean Networks. IEEE TRANSACTIONS ON CYBERNETICS 2023; 53:5667-5676. [PMID: 35417375 DOI: 10.1109/tcyb.2022.3163608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The law of conservation of mass, represented in Boolean networks (BNs) as total-activity conservation, is one of the typical properties of biological networks. This article analyzes the total-activity conservation of BNs based on the algebraic state-space representation (ASSR) approach. First, the total-activity-conservative matrix is defined and a matrix-based criterion is proposed to verify the total-activity conservation of BNs. Meanwhile, when function perturbation is considered, robust total-activity conservation is investigated. Second, by means of the pseudo-Boolean function generated by total-activity conservation, a constructive design procedure of the Boolean dynamics is given to achieve the total-activity conservation. Third, the total-activity conservation of switched Boolean networks (SBNs) under arbitrary switching signal is studied, which together with network aggregation achieves the total-activity conservation of large-scale BNs.
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45
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Mohana G, Dorier J, Li X, Mouginot M, Smith RC, Malek H, Leleu M, Rodriguez D, Khadka J, Rosa P, Cousin P, Iseli C, Restrepo S, Guex N, McCabe BD, Jankowski A, Levine MS, Gambetta MC. Chromosome-level organization of the regulatory genome in the Drosophila nervous system. Cell 2023; 186:3826-3844.e26. [PMID: 37536338 PMCID: PMC10529364 DOI: 10.1016/j.cell.2023.07.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 03/31/2023] [Accepted: 07/06/2023] [Indexed: 08/05/2023]
Abstract
Previous studies have identified topologically associating domains (TADs) as basic units of genome organization. We present evidence of a previously unreported level of genome folding, where distant TAD pairs, megabases apart, interact to form meta-domains. Within meta-domains, gene promoters and structural intergenic elements present in distant TADs are specifically paired. The associated genes encode neuronal determinants, including those engaged in axonal guidance and adhesion. These long-range associations occur in a large fraction of neurons but support transcription in only a subset of neurons. Meta-domains are formed by diverse transcription factors that are able to pair over long and flexible distances. We present evidence that two such factors, GAF and CTCF, play direct roles in this process. The relative simplicity of higher-order meta-domain interactions in Drosophila, compared with those previously described in mammals, allowed the demonstration that genomes can fold into highly specialized cell-type-specific scaffolds that enable megabase-scale regulatory associations.
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Affiliation(s)
- Giriram Mohana
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Julien Dorier
- Bioinformatics Competence Center, University of Lausanne, 1015 Lausanne, Switzerland; Bioinformatics Competence Center, Swiss Federal Institute of Technology Lausanne, 1015 Lausanne, Switzerland
| | - Xiao Li
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Marion Mouginot
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Rebecca C Smith
- Brain Mind Institute, Swiss Federal Institute of Technology Lausanne, 1015 Lausanne, Switzerland
| | - Héléna Malek
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Marion Leleu
- Bioinformatics Competence Center, University of Lausanne, 1015 Lausanne, Switzerland; Bioinformatics Competence Center, Swiss Federal Institute of Technology Lausanne, 1015 Lausanne, Switzerland
| | - Daniel Rodriguez
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Jenisha Khadka
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Patrycja Rosa
- Faculty of Mathematics, Informatics and Mechanics, University of Warsaw, 02-097 Warsaw, Poland
| | - Pascal Cousin
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Christian Iseli
- Bioinformatics Competence Center, University of Lausanne, 1015 Lausanne, Switzerland; Bioinformatics Competence Center, Swiss Federal Institute of Technology Lausanne, 1015 Lausanne, Switzerland
| | - Simon Restrepo
- Arcoris bio AG, Lüssirainstrasse 52, 6300 Zug, Switzerland
| | - Nicolas Guex
- Bioinformatics Competence Center, University of Lausanne, 1015 Lausanne, Switzerland; Bioinformatics Competence Center, Swiss Federal Institute of Technology Lausanne, 1015 Lausanne, Switzerland
| | - Brian D McCabe
- Brain Mind Institute, Swiss Federal Institute of Technology Lausanne, 1015 Lausanne, Switzerland
| | - Aleksander Jankowski
- Faculty of Mathematics, Informatics and Mechanics, University of Warsaw, 02-097 Warsaw, Poland.
| | - Michael S Levine
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
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46
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Brovkina MV, Chapman MA, Holding ML, Clowney EJ. Emergence and influence of sequence bias in evolutionarily malleable, mammalian tandem arrays. BMC Biol 2023; 21:179. [PMID: 37612705 PMCID: PMC10463633 DOI: 10.1186/s12915-023-01673-4] [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: 04/25/2023] [Accepted: 08/01/2023] [Indexed: 08/25/2023] Open
Abstract
BACKGROUND The radiation of mammals at the extinction of the dinosaurs produced a plethora of new forms-as diverse as bats, dolphins, and elephants-in only 10-20 million years. Behind the scenes, adaptation to new niches is accompanied by extensive innovation in large families of genes that allow animals to contact the environment, including chemosensors, xenobiotic enzymes, and immune and barrier proteins. Genes in these "outward-looking" families are allelically diverse among humans and exhibit tissue-specific and sometimes stochastic expression. RESULTS Here, we show that these tandem arrays of outward-looking genes occupy AT-biased isochores and comprise the "tissue-specific" gene class that lack CpG islands in their promoters. Models of mammalian genome evolution have not incorporated the sharply different functions and transcriptional patterns of genes in AT- versus GC-biased regions. To examine the relationship between gene family expansion, sequence content, and allelic diversity, we use population genetic data and comparative analysis. First, we find that AT bias can emerge during evolutionary expansion of gene families in cis. Second, human genes in AT-biased isochores or with GC-poor promoters experience relatively low rates of de novo point mutation today but are enriched for non-synonymous variants. Finally, we find that isochores containing gene clusters exhibit low rates of recombination. CONCLUSIONS Our analyses suggest that tolerance of non-synonymous variation and low recombination are two forces that have produced the depletion of GC bases in outward-facing gene arrays. In turn, high AT content exerts a profound effect on their chromatin organization and transcriptional regulation.
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Affiliation(s)
- Margarita V Brovkina
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Margaret A Chapman
- Neurosciences Graduate Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - E Josephine Clowney
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA.
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Bond ML, Davis ES, Quiroga IY, Dey A, Kiran M, Love MI, Won H, Phanstiel DH. Chromatin loop dynamics during cellular differentiation are associated with changes to both anchor and internal regulatory features. Genome Res 2023; 33:1258-1268. [PMID: 37699658 PMCID: PMC10547260 DOI: 10.1101/gr.277397.122] [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: 10/31/2022] [Accepted: 07/07/2023] [Indexed: 09/14/2023]
Abstract
Three-dimensional (3D) chromatin structure has been shown to play a role in regulating gene transcription during biological transitions. Although our understanding of loop formation and maintenance is rapidly improving, much less is known about the mechanisms driving changes in looping and the impact of differential looping on gene transcription. One limitation has been a lack of well-powered differential looping data sets. To address this, we conducted a deeply sequenced Hi-C time course of megakaryocyte development comprising four biological replicates and 6 billion reads per time point. Statistical analysis revealed 1503 differential loops. Gained loop anchors were enriched for AP-1 occupancy and were characterized by large increases in histone H3K27ac (over 11-fold) but relatively small increases in CTCF and RAD21 binding (1.26- and 1.23-fold, respectively). Linear modeling revealed that changes in histone H3K27ac, chromatin accessibility, and JUN binding were better correlated with changes in looping than RAD21 and almost as well correlated as CTCF. Changes to epigenetic features between-rather than at-boundaries were highly predictive of changes in looping. Together these data suggest that although CTCF and RAD21 may be the core machinery dictating where loops form, other features (both at the anchors and within the loop boundaries) may play a larger role than previously anticipated in determining the relative loop strength across cell types and conditions.
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Affiliation(s)
- Marielle L Bond
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Eric S Davis
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Ivana Y Quiroga
- Thurston Arthritis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Anubha Dey
- Department of Systems and Computational Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Manjari Kiran
- Department of Systems and Computational Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Michael I Love
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514, USA
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Hyejung Won
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514, USA;
- Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Douglas H Phanstiel
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA;
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Thurston Arthritis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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48
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Zhao Z, Parra OP, Musella F, Scrutton-Alvarado N, Fujita SI, Alber F, Yang Y, Yamada T. Mega-Enhancer Bodies Organize Neuronal Long Genes in the Cerebellum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.19.549737. [PMID: 37503219 PMCID: PMC10370079 DOI: 10.1101/2023.07.19.549737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Dynamic regulation of gene expression plays a key role in establishing the diverse neuronal cell types in the brain. Recent findings in genome biology suggest that three-dimensional (3D) genome organization has important, but mechanistically poorly understood functions in gene transcription. Beyond local genomic interactions between promoters and enhancers, we find that cerebellar granule neurons undergoing differentiation in vivo exhibit striking increases in long-distance genomic interactions between transcriptionally active genomic loci, which are separated by tens of megabases within a chromosome or located on different chromosomes. Among these interactions, we identify a nuclear subcompartment enriched for near-megabase long enhancers and their associated neuronal long genes encoding synaptic or signaling proteins. Neuronal long genes are differentially recruited to this enhancer-dense subcompartment to help shape the transcriptional identities of granule neuron subtypes in the cerebellum. SPRITE analyses of higher-order genomic interactions, together with IGM-based 3D genome modeling and imaging approaches, reveal that the enhancer-dense subcompartment forms prominent nuclear structures, which we term mega-enhancer bodies. These novel nuclear bodies reside in the nuclear periphery, away from other transcriptionally active structures, including nuclear speckles located in the nuclear interior. Together, our findings define additional layers of higher-order 3D genome organization closely linked to neuronal maturation and identity in the brain.
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49
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Schmid CM, Gregor A, Costain G, Morel CF, Massingham L, Schwab J, Quélin C, Faoucher M, Kaplan J, Procopio R, Saunders CJ, Cohen ASA, Lemire G, Sacharow S, O'Donnell-Luria A, Segal RJ, Kianmahd Shamshoni J, Schweitzer D, Ebrahimi-Fakhari D, Monaghan K, Palculict TB, Napier MP, Tao A, Isidor B, Moradkhani K, Reis A, Sticht H, Chung WK, Zweier C. LHX2 haploinsufficiency causes a variable neurodevelopmental disorder. Genet Med 2023; 25:100839. [PMID: 37057675 DOI: 10.1016/j.gim.2023.100839] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 04/15/2023] Open
Abstract
PURPOSE LHX2 encodes the LIM homeobox 2 transcription factor (LHX2), which is highly expressed in brain and well conserved across species, but it has not been clearly linked to neurodevelopmental disorders (NDDs) to date. METHODS Through international collaboration, we identified 19 individuals from 18 families with variable neurodevelopmental phenotypes, carrying a small chromosomal deletion, likely gene-disrupting or missense variants in LHX2. Functional consequences of missense variants were investigated in cellular systems. RESULTS Affected individuals presented with developmental and/or behavioral abnormalities, autism spectrum disorder, variable intellectual disability, and microcephaly. We observed nucleolar accumulation for 2 missense variants located within the DNA-binding HOX domain, impaired interaction with co-factor LDB1 for another variant located in the protein-protein interaction-mediating LIM domain, and impaired transcriptional activation by luciferase assay for 4 missense variants. CONCLUSION We implicate LHX2 haploinsufficiency by deletion and likely gene-disrupting variants as causative for a variable NDD. Our findings suggest a loss-of-function mechanism also for likely pathogenic LHX2 missense variants. Together, our observations underscore the importance of LHX2 in the nervous system and for variable neurodevelopmental phenotypes.
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Affiliation(s)
- Cosima M Schmid
- Department of Human Genetics, Inselspital Bern, University of Bern, Bern, Switzerland; Department for Biomedical Research, University of Bern, Bern, Switzerland
| | - Anne Gregor
- Department of Human Genetics, Inselspital Bern, University of Bern, Bern, Switzerland; Department for Biomedical Research, University of Bern, Bern, Switzerland; Bern Center for Precision Medicine (BCPM), University of Bern, Bern, Switzerland
| | - Gregory Costain
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada; Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
| | - Chantal F Morel
- The Fred A. Litwin Family Centre in Genetic Medicine, University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada; Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Lauren Massingham
- Division of Human Genetics, Department of Pediatrics, Warren Alpert Medical School of Brown University, Hasbro Children's Hospital/Rhode Island Hospital, Providence, RI
| | - Jennifer Schwab
- Division of Human Genetics, Department of Pediatrics, Warren Alpert Medical School of Brown University, Hasbro Children's Hospital/Rhode Island Hospital, Providence, RI
| | - Chloé Quélin
- Clinical Genetics Department, CHU Hôspital Sud, Rennes, France
| | - Marie Faoucher
- Service de Génétique Moléculaire et Génomique, CHU, Rennes, France; Univ Rennes, CNRS, IGDR, UMR 6290, Rennes, France
| | - Julie Kaplan
- Division of Genetics, Department of Pediatrics, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE
| | - Rebecca Procopio
- Division of Genetics, Department of Pediatrics, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE
| | - Carol J Saunders
- Genomic Medicine Center, Department of Pathology and Laboratory Medicine, Children's Mercy Kansas City, Kansas City, MO; University of Missouri-Kansas City School of Medicine, Kansas City, MO
| | - Ana S A Cohen
- Genomic Medicine Center, Department of Pathology and Laboratory Medicine, Children's Mercy Kansas City, Kansas City, MO; University of Missouri-Kansas City School of Medicine, Kansas City, MO
| | - Gabrielle Lemire
- Broad Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA; Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Stephanie Sacharow
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Anne O'Donnell-Luria
- Broad Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA; Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Ranit Jaron Segal
- Schneider Children's Medical Center of Israel, Petach Tikvah, Israel
| | - Jessica Kianmahd Shamshoni
- Division of Medical Genetics, Department of Pediatrics, David Geffen School of Medicine, UCLA, Los Angeles, CA
| | - Daniela Schweitzer
- Division of Medical Genetics, Department of Pediatrics, David Geffen School of Medicine, UCLA, Los Angeles, CA
| | - Darius Ebrahimi-Fakhari
- Movement Disorders Program, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | | | | | | | - Alice Tao
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY
| | | | | | - André Reis
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany; Centre for Rare Diseases Erlangen (ZSEER), University Hospital Erlangen, Friedrich-Alexander University of Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Heinrich Sticht
- Institut für Biochemie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Wendy K Chung
- Departments of Pediatrics and Medicine, Columbia University, New York, NY
| | - Christiane Zweier
- Department of Human Genetics, Inselspital Bern, University of Bern, Bern, Switzerland; Department for Biomedical Research, University of Bern, Bern, Switzerland; Bern Center for Precision Medicine (BCPM), University of Bern, Bern, Switzerland.
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50
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Rappoport N, Chomsky E, Nagano T, Seibert C, Lubling Y, Baran Y, Lifshitz A, Leung W, Mukamel Z, Shamir R, Fraser P, Tanay A. Single cell Hi-C identifies plastic chromosome conformations underlying the gastrulation enhancer landscape. Nat Commun 2023; 14:3844. [PMID: 37386027 PMCID: PMC10310791 DOI: 10.1038/s41467-023-39549-4] [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: 11/27/2022] [Accepted: 06/19/2023] [Indexed: 07/01/2023] Open
Abstract
Embryonic development involves massive proliferation and differentiation of cell lineages. This must be supported by chromosome replication and epigenetic reprogramming, but how proliferation and cell fate acquisition are balanced in this process is not well understood. Here we use single cell Hi-C to map chromosomal conformations in post-gastrulation mouse embryo cells and study their distributions and correlations with matching embryonic transcriptional atlases. We find that embryonic chromosomes show a remarkably strong cell cycle signature. Despite that, replication timing, chromosome compartment structure, topological associated domains (TADs) and promoter-enhancer contacts are shown to be variable between distinct epigenetic states. About 10% of the nuclei are identified as primitive erythrocytes, showing exceptionally compact and organized compartment structure. The remaining cells are broadly associated with ectoderm and mesoderm identities, showing only mild differentiation of TADs and compartment structures, but more specific localized contacts in hundreds of ectoderm and mesoderm promoter-enhancer pairs. The data suggest that while fully committed embryonic lineages can rapidly acquire specific chromosomal conformations, most embryonic cells are showing plastic signatures driven by complex and intermixed enhancer landscapes.
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Affiliation(s)
- Nimrod Rappoport
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
- The Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv, Israel
| | - Elad Chomsky
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Takashi Nagano
- Laboratory for Nuclear Dynamics, Institute for Protein Research, Osaka University, Osaka, Japan
- Nuclear Dynamics Programme, The Babraham Institute, Cambridge, UK
| | - Charlie Seibert
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Yaniv Lubling
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Yael Baran
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Aviezer Lifshitz
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Wing Leung
- Laboratory for Nuclear Dynamics, Institute for Protein Research, Osaka University, Osaka, Japan
- Nuclear Dynamics Programme, The Babraham Institute, Cambridge, UK
| | - Zohar Mukamel
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Ron Shamir
- The Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv, Israel
| | - Peter Fraser
- Nuclear Dynamics Programme, The Babraham Institute, Cambridge, UK.
- Department of Biological Science, Florida State University, Tallahassee, FL, USA.
| | - Amos Tanay
- Department of Computer Science and Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
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