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Khandia R, Garg R, Pandey MK, Khan AA, Dhanda SK, Malik A, Gurjar P. Determination of codon pattern and evolutionary forces acting on genes linked to inflammatory bowel disease. Int J Biol Macromol 2024; 278:134480. [PMID: 39116987 DOI: 10.1016/j.ijbiomac.2024.134480] [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: 04/01/2024] [Revised: 06/25/2024] [Accepted: 07/31/2024] [Indexed: 08/10/2024]
Abstract
Inflammatory bowel disease (IBD) is an inflammatory disorder of the gastrointestinal tract. The present study attempted to understand the codon usage preferences in genes associated with IBD progression. Compositional analysis, codon usage bias (CUB), Relative synonymous codon usage (RSCU), RNA structure, and expression analysis were performed to obtain a comprehensive picture of codon usage in IBD genes. Compositional analysis of 62 IBD-associated genes revealed that G and T are the most and least abundant nucleotides, respectively. ApG, CpA, and TpG dinucleotides were overrepresented or randomly used, while ApC, CpG, GpT, and TpA dinucleotides were either underrepresented or randomly used in genes related to IBD. The codons influencing the codon usage the most in IBD genes were CGC and AGG. A comparison of codon usage between IBD, and pancreatitis (non-IBD inflammatory disease) indicated that only codon CTG codon usage was significantly different between IBD and pancreatitis. At the same time, there were codons ATA, ACA, CGT, CAA, GTA, CCT, ATT, GCT, CGG, TTG, and CAG for whom codon usage was significantly different for IBD and housekeeping gene sets. The results suggest similar codon usage in at least two inflammatory disorders, IBD and pancreatitis. The analysis helps understand the codon biology, factors affecting gene expression of IBD-associated genes, and the evolution of these genes. The study helps reveal the molecular patterns associated with IBD.
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Affiliation(s)
- Rekha Khandia
- Department of Biochemistry and Genetics, Barkatullah University, Bhopal 462026, MP, India.
| | - Rajkumar Garg
- Department of Biosciences, Barkatullah University, Bhopal 462026, MP, India
| | - Megha Katare Pandey
- Translational Medicine Center, All India Institute of Medical Sciences, Bhopal 462020, MP, India.
| | - Azmat Ali Khan
- Pharmaceutical Biotechnology Laboratory, Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Sandeep Kumar Dhanda
- Department of Oncology, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Abdul Malik
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Pankaj Gurjar
- Centre for Global Health Research, Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India; Department of Science and Engineering, Novel Global Community Educational Foundation, Hebersham, Australia.
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2
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Lin H, Cui Z, E T, Xu H, Wang D, Wang P, Ruan X, Liu L, Xue Y. M6A-methylated circPOLR2B forms an R-loop and regulates the biological behavior of glioma stem cells through positive feedback loops. Cell Death Dis 2024; 15:554. [PMID: 39090090 PMCID: PMC11294345 DOI: 10.1038/s41419-024-06946-6] [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: 02/29/2024] [Revised: 07/18/2024] [Accepted: 07/24/2024] [Indexed: 08/04/2024]
Abstract
Glioma is the most common primary brain tumor, and targeting glioma stem cells (GSCs) has become a key aspect of glioma treatment. In this study, we discovered a molecular network in which circRNA forms an R-loop structure with its parental gene to regulate the biological behavior of GSCs. Genes with abnormal expression in GSCs were screened using RNA-seq and circRNA microarray analyses. The study results showed that high expression of YTHDC1 in GSCs promoted the transportation of N6-methyladenosine (m6A)-modified circPOLR2B from the nucleus to the cytoplasm. Decreased circPOLR2B levels in the nucleus resulted in fewer R-loop structures formed with its parental gene POLR2B. This reduction in R-loop structures relieved the inhibitory effect on POLR2B transcription and upregulated PBX1 expression through alternative polyadenylation (APA) action, thereby promoting the malignant biological behavior of GSCs. Knockdown of YTHDC1, POLR2B, and PBX1 reduced xenograft tumor volume and prolonged the survival of nude mice. The YTHDC1/circPOLR2B/POLR2B/PBX1 axis plays a regulatory role in the biological behavior of GSCs, offering potential targets and novel strategies for the treatment of glioma.
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Affiliation(s)
- Hongda Lin
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Liaoning Medical Surgery and Rehabilitation Robot Technology Engineering Research Center, Shenyang, China
| | - Zheng Cui
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Liaoning Medical Surgery and Rehabilitation Robot Technology Engineering Research Center, Shenyang, China
| | - Tiange E
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Liaoning Medical Surgery and Rehabilitation Robot Technology Engineering Research Center, Shenyang, China
| | - Hailing Xu
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Liaoning Medical Surgery and Rehabilitation Robot Technology Engineering Research Center, Shenyang, China
| | - Di Wang
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Liaoning Medical Surgery and Rehabilitation Robot Technology Engineering Research Center, Shenyang, China
| | - Ping Wang
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China
| | - Xuelei Ruan
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China
| | - Libo Liu
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China
| | - Yixue Xue
- Key Laboratory of Neuro-oncology in Liaoning Province, Shenyang, China.
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China.
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3
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Xu W, Liu X, Li J, Sun C, Chen L, Zhou J, Li K, Li Q, Meng A, Sun Q. ULI-ssDRIP-seq revealed R-loop dynamics during vertebrate early embryogenesis. CELL INSIGHT 2024; 3:100179. [PMID: 38974143 PMCID: PMC11225018 DOI: 10.1016/j.cellin.2024.100179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/29/2024] [Accepted: 05/29/2024] [Indexed: 07/09/2024]
Abstract
R-loop, a chromatin structure containing one RNA:DNA hybrid and one unpaired single-stranded DNA, plays multiple biological roles. However, due to technical limitations, the landscapes and potential functions of R-loops during embryogenesis remain elusive. Here, we developed a quantitative and high-resolution ultra-low input R-loop profiling method, named ULI-ssDRIP-seq, which can map global R-loops with as few as 1000 cells. By using ULI-ssDRIP-seq, we reveal the R-loop dynamics in the zebrafish from gametes to early embryos. In oocytes, the R-loop level is relatively low in most regions of the nuclear genome, except maternal-inherited rDNA and mitochondrial genome. The correlation between R-loop and CG methylation dynamics during early development is relatively weak. Furthermore, either up- or down-regulation of global R-loops by knockdown or overexpression of RNase H1 causes a delay of embryonic development with dramatic expression changes in zygotic and maternal genes. This study provides comprehensive R-loop landscapes during early vertebrate embryogenesis and demonstrates the implication of R-loops in embryonic development.
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Affiliation(s)
- Wei Xu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Xin Liu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Jinjin Li
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Changbin Sun
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Luxi Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Jincong Zhou
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Kuan Li
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Qin Li
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Anming Meng
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Qianwen Sun
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
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4
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Luna R, Gómez-González B, Aguilera A. RNA biogenesis and RNA metabolism factors as R-loop suppressors: a hidden role in genome integrity. Genes Dev 2024; 38:504-527. [PMID: 38986581 PMCID: PMC11293400 DOI: 10.1101/gad.351853.124] [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: 07/12/2024]
Abstract
Genome integrity relies on the accuracy of DNA metabolism, but as appreciated for more than four decades, transcription enhances mutation and recombination frequencies. More recent research provided evidence for a previously unforeseen link between RNA and DNA metabolism, which is often related to the accumulation of DNA-RNA hybrids and R-loops. In addition to physiological roles, R-loops interfere with DNA replication and repair, providing a molecular scenario for the origin of genome instability. Here, we review current knowledge on the multiple RNA factors that prevent or resolve R-loops and consequent transcription-replication conflicts and thus act as modulators of genome dynamics.
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Affiliation(s)
- Rosa Luna
- Andalusian Center of Molecular Biology and Regenerative Medicine (CABIMER), Universidad de Sevilla-Spanish National Research Council (CSIC), 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Belén Gómez-González
- Andalusian Center of Molecular Biology and Regenerative Medicine (CABIMER), Universidad de Sevilla-Spanish National Research Council (CSIC), 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Andrés Aguilera
- Andalusian Center of Molecular Biology and Regenerative Medicine (CABIMER), Universidad de Sevilla-Spanish National Research Council (CSIC), 41092 Seville, Spain;
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
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Kannan A, Gangadharan Leela S, Branzei D, Gangwani L. Role of senataxin in R-loop-mediated neurodegeneration. Brain Commun 2024; 6:fcae239. [PMID: 39070547 PMCID: PMC11277865 DOI: 10.1093/braincomms/fcae239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 06/14/2024] [Accepted: 07/13/2024] [Indexed: 07/30/2024] Open
Abstract
Senataxin is an RNA:DNA helicase that plays an important role in the resolution of RNA:DNA hybrids (R-loops) formed during transcription. R-loops are involved in the regulation of biological processes such as immunoglobulin class switching, gene expression and DNA repair. Excessive accumulation of R-loops results in DNA damage and loss of genomic integrity. Senataxin is critical for maintaining optimal levels of R-loops to prevent DNA damage and acts as a genome guardian. Within the nucleus, senataxin interacts with various RNA processing factors and DNA damage response and repair proteins. Senataxin interactors include survival motor neuron and zinc finger protein 1, with whom it co-localizes in sub-nuclear bodies. Despite its ubiquitous expression, mutations in senataxin specifically affect neurons and result in distinct neurodegenerative diseases such as amyotrophic lateral sclerosis type 4 and ataxia with oculomotor apraxia type 2, which are attributed to the gain-of-function and the loss-of-function mutations in senataxin, respectively. In addition, low levels of senataxin (loss-of-function) in spinal muscular atrophy result in the accumulation of R-loops causing DNA damage and motor neuron degeneration. Senataxin may play multiple functions in diverse cellular processes; however, its emerging role in R-loop resolution and maintenance of genomic integrity is gaining attention in the field of neurodegenerative diseases. In this review, we highlight the role of senataxin in R-loop resolution and its potential as a therapeutic target to treat neurodegenerative diseases.
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Affiliation(s)
| | - Shyni Gangadharan Leela
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Dana Branzei
- The AIRC Institute of Molecular Oncology Foundation, IFOM ETS, Milan 20139, Italy
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Pavia 27100, Italy
| | - Laxman Gangwani
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
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R P, Rakshit S, Shanmugam G, George M, Sarkar K. Wiskott Aldrich syndrome protein (WASp)-deficient Th1 cells promote R-loop-driven transcriptional insufficiency and transcription-coupled nucleotide excision repair factor (TC-NER)-driven genome-instability in the pathogenesis of T cell acute lymphoblastic leukemia. Clin Immunol 2024; 263:110204. [PMID: 38582251 DOI: 10.1016/j.clim.2024.110204] [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: 01/25/2024] [Revised: 03/21/2024] [Accepted: 04/01/2024] [Indexed: 04/08/2024]
Abstract
BACKGROUND T-ALL is an aggressive hematological tumor that develops as the result of a multi-step oncogenic process which causes expansion of hematopoietic progenitors that are primed for T cell development to undergo malignant transformation and growth. Even though first-line therapy has a significant response rate, 40% of adult patients and 20% of pediatric patients will relapse. Therefore, there is an unmet need for treatment for relapsed/refractory T-ALL to develop potential targeted therapies. METHODS Pediatric T-ALL patient derived T cells were grown under either nonskewingTh0 or Th1-skewing conditions to further process for ChIP-qPCR, RDIP-qPCR and other RT-PCR assays. Endogenous WASp was knocked out using CRISPR-Cas9 and was confirmed using flow cytometry and western blotting. LC-MS/MS was performed to find out proteomic dataset of WASp-interactors generated from Th1-skewed, human primary Th-cells. DNA-damage was assessed by immunofluorescence confocal-imaging and single-cell gel electrophoresis (comet assay). Overexpression of RNaseH1 was also done to restore normal Th1-transcription in WASp-deficient Th1-skewed cells. RESULTS We discovered that nuclear-WASp is required for suppressing R-loop production (RNA/DNA-hybrids) at Th1-network genes by ribonucleaseH2 (RNH2) and topoisomerase1. Nuclear-WASp is associated with the factors involved in preventing and dissolving R-loops in Th1 cells. In nuclear- WASp-reduced malignant Th1-cells, R-loops accumulate in vivo and are processed into DNA-breaks by transcription-coupled-nucleotide-excision repair (TC-NER). Several epigenetic modifications were also found to be involved at Th1 gene locus which are responsible for active/repressive marks of particular genes. By demonstrating WASp as a physiologic regulator of programmed versus unprogrammed R-loops, we suggest that the transcriptional role of WASp in vivo extends also to prevent transcription-linked DNA damage during malignancy and through modification of epigenetic dysregulations. CONCLUSION Our findings present a provocative possibility of resetting R-loops as a therapeutic intervention to correct both immune deficiency and malignancy in T-cell acute lymphoblastic leukemia patients and a novel role of WASp in the epigenetic regulation of T helper cell differentiation in T-ALL patients, anticipating WASp's requirement for the suppression of T-ALL progression.
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Affiliation(s)
- Pradeep R
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Sudeshna Rakshit
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Geetha Shanmugam
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India
| | - Melvin George
- Department of Clinical Pharmacology, SRM Medical College Hospital and Research Centre, Kattankulathur, Tamil Nadu 603203, India
| | - Koustav Sarkar
- Department of Biotechnology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203, India.
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McShane A, Narayanan IV, Paulsen MT, Ashaka M, Blinkiewicz H, Yang NT, Magnuson B, Bedi K, Wilson TE, Ljungman M. Characterizing nascent transcription patterns of PROMPTs, eRNAs, and readthrough transcripts in the ENCODE4 deeply profiled cell lines. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.09.588612. [PMID: 38645116 PMCID: PMC11030308 DOI: 10.1101/2024.04.09.588612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Arising as co-products of canonical gene expression, transcription-associated lincRNAs, such as promoter upstream transcripts (PROMPTs), enhancer RNAs (eRNAs), and readthrough (RT) transcripts, are often regarded as byproducts of transcription, although they may be important for the expression of nearby genes. We identified regions of nascent expression of these lincRNA in 16 human cell lines using Bru-seq techniques, and found distinctly regulated patterns of PROMPT, eRNA, and RT transcription using the diverse biochemical approaches in the ENCODE4 deeply profiled cell lines collection. Transcription of these lincRNAs was influenced by sequence-specific features and the local or 3D chromatin landscape. However, these sequence and chromatin features do not describe the full spectrum of lincRNA expression variability we identify, highlighting the complexity of their regulation. This may suggest that transcription-associated lincRNAs are not merely byproducts, but rather that the transcript itself, or the act of its transcription, is important for genomic function.
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8
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Xu Y, Jiao Y, Liu C, Miao R, Liu C, Wang Y, Ma C, Liu J. R-loop and diseases: the cell cycle matters. Mol Cancer 2024; 23:84. [PMID: 38678239 PMCID: PMC11055327 DOI: 10.1186/s12943-024-02000-3] [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: 02/11/2024] [Accepted: 04/13/2024] [Indexed: 04/29/2024] Open
Abstract
The cell cycle is a crucial biological process that is involved in cell growth, development, and reproduction. It can be divided into G1, S, G2, and M phases, and each period is closely regulated to ensure the production of two similar daughter cells with the same genetic material. However, many obstacles influence the cell cycle, including the R-loop that is formed throughout this process. R-loop is a triple-stranded structure, composed of an RNA: DNA hybrid and a single DNA strand, which is ubiquitous in organisms from bacteria to mammals. The existence of the R-loop has important significance for the regulation of various physiological processes. However, aberrant accumulation of R-loop due to its limited resolving ability will be detrimental for cells. For example, DNA damage and genomic instability, caused by the R-loop, can activate checkpoints in the cell cycle, which in turn induce cell cycle arrest and cell death. At present, a growing number of factors have been proven to prevent or eliminate the accumulation of R-loop thereby avoiding DNA damage and mutations. Therefore, we need to gain detailed insight into the R-loop resolution factors at different stages of the cell cycle. In this review, we review the current knowledge of factors that play a role in resolving the R-loop at different stages of the cell cycle, as well as how mutations of these factors lead to the onset and progression of diseases.
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Affiliation(s)
- Yuqin Xu
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Yue Jiao
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Chengbin Liu
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Rui Miao
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Chunyan Liu
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Yilong Wang
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Chunming Ma
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China
| | - Jiao Liu
- School of Basic Medicine Sciences, Shandong Second Medical University, Weifang, 261053, China.
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9
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Rombaut D, Lefèvre C, Rached T, Bondu S, Letessier A, Mangione RM, Farhat B, Lesieur-Pasquier A, Castillo-Guzman D, Boussaid I, Friedrich C, Tourville A, De Carvalho M, Levavasseur F, Leduc M, Le Gall M, Battault S, Temple M, Houy A, Bouscary D, Willems L, Park S, Raynaud S, Cluzeau T, Clappier E, Fenaux P, Adès L, Margueron R, Wassef M, Alsafadi S, Chapuis N, Kosmider O, Solary E, Constantinou A, Stern MH, Droin N, Palancade B, Miotto B, Chédin F, Fontenay M. Accelerated DNA replication fork speed due to loss of R-loops in myelodysplastic syndromes with SF3B1 mutation. Nat Commun 2024; 15:3016. [PMID: 38589367 PMCID: PMC11001894 DOI: 10.1038/s41467-024-46547-7] [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: 12/07/2022] [Accepted: 02/29/2024] [Indexed: 04/10/2024] Open
Abstract
Myelodysplastic syndromes (MDS) with mutated SF3B1 gene present features including a favourable outcome distinct from MDS with mutations in other splicing factor genes SRSF2 or U2AF1. Molecular bases of these divergences are poorly understood. Here we find that SF3B1-mutated MDS show reduced R-loop formation predominating in gene bodies associated with intron retention reduction, not found in U2AF1- or SRSF2-mutated MDS. Compared to erythroblasts from SRSF2- or U2AF1-mutated patients, SF3B1-mutated erythroblasts exhibit augmented DNA synthesis, accelerated replication forks, and single-stranded DNA exposure upon differentiation. Importantly, histone deacetylase inhibition using vorinostat restores R-loop formation, slows down DNA replication forks and improves SF3B1-mutated erythroblast differentiation. In conclusion, loss of R-loops with associated DNA replication stress represents a hallmark of SF3B1-mutated MDS ineffective erythropoiesis, which could be used as a therapeutic target.
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Affiliation(s)
- David Rombaut
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
- Laboratoire d'excellence du Globule Rouge GR-Ex, Université Paris Cité, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France
| | - Carine Lefèvre
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
- Laboratoire d'excellence du Globule Rouge GR-Ex, Université Paris Cité, Paris, France
| | - Tony Rached
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Sabrina Bondu
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Anne Letessier
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
| | | | - Batoul Farhat
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Auriane Lesieur-Pasquier
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Daisy Castillo-Guzman
- Department of Molecular and Cellular Biology and Genome Center, University of California, Davis, CA, USA
| | - Ismael Boussaid
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France
| | - Chloé Friedrich
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France
| | - Aurore Tourville
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Magali De Carvalho
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Françoise Levavasseur
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Marjorie Leduc
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Platform Proteom'IC, Université Paris Cité, Institut Cochin, Paris, France
| | - Morgane Le Gall
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Platform Proteom'IC, Université Paris Cité, Institut Cochin, Paris, France
| | - Sarah Battault
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
| | - Marie Temple
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France
| | - Alexandre Houy
- Institut Curie, PSL Research University, Sorbonne University, INSERM U830, DNA repair and uveal melanoma, Equipe labellisée par la Ligue Nationale contre le Cancer, Paris, France
| | - Didier Bouscary
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Clinical Department of Hematology, Paris, France
| | - Lise Willems
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Clinical Department of Hematology, Paris, France
| | - Sophie Park
- Department of Hematology, Centre Hospitalier Universitaire, Université de Grenoble Alpes, Grenoble, France
| | - Sophie Raynaud
- Laboratory of Hematology, Université Côte d'Azur, Centre Hospitalier Universitaire, Nice, France
| | - Thomas Cluzeau
- Clinical Department of Hematology, Université Côte d'Azur, Centre Hospitalier Universitaire, Nice, France
| | - Emmanuelle Clappier
- Assistance Publique-Hôpitaux de Paris.Nord-Université Paris Cité, Saint-Louis Hospital, Laboratory of Hematology, Paris, France
| | - Pierre Fenaux
- Assistance Publique-Hôpitaux de Paris.Nord-Université Paris Cité, Saint-Louis Hospital, Service Hématologie Séniors, Paris, France
| | - Lionel Adès
- Assistance Publique-Hôpitaux de Paris.Nord-Université Paris Cité, Saint-Louis Hospital, Service Hématologie Séniors, Paris, France
| | - Raphael Margueron
- Institut Curie, Paris Sciences Lettres Research University, Sorbonne University, INSERM U934, UMR3215, Paris, France
| | - Michel Wassef
- Institut Curie, Paris Sciences Lettres Research University, Sorbonne University, INSERM U934, UMR3215, Paris, France
| | - Samar Alsafadi
- Institut Curie, PSL Research University, Sorbonne University, INSERM U830, DNA repair and uveal melanoma, Equipe labellisée par la Ligue Nationale contre le Cancer, Paris, France
| | - Nicolas Chapuis
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France
| | - Olivier Kosmider
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France
| | - Eric Solary
- Institut Gustave Roussy, INSERM 1287, Université Paris Saclay, Villejuif, France
| | - Angelos Constantinou
- Institut de Génétique Humaine, Centre National de la Recherche Scientifique, Université de Montpellier, Montpellier, France
| | - Marc-Henri Stern
- Institut Curie, PSL Research University, Sorbonne University, INSERM U830, DNA repair and uveal melanoma, Equipe labellisée par la Ligue Nationale contre le Cancer, Paris, France
| | - Nathalie Droin
- Institut Gustave Roussy, INSERM 1287, Université Paris Saclay, Villejuif, France
| | - Benoit Palancade
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Benoit Miotto
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France
| | - Frédéric Chédin
- Department of Molecular and Cellular Biology and Genome Center, University of California, Davis, CA, USA
| | - Michaela Fontenay
- Université Paris Cité, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Cochin, Paris, France.
- Equipe labellisée par la Fondation pour la Recherche Médicale, Paris, France.
- Laboratoire d'excellence du Globule Rouge GR-Ex, Université Paris Cité, Paris, France.
- Assistance Publique-Hôpitaux de Paris.Centre-Université Paris Cité, Hôpital Cochin, Laboratory of Hematology, Paris, France.
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10
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Mukhopadhyay P, Miller H, Stoja A, Bishop AJR. Approaches for Mapping and Analysis of R-loops. Curr Protoc 2024; 4:e1037. [PMID: 38666626 DOI: 10.1002/cpz1.1037] [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] [Indexed: 05/04/2024]
Abstract
R-loops are nucleic acid structures composed of a DNA:RNA hybrid with a displaced non-template single-stranded DNA. Current approaches to identify and map R-loop formation across the genome employ either an antibody targeted against R-loops (S9.6) or a catalytically inactivated form of RNase H1 (dRNH1), a nuclease that can bind and resolve DNA:RNA hybrids via RNA exonuclease activity. This overview article outlines several ways to map R-loops using either methodology, explaining the differences and similarities among the approaches. Bioinformatic analysis of R-loops involves several layers of quality control and processing before visualizing the data. This article provides resources and tools that can be used to accurately process R-loop mapping data and explains the advantages and disadvantages of the resources as compared to one another. © 2024 Wiley Periodicals LLC.
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Affiliation(s)
- Pramiti Mukhopadhyay
- Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, Texas
| | | | - Aiola Stoja
- Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, Texas
| | - Alexander J R Bishop
- Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, Texas
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11
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Rivosecchi J, Jurikova K, Cusanelli E. Telomere-specific regulation of TERRA and its impact on telomere stability. Semin Cell Dev Biol 2024; 157:3-23. [PMID: 38088000 DOI: 10.1016/j.semcdb.2023.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/02/2023] [Indexed: 01/08/2024]
Abstract
TERRA is a class of telomeric repeat-containing RNAs that are expressed from telomeres in multiple organisms. TERRA transcripts play key roles in telomere maintenance and their physiological levels are essential to maintain the integrity of telomeric DNA. Indeed, deregulated TERRA expression or its altered localization can impact telomere stability by multiple mechanisms including fueling transcription-replication conflicts, promoting resection of chromosome ends, altering the telomeric chromatin, and supporting homologous recombination. Therefore, a fine-tuned control of TERRA is important to maintain the integrity of the genome. Several studies have reported that different cell lines express substantially different levels of TERRA. Most importantly, TERRA levels markedly vary among telomeres of a given cell type, indicating the existence of telomere-specific regulatory mechanisms which may help coordinate TERRA functions. TERRA molecules contain distinct subtelomeric sequences, depending on their telomere of origin, which may instruct specific post-transcriptional modifications or mediate distinct functions. In addition, all TERRA transcripts share a repetitive G-rich sequence at their 3' end which can form DNA:RNA hybrids and fold into G-quadruplex structures. Both structures are involved in TERRA functions and can critically affect telomere stability. In this review, we examine the mechanisms controlling TERRA levels and the impact of their telomere-specific regulation on telomere stability. We compare evidence obtained in different model organisms, discussing recent advances as well as controversies in the field. Furthermore, we discuss the importance of DNA:RNA hybrids and G-quadruplex structures in the context of TERRA biology and telomere maintenance.
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Affiliation(s)
- Julieta Rivosecchi
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy
| | - Katarina Jurikova
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy; Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina, 84215 Bratislava, Slovakia
| | - Emilio Cusanelli
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy.
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12
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Woolley PR, Wen X, Conway OM, Ender NA, Lee JH, Paull TT. Regulation of transcription patterns, poly(ADP-ribose), and RNA-DNA hybrids by the ATM protein kinase. Cell Rep 2024; 43:113896. [PMID: 38442018 PMCID: PMC11022685 DOI: 10.1016/j.celrep.2024.113896] [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: 06/01/2023] [Revised: 01/11/2024] [Accepted: 02/15/2024] [Indexed: 03/07/2024] Open
Abstract
The ataxia telangiectasia mutated (ATM) protein kinase is a master regulator of the DNA damage response and also an important sensor of oxidative stress. Analysis of gene expression in ataxia-telangiectasia (A-T) patient brain tissue shows that large-scale transcriptional changes occur in patient cerebellum that correlate with the expression level and guanine-cytosine (GC) content of transcribed genes. In human neuron-like cells in culture, we map locations of poly(ADP-ribose) and RNA-DNA hybrid accumulation genome-wide with ATM inhibition and find that these marks also coincide with high transcription levels, active transcription histone marks, and high GC content. Antioxidant treatment reverses the accumulation of R-loops in transcribed regions, consistent with the central role of reactive oxygen species in promoting these lesions. Based on these results, we postulate that transcription-associated lesions accumulate in ATM-deficient cells and that the single-strand breaks and PARylation at these sites ultimately generate changes in transcription that compromise cerebellum function and lead to neurodegeneration over time in A-T patients.
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Affiliation(s)
- Phillip R Woolley
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Xuemei Wen
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Olivia M Conway
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Nicolette A Ender
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Ji-Hoon Lee
- Department of Biological Sciences, Research Center of Ecomimetics, Chonnam National University, Gwangju 61186, Republic of Korea.
| | - Tanya T Paull
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA.
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13
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Westover KR, Jin P, Yao B. Bridging the gap: R-loop mediated genomic instability and its implications in neurological diseases. Epigenomics 2024; 16:589-608. [PMID: 38530068 PMCID: PMC11160457 DOI: 10.2217/epi-2023-0379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 03/12/2024] [Indexed: 03/27/2024] Open
Abstract
R-loops, intricate three-stranded structures formed by RNA-DNA hybrids and an exposed non-template DNA strand, are fundamental to various biological phenomena. They carry out essential and contrasting functions within cellular mechanisms, underlining their critical role in maintaining cellular homeostasis. The specific cellular context that dictates R-loop formation determines their function, particularly emphasizing the necessity for their meticulous genomic regulation. Notably, the aberrant formation or misregulation of R-loops is implicated in numerous neurological disorders. This review focuses on the complex interactions between R-loops and double-strand DNA breaks, exploring how R-loop dysregulation potentially contributes to the pathogenesis of various brain disorders, which could provide novel insights into the molecular mechanisms underpinning neurological disease progression and identify potential therapeutic targets by highlighting these aspects.
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Affiliation(s)
- Katherine R Westover
- Department of Human Genetics, Emory University, School of Medicine, Atlanta, GA 30322, USA
| | - Peng Jin
- Department of Human Genetics, Emory University, School of Medicine, Atlanta, GA 30322, USA
| | - Bing Yao
- Department of Human Genetics, Emory University, School of Medicine, Atlanta, GA 30322, USA
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14
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Huang TT, Chiang CY, Nair JR, Wilson KM, Cheng K, Lee JM. AKT1 interacts with DHX9 to Mitigate R Loop-Induced Replication Stress in Ovarian Cancer. Cancer Res 2024; 84:887-904. [PMID: 38241710 PMCID: PMC10947874 DOI: 10.1158/0008-5472.can-23-1908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/04/2023] [Accepted: 01/16/2024] [Indexed: 01/21/2024]
Abstract
PARP inhibitor (PARPi)-resistant BRCA-mutant (BRCAm) high-grade serous ovarian cancer (HGSOC) represents a new clinical challenge with unmet therapeutic needs. Here, we performed a quantitative high-throughput drug combination screen that identified the combination of an ATR inhibitor (ATRi) and an AKT inhibitor (AKTi) as an effective treatment strategy for both PARPi-sensitive and PARPi-resistant BRCAm HGSOC. The ATRi and AKTi combination induced DNA damage and R loop-mediated replication stress (RS). Mechanistically, the kinase domain of AKT1 directly interacted with DHX9 and facilitated recruitment of DHX9 to R loops. AKTi increased ATRi-induced R loop-mediated RS by mitigating recruitment of DHX9 to R loops. Moreover, DHX9 was upregulated in tumors from patients with PARPi-resistant BRCAm HGSOC, and high coexpression of DHX9 and AKT1 correlated with worse survival. Together, this study reveals an interaction between AKT1 and DHX9 that facilitates R loop resolution and identifies combining ATRi and AKTi as a rational treatment strategy for BRCAm HGSOC irrespective of PARPi resistance status. SIGNIFICANCE Inhibition of the AKT and ATR pathways cooperatively induces R loop-associated replication stress in high-grade serous ovarian cancer, providing rationale to support the clinical development of AKT and ATR inhibitor combinations. See related commentary by Ramanarayanan and Oberdoerffer, p. 793.
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Affiliation(s)
- Tzu-Ting Huang
- Women’s Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Chih-Yuan Chiang
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Jayakumar R. Nair
- Women’s Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Kelli M. Wilson
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Ken Cheng
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Jung-Min Lee
- Women’s Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
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15
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Parsons AM, Su K, Daniels M, Bouma GJ, Vanden Heuvel GB, Larson ED. Human PKD1 sequences form R-loop structures in vitro. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001058. [PMID: 38371318 PMCID: PMC10873753 DOI: 10.17912/micropub.biology.001058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/08/2024] [Accepted: 01/30/2024] [Indexed: 02/20/2024]
Abstract
Autosomal dominant polycystic kidney disease results from the loss of the PKD1 gene product, polycystin 1. Regulatory mechanisms are unresolved, but an apparent G/C sequence bias in the gene is consistent with co-transcriptional R-loop formation. R-loops regulate gene expression and stability, and they form when newly synthesized RNA extensively pairs with the template DNA to displace the non-template strand. In this study, we tested two human PKD1 sequences for co-transcriptional R-loop formation in vitro. We observed RNase H-sensitive R-loop formation in intron 1 and 22 sequences, but only in one transcriptional orientation. Therefore, R-loops may participate in PKD1 expression or stability.
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Affiliation(s)
- Agata M Parsons
- Biomedical Sciences, Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, United States
| | - Kemin Su
- Investigative Medicine, Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, United States
| | - Maya Daniels
- Biomedical Sciences, Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, United States
| | - Gerrit J Bouma
- Biomedical Sciences, Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, United States
| | - Gregory B Vanden Heuvel
- Biomedical Sciences, Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, United States
| | - Erik D Larson
- Biomedical Sciences, Western Michigan University Homer Stryker MD School of Medicine, Kalamazoo, Michigan, United States
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16
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Lee JD, Bae W. Unscheduled excessive R-loops in immune response. Funct Integr Genomics 2024; 24:7. [PMID: 38189844 DOI: 10.1007/s10142-024-01288-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/29/2023] [Accepted: 01/02/2024] [Indexed: 01/09/2024]
Affiliation(s)
- Jiah D Lee
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Woori Bae
- Department of Biochemistry & Molecular Pharmacology, New York University School of Medicine, New York, NY, USA.
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17
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Kumar C, Remus D. Looping out of control: R-loops in transcription-replication conflict. Chromosoma 2024; 133:37-56. [PMID: 37419963 PMCID: PMC10771546 DOI: 10.1007/s00412-023-00804-8] [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: 04/18/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/09/2023]
Abstract
Transcription-replication conflict is a major cause of replication stress that arises when replication forks collide with the transcription machinery. Replication fork stalling at sites of transcription compromises chromosome replication fidelity and can induce DNA damage with potentially deleterious consequences for genome stability and organismal health. The block to DNA replication by the transcription machinery is complex and can involve stalled or elongating RNA polymerases, promoter-bound transcription factor complexes, or DNA topology constraints. In addition, studies over the past two decades have identified co-transcriptional R-loops as a major source for impairment of DNA replication forks at active genes. However, how R-loops impede DNA replication at the molecular level is incompletely understood. Current evidence suggests that RNA:DNA hybrids, DNA secondary structures, stalled RNA polymerases, and condensed chromatin states associated with R-loops contribute to the of fork progression. Moreover, since both R-loops and replication forks are intrinsically asymmetric structures, the outcome of R-loop-replisome collisions is influenced by collision orientation. Collectively, the data suggest that the impact of R-loops on DNA replication is highly dependent on their specific structural composition. Here, we will summarize our current understanding of the molecular basis for R-loop-induced replication fork progression defects.
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Affiliation(s)
- Charanya Kumar
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, USA
| | - Dirk Remus
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, USA.
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18
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Jaiswal AS, Dutta A, Srinivasan G, Yuan Y, Zhou D, Shaheen M, Sadideen D, Kirby A, Williamson E, Gupta Y, Olsen SK, Xu M, Loranc E, Mukhopadhyay P, Pertsemlidis A, Bishop AR, Sung P, Nickoloff J, Hromas R. TATDN2 resolution of R-loops is required for survival of BRCA1-mutant cancer cells. Nucleic Acids Res 2023; 51:12224-12241. [PMID: 37953292 PMCID: PMC10711561 DOI: 10.1093/nar/gkad952] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 10/03/2023] [Accepted: 10/18/2023] [Indexed: 11/14/2023] Open
Abstract
BRCA1-deficient cells have increased IRE1 RNase, which degrades multiple microRNAs. Reconstituting expression of one of these, miR-4638-5p, resulted in synthetic lethality in BRCA1-deficient cancer cells. We found that miR-4638-5p represses expression of TATDN2, a poorly characterized member of the TATD nuclease family. We discovered that human TATDN2 has RNA 3' exonuclease and endonuclease activity on double-stranded hairpin RNA structures. Given the cleavage of hairpin RNA by TATDN2, and that BRCA1-deficient cells have difficulty resolving R-loops, we tested whether TATDN2 could resolve R-loops. Using in vitro biochemical reconstitution assays, we found TATDN2 bound to R-loops and degraded the RNA strand but not DNA of multiple forms of R-loops in vitro in a Mg2+-dependent manner. Mutations in amino acids E593 and E705 predicted by Alphafold-2 to chelate an essential Mg2+ cation completely abrogated this R-loop resolution activity. Depleting TATDN2 increased cellular R-loops, DNA damage and chromosomal instability. Loss of TATDN2 resulted in poor replication fork progression in the presence of increased R-loops. Significantly, we found that TATDN2 is essential for survival of BRCA1-deficient cancer cells, but much less so for cognate BRCA1-repleted cancer cells. Thus, we propose that TATDN2 is a novel target for therapy of BRCA1-deficient cancers.
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Affiliation(s)
- Aruna S Jaiswal
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Arijit Dutta
- Department of Biochemistry and Structural Biology and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Gayathri Srinivasan
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Yaxia Yuan
- Department of Biochemistry and Structural Biology and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Daohong Zhou
- Department of Biochemistry and Structural Biology and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Montaser Shaheen
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Doraid T Sadideen
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Austin Kirby
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Elizabeth A Williamson
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Yogesh K Gupta
- Department of Biochemistry and Structural Biology and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Shaun K Olsen
- Department of Biochemistry and Structural Biology and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Mingjiang Xu
- Department of Molecular Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Eva Loranc
- Department of Cell Systems and Anatomy and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Pramiti Mukhopadhyay
- Department of Cell Systems and Anatomy and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Alexander Pertsemlidis
- Department of Cell Systems and Anatomy and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Alexander J R Bishop
- Department of Cell Systems and Anatomy and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Patrick Sung
- Department of Biochemistry and Structural Biology and the Greehey Children's Cancer Research Institute, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
| | - Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Robert Hromas
- Department of Medicine and the Mays Cancer Center, the University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA
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19
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Woolley PR, Wen X, Conway OM, Ender NA, Lee JH, Paull TT. Regulation of transcription patterns, poly-ADP-ribose, and RNA-DNA hybrids by the ATM protein kinase. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.06.570417. [PMID: 38106035 PMCID: PMC10723464 DOI: 10.1101/2023.12.06.570417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
The ATM protein kinase is a master regulator of the DNA damage response and also an important sensor of oxidative stress. Analysis of gene expression in Ataxia-telangiectasia patient brain tissue shows that large-scale transcriptional changes occur in patient cerebellum that correlate with expression level and GC content of transcribed genes. In human neuron-like cells in culture we map locations of poly-ADP-ribose and RNA-DNA hybrid accumulation genome-wide with ATM inhibition and find that these marks also coincide with high transcription levels, active transcription histone marks, and high GC content. Antioxidant treatment reverses the accumulation of R-loops in transcribed regions, consistent with the central role of ROS in promoting these lesions. Based on these results we postulate that transcription-associated lesions accumulate in ATM-deficient cells and that the single-strand breaks and PARylation at these sites ultimately generate changes in transcription that compromise cerebellum function and lead to neurodegeneration over time in A-T patients.
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Affiliation(s)
- Phillip R. Woolley
- The University of Texas at Austin, Department of Molecular Biosciences, Austin, TX, 78712
| | - Xuemei Wen
- The University of Texas at Austin, Department of Molecular Biosciences, Austin, TX, 78712
| | - Olivia M. Conway
- The University of Texas at Austin, Department of Molecular Biosciences, Austin, TX, 78712
| | - Nicolette A. Ender
- The University of Texas at Austin, Department of Molecular Biosciences, Austin, TX, 78712
| | - Ji-Hoon Lee
- Department of Biological Sciences, Research Center of Ecomimetics, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Tanya T. Paull
- The University of Texas at Austin, Department of Molecular Biosciences, Austin, TX, 78712
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20
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Kumari N, Das K, Sharma S, Dahal S, Desai SS, Roy U, Sharma A, Manjunath M, Gopalakrishnan V, Retheesh ST, Javadekar SM, Choudhary B, Raghavan SC. Evaluation of potential role of R-loop and G-quadruplex DNA in the fragility of c-MYC during chromosomal translocation associated with Burkitt's lymphoma. J Biol Chem 2023; 299:105431. [PMID: 37926284 PMCID: PMC10704377 DOI: 10.1016/j.jbc.2023.105431] [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: 08/15/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/07/2023] Open
Abstract
t(8;14) translocation is the hallmark of Burkitt's lymphoma and results in c-MYC deregulation. During the translocation, c-MYC gene on chromosome 8 gets juxtaposed to the Ig switch regions on chromosome 14. Although the promoter of c-MYC has been investigated for its mechanism of fragility, little is known about other c-MYC breakpoint regions. We have analyzed the translocation break points at the exon 1/intron 1 of c-MYC locus from patients with Burkitt's lymphoma. Results showed that the breakpoint region, when present on a plasmid, could fold into an R-loop confirmation in a transcription-dependent manner. Sodium bisulfite modification assay revealed significant single-strandedness on chromosomal DNA of Burkitt's lymphoma cell line, Raji, and normal lymphocytes, revealing distinct R-loops covering up to 100 bp region. Besides, ChIP-DRIP analysis reveals that the R-loop antibody can bind to the breakpoint region. Further, we show the formation of stable parallel intramolecular G-quadruplex on non-template strand of the genome. Finally, incubation of purified AID in vitro or overexpression of AID within the cells led to enhanced mutation frequency at the c-MYC breakpoint region. Interestingly, anti-γH2AX can bind to DSBs generated at the c-MYC breakpoint region within the cells. The formation of R-loop and G-quadruplex was found to be mutually exclusive. Therefore, our results suggest that AID can bind to the single-stranded region of the R-loop and G4 DNA, leading to the deamination of cytosines to uracil and induction of DNA breaks in one of the DNA strands, leading to double-strand break, which could culminate in t(8;14) chromosomal translocation.
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Affiliation(s)
- Nitu Kumari
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Kohal Das
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Shivangi Sharma
- Department of Biochemistry, Indian Institute of Science, Bangalore, India; Institute of Bioinformatics and Applied Biotechnology, Bangalore, India
| | - Sumedha Dahal
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Urbi Roy
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Anju Sharma
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Meghana Manjunath
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, India
| | - Vidya Gopalakrishnan
- Department of Biochemistry, Indian Institute of Science, Bangalore, India; Department of Zoology, St Joseph's College, Irinjalakuda, Kerala, India
| | - S T Retheesh
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Saniya M Javadekar
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Bibha Choudhary
- Institute of Bioinformatics and Applied Biotechnology, Bangalore, India
| | - Sathees C Raghavan
- Department of Biochemistry, Indian Institute of Science, Bangalore, India.
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21
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Wu Y, Song T, Xu Q. R-LOOPs on Short Tandem Repeat Expansion Disorders in Neurodegenerative Diseases. Mol Neurobiol 2023; 60:7185-7195. [PMID: 37540313 DOI: 10.1007/s12035-023-03531-4] [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: 05/16/2023] [Accepted: 07/24/2023] [Indexed: 08/05/2023]
Abstract
Expansions of short tandem repeats (STRs) have been found to be present in more than 50 diseases and have a close connection with neurodegenerative diseases. Transcriptional silencing and R-LOOP formation, RNA-mediated sequestration of RNA-binding proteins (RBPs), gain-of-function (GOF) proteins containing expanded repeats, and repeat-associated non-AUG (RAN) translation of toxic repeat peptides are some potential molecular mechanisms underlying STR expansion disorders. R-LOOP, a byproduct of transcription, is a three-stranded nucleic acid structure with abnormal accumulation that participates in the pathogenesis of STR expansion disorders by inducing DNA damage and genome instability. R-LOOPs can engender a series of DNA damage, such as DNA double-strand breaks (DSBs), single-strand breaks (SSBs), DNA recombination, or mutations in the DNA replication, transcription, or repair processes. In this review, we provide an in-depth discussion of recent advancements in R-LOOP and systematically elaborate on its genetic destabilizing effects in several neurodegenerative diseases. These molecular mechanisms will provide novel targets for drug design and therapeutic upgrading of these devastating diseases.
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Affiliation(s)
- Yiting Wu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Tingwei Song
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Qian Xu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, China.
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China.
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22
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Nickoloff JA, Jaiswal AS, Sharma N, Williamson EA, Tran MT, Arris D, Yang M, Hromas R. Cellular Responses to Widespread DNA Replication Stress. Int J Mol Sci 2023; 24:16903. [PMID: 38069223 PMCID: PMC10707325 DOI: 10.3390/ijms242316903] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Replicative DNA polymerases are blocked by nearly all types of DNA damage. The resulting DNA replication stress threatens genome stability. DNA replication stress is also caused by depletion of nucleotide pools, DNA polymerase inhibitors, and DNA sequences or structures that are difficult to replicate. Replication stress triggers complex cellular responses that include cell cycle arrest, replication fork collapse to one-ended DNA double-strand breaks, induction of DNA repair, and programmed cell death after excessive damage. Replication stress caused by specific structures (e.g., G-rich sequences that form G-quadruplexes) is localized but occurs during the S phase of every cell division. This review focuses on cellular responses to widespread stress such as that caused by random DNA damage, DNA polymerase inhibition/nucleotide pool depletion, and R-loops. Another form of global replication stress is seen in cancer cells and is termed oncogenic stress, reflecting dysregulated replication origin firing and/or replication fork progression. Replication stress responses are often dysregulated in cancer cells, and this too contributes to ongoing genome instability that can drive cancer progression. Nucleases play critical roles in replication stress responses, including MUS81, EEPD1, Metnase, CtIP, MRE11, EXO1, DNA2-BLM, SLX1-SLX4, XPF-ERCC1-SLX4, Artemis, XPG, FEN1, and TATDN2. Several of these nucleases cleave branched DNA structures at stressed replication forks to promote repair and restart of these forks. We recently defined roles for EEPD1 in restarting stressed replication forks after oxidative DNA damage, and for TATDN2 in mitigating replication stress caused by R-loop accumulation in BRCA1-defective cells. We also discuss how insights into biological responses to genome-wide replication stress can inform novel cancer treatment strategies that exploit synthetic lethal relationships among replication stress response factors.
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Affiliation(s)
- Jac A. Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Aruna S. Jaiswal
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Elizabeth A. Williamson
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Manh T. Tran
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Dominic Arris
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Ming Yang
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Robert Hromas
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
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23
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Gambelli A, Ferrando A, Boncristiani C, Schoeftner S. Regulation and function of R-loops at repetitive elements. Biochimie 2023; 214:141-155. [PMID: 37619810 DOI: 10.1016/j.biochi.2023.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/13/2023] [Accepted: 08/19/2023] [Indexed: 08/26/2023]
Abstract
R-loops are atypical, three-stranded nucleic acid structures that contain a stretch of RNA:DNA hybrids and an unpaired, single stranded DNA loop. R-loops are physiological relevant and can act as regulators of gene expression, chromatin structure, DNA damage repair and DNA replication. However, unscheduled and persistent R-loops are mutagenic and can mediate replication-transcription conflicts, leading to DNA damage and genome instability if left unchecked. Detailed transcriptome analysis unveiled that 85% of the human genome, including repetitive regions, hold transcriptional activity. This anticipates that R-loops management plays a central role for the regulation and integrity of genomes. This function is expected to have a particular relevance for repetitive sequences that make up to 75% of the human genome. Here, we review the impact of R-loops on the function and stability of repetitive regions such as centromeres, telomeres, rDNA arrays, transposable elements and triplet repeat expansions and discuss their relevance for associated pathological conditions.
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Affiliation(s)
- Alice Gambelli
- Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Via E. Weiss 2, 34127, Trieste, Italy
| | - Alessandro Ferrando
- Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Via E. Weiss 2, 34127, Trieste, Italy
| | - Chiara Boncristiani
- Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Via E. Weiss 2, 34127, Trieste, Italy
| | - Stefan Schoeftner
- Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Via E. Weiss 2, 34127, Trieste, Italy.
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24
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Camino LP, Dutta A, Barroso S, Pérez-Calero C, Katz JN, García-Rubio M, Sung P, Gómez-González B, Aguilera A. DICER ribonuclease removes harmful R-loops. Mol Cell 2023; 83:3707-3719.e5. [PMID: 37827159 PMCID: PMC11034902 DOI: 10.1016/j.molcel.2023.09.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 07/08/2023] [Accepted: 09/19/2023] [Indexed: 10/14/2023]
Abstract
R-loops, which consist of a DNA-RNA hybrid and a displaced DNA strand, are known to threaten genome integrity. To counteract this, different mechanisms suppress R-loop accumulation by either preventing the hybridization of RNA with the DNA template (RNA biogenesis factors), unwinding the hybrid (DNA-RNA helicases), or degrading the RNA moiety of the R-loop (type H ribonucleases [RNases H]). Thus far, RNases H are the only nucleases known to cleave DNA-RNA hybrids. Now, we show that the RNase DICER also resolves R-loops. Biochemical analysis reveals that DICER acts by specifically cleaving the RNA within R-loops. Importantly, a DICER RNase mutant impaired in R-loop processing causes a strong accumulation of R-loops in cells. Our results thus not only reveal a function of DICER as an R-loop resolvase independent of DROSHA but also provide evidence for the role of multi-functional RNA processing factors in the maintenance of genome integrity in higher eukaryotes.
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Affiliation(s)
- Lola P Camino
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla, CSIC, 41092 Seville, Spain; Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Arijit Dutta
- Greehey Children's Cancer Research Institute, Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Sonia Barroso
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla, CSIC, 41092 Seville, Spain; Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Carmen Pérez-Calero
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla, CSIC, 41092 Seville, Spain; Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Jeffrey N Katz
- Greehey Children's Cancer Research Institute, Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - María García-Rubio
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla, CSIC, 41092 Seville, Spain; Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Patrick Sung
- Greehey Children's Cancer Research Institute, Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
| | - Belén Gómez-González
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla, CSIC, 41092 Seville, Spain; Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain.
| | - Andrés Aguilera
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla, CSIC, 41092 Seville, Spain; Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain.
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25
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Li F, Zafar A, Luo L, Denning AM, Gu J, Bennett A, Yuan F, Zhang Y. R-Loops in Genome Instability and Cancer. Cancers (Basel) 2023; 15:4986. [PMID: 37894353 PMCID: PMC10605827 DOI: 10.3390/cancers15204986] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/04/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023] Open
Abstract
R-loops are unique, three-stranded nucleic acid structures that primarily form when an RNA molecule displaces one DNA strand and anneals to the complementary DNA strand in a double-stranded DNA molecule. R-loop formation can occur during natural processes, such as transcription, in which the nascent RNA molecule remains hybridized with the template DNA strand, while the non-template DNA strand is displaced. However, R-loops can also arise due to many non-natural processes, including DNA damage, dysregulation of RNA degradation pathways, and defects in RNA processing. Despite their prevalence throughout the whole genome, R-loops are predominantly found in actively transcribed gene regions, enabling R-loops to serve seemingly controversial roles. On one hand, the pathological accumulation of R-loops contributes to genome instability, a hallmark of cancer development that plays a role in tumorigenesis, cancer progression, and therapeutic resistance. On the other hand, R-loops play critical roles in regulating essential processes, such as gene expression, chromatin organization, class-switch recombination, mitochondrial DNA replication, and DNA repair. In this review, we summarize discoveries related to the formation, suppression, and removal of R-loops and their influence on genome instability, DNA repair, and oncogenic events. We have also discussed therapeutical opportunities by targeting pathological R-loops.
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Affiliation(s)
- Fang Li
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Alyan Zafar
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Liang Luo
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Ariana Maria Denning
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Jun Gu
- Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Ansley Bennett
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Fenghua Yuan
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Yanbin Zhang
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
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26
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Yang H, Lachtara EM, Ran X, Hopkins J, Patel PS, Zhu X, Xiao Y, Phoon L, Gao B, Zou L, Lawrence MS, Lan L. The RNA m5C modification in R-loops as an off switch of Alt-NHEJ. Nat Commun 2023; 14:6114. [PMID: 37777505 PMCID: PMC10542358 DOI: 10.1038/s41467-023-41790-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 09/19/2023] [Indexed: 10/02/2023] Open
Abstract
The roles of R-loops and RNA modifications in homologous recombination (HR) and other DNA double-stranded break (DSB) repair pathways remain poorly understood. Here, we find that DNA damage-induced RNA methyl-5-cytosine (m5C) modification in R-loops plays a crucial role to regulate PARP1-mediated poly ADP-ribosylation (PARylation) and the choice of DSB repair pathways at sites of R-loops. Through bisulfite sequencing, we discover that the methyltransferase TRDMT1 preferentially generates m5C after DNA damage in R-loops across the genome. In the absence of m5C, R-loops activate PARP1-mediated PARylation both in vitro and in cells. Concurrently, m5C promotes transcription-coupled HR (TC-HR) while suppressing PARP1-dependent alternative non-homologous end joining (Alt-NHEJ), favoring TC-HR over Alt-NHEJ in transcribed regions as the preferred repair pathway. Importantly, simultaneous disruption of both TC-HR and Alt-NHEJ with TRDMT1 and PARP or Polymerase θ inhibitors prevents alternative DSB repair and exhibits synergistic cytotoxic effects on cancer cells, suggesting an effective strategy to exploit genomic instability in cancer therapy.
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Affiliation(s)
- Haibo Yang
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Emily M Lachtara
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Xiaojuan Ran
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, USA
| | - Jessica Hopkins
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Parasvi S Patel
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Xueping Zhu
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Yao Xiao
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Laiyee Phoon
- Departments of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, USA
| | - Boya Gao
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Lee Zou
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, USA
| | - Michael S Lawrence
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Li Lan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA.
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
- Departments of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, USA.
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27
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Savoca V, Rivosecchi J, Gaiatto A, Rossi A, Mosca R, Gialdini I, Zubovic L, Tebaldi T, Macchi P, Cusanelli E. TERRA stability is regulated by RALY and polyadenylation in a telomere-specific manner. Cell Rep 2023; 42:112406. [PMID: 37060569 DOI: 10.1016/j.celrep.2023.112406] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/25/2023] [Accepted: 03/31/2023] [Indexed: 04/16/2023] Open
Abstract
Telomeric repeat-containing RNA (TERRA) is a long non-coding RNA transcribed from telomeres that plays key roles in telomere maintenance. A fraction of TERRA is polyadenylated, and the presence of the poly(A) tail influences TERRA localization and stability. However, the mechanisms of TERRA biogenesis remain mostly elusive. Here, we show that the stability of TERRA transcripts is regulated by the RNA-binding protein associated with lethal yellow mutation (RALY). RALY depletion results in lower TERRA levels, impaired localization of TERRA at telomeres, and ultimately telomere damage. Importantly, we show that TERRA polyadenylation is telomere specific and that RALY preferentially stabilizes non-polyadenylated TERRA transcripts. Finally, we report that TERRA interacts with the poly(A)-binding protein nuclear 1 (PABPN1). Altogether, our results indicate that TERRA stability is regulated by the interplay between RALY and PABPN1, defined by the TERRA polyadenylation state. Our findings also suggest that different telomeres may trigger distinct TERRA-mediated responses.
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Affiliation(s)
- Valeria Savoca
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Julieta Rivosecchi
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Alice Gaiatto
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Annalisa Rossi
- Laboratory of Molecular and Cellular Neurobiology, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Riccardo Mosca
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Irene Gialdini
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Lorena Zubovic
- Laboratory of Molecular and Cellular Neurobiology, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Toma Tebaldi
- Laboratory of RNA and Disease Data Science, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy; Section of Hematology, Department of Internal Medicine, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA
| | - Paolo Macchi
- Laboratory of Molecular and Cellular Neurobiology, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy.
| | - Emilio Cusanelli
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy.
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28
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Elsakrmy N, Cui H. R-Loops and R-Loop-Binding Proteins in Cancer Progression and Drug Resistance. Int J Mol Sci 2023; 24:ijms24087064. [PMID: 37108225 PMCID: PMC10138518 DOI: 10.3390/ijms24087064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/06/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
R-loops are three-stranded DNA/RNA hybrids that form by the annealing of the mRNA transcript to its coding template while displacing the non-coding strand. While R-loop formation regulates physiological genomic and mitochondrial transcription and DNA damage response, imbalanced R-loop formation can be a threat to the genomic integrity of the cell. As such, R-loop formation is a double-edged sword in cancer progression, and perturbed R-loop homeostasis is observed across various malignancies. Here, we discuss the interplay between R-loops and tumor suppressors and oncogenes, with a focus on BRCA1/2 and ATR. R-loop imbalances contribute to cancer propagation and the development of chemotherapy drug resistance. We explore how R-loop formation can cause cancer cell death in response to chemotherapeutics and be used to circumvent drug resistance. As R-loop formation is tightly linked to mRNA transcription, their formation is unavoidable in cancer cells and can thus be explored in novel cancer therapeutics.
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Affiliation(s)
- Noha Elsakrmy
- Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
| | - Haissi Cui
- Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
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29
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Gong Y, Liu Y. R-Loops at Chromosome Ends: From Formation, Regulation, and Cellular Consequence. Cancers (Basel) 2023; 15:cancers15072178. [PMID: 37046839 PMCID: PMC10093737 DOI: 10.3390/cancers15072178] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 04/14/2023] Open
Abstract
Telomeric repeat containing RNA (TERRA) is transcribed from subtelomeric regions to telomeres. TERRA RNA can invade telomeric dsDNA and form telomeric R-loop structures. A growing body of evidence suggests that TERRA-mediated R-loops are critical players in telomere length homeostasis. Here, we will review current knowledge on the regulation of R-loop levels at telomeres. In particular, we will discuss how the central player TERRA and its binding proteins modulate R-loop levels through various mechanisms. We will further provide an overview of the consequences of TERRA-mediated persistent or unscheduled R-loops at telomeres in human ALT cancers and other organisms, with a focus on telomere length regulation after replication interference-induced damage and DNA homologous recombination-mediated repair.
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Affiliation(s)
- Yi Gong
- Laboratory of Genetics and Genomics, National Institute on Aging/National Institutes of Health, 251 Bayview Blvd, Baltimore, MD 21224, USA
| | - Yie Liu
- Laboratory of Genetics and Genomics, National Institute on Aging/National Institutes of Health, 251 Bayview Blvd, Baltimore, MD 21224, USA
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30
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Laspata N, Kaur P, Mersaoui S, Muoio D, Liu Z, Bannister MH, Nguyen H, Curry C, Pascal J, Poirier G, Wang H, Masson JY, Fouquerel E. PARP1 associates with R-loops to promote their resolution and genome stability. Nucleic Acids Res 2023; 51:2215-2237. [PMID: 36794853 PMCID: PMC10018367 DOI: 10.1093/nar/gkad066] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 01/19/2023] [Accepted: 02/09/2023] [Indexed: 02/17/2023] Open
Abstract
PARP1 is a DNA-dependent ADP-Ribose transferase with ADP-ribosylation activity that is triggered by DNA breaks and non-B DNA structures to mediate their resolution. PARP1 was also recently identified as a component of the R-loop-associated protein-protein interaction network, suggesting a potential role for PARP1 in resolving this structure. R-loops are three-stranded nucleic acid structures that consist of a RNA-DNA hybrid and a displaced non-template DNA strand. R-loops are involved in crucial physiological processes but can also be a source of genome instability if persistently unresolved. In this study, we demonstrate that PARP1 binds R-loops in vitro and associates with R-loop formation sites in cells which activates its ADP-ribosylation activity. Conversely, PARP1 inhibition or genetic depletion causes an accumulation of unresolved R-loops which promotes genomic instability. Our study reveals that PARP1 is a novel sensor for R-loops and highlights that PARP1 is a suppressor of R-loop-associated genomic instability.
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Affiliation(s)
- Natalie Laspata
- UPMC Hillman Cancer Center, University of Pittsburgh Cancer Institute, Department of Pharmacology and Chemical Biology, Pittsburgh, PA 15213, USA
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Parminder Kaur
- Physics Department, Raleigh, NC 27695, USA
- Center for Human Health and the Environment, Raleigh, NC 27695, USA
| | - Sofiane Yacine Mersaoui
- CHU de Québec Research Centre, HDQ Pavilion, Oncology Division, Laval University Cancer Research Center, McMahon, Québec City, Québec G1R 3S3, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec, Canada
| | - Daniela Muoio
- UPMC Hillman Cancer Center, University of Pittsburgh Cancer Institute, Department of Pharmacology and Chemical Biology, Pittsburgh, PA 15213, USA
| | - Zhiyan Silvia Liu
- Department of Pharmacology, The Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Maxwell Henry Bannister
- Department of Pharmacology, The Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Hai Dang Nguyen
- Department of Pharmacology, The Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Caroline Curry
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - John M Pascal
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Guy G Poirier
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec, Canada
- CHU de Québec Research Centre, CHUL Pavilion, Oncology Division, Quebec, Canada
| | - Hong Wang
- Physics Department, Raleigh, NC 27695, USA
- Center for Human Health and the Environment, Raleigh, NC 27695, USA
- Toxicology Program, North Carolina State University, Raleigh, NC, USA
| | - Jean-Yves Masson
- CHU de Québec Research Centre, HDQ Pavilion, Oncology Division, Laval University Cancer Research Center, McMahon, Québec City, Québec G1R 3S3, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec, Canada
| | - Elise Fouquerel
- UPMC Hillman Cancer Center, University of Pittsburgh Cancer Institute, Department of Pharmacology and Chemical Biology, Pittsburgh, PA 15213, USA
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31
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Yeo SJ, Ying C, Fullwood MJ, Tergaonkar V. Emerging regulatory mechanisms of noncoding RNAs in topologically associating domains. Trends Genet 2023; 39:217-232. [PMID: 36642680 DOI: 10.1016/j.tig.2022.12.003] [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: 08/15/2022] [Revised: 12/17/2022] [Accepted: 12/20/2022] [Indexed: 01/15/2023]
Abstract
Topologically associating domains (TADs) are integral to spatial genome organization, instructing gene expression, and cell fate. Recently, several advances have uncovered roles for noncoding RNAs (ncRNAs) in the regulation of the form and function of mammalian TADs. Phase separation has also emerged as a potential arbiter of ncRNAs in the regulation of TADs. In this review we discuss the implications of these novel findings in relation to how ncRNAs might structurally and functionally regulate TADs from two perspectives: moderating loop extrusion through interactions with architectural proteins, and facilitating TAD phase separation. Additionally, we propose future studies and directions to investigate these phenomena.
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Affiliation(s)
- Samuel Jianjie Yeo
- Laboratory of NFκB Signaling, Institute of Molecular Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University (NTU), Singapore 308232, Singapore
| | - Chen Ying
- Laboratory of NFκB Signaling, Institute of Molecular Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore
| | - Melissa Jane Fullwood
- Cancer Science Institute of Singapore, Centre for Translational Medicine, National University of Singapore, Singapore 117599, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.
| | - Vinay Tergaonkar
- Laboratory of NFκB Signaling, Institute of Molecular Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore; Department of Pathology and the Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore.
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32
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Miller HE, Montemayor D, Li J, Levy SA, Pawar R, Hartono S, Sharma K, Frost B, Chedin F, Bishop AJR. Exploration and analysis of R-loop mapping data with RLBase. Nucleic Acids Res 2023; 51:D1129-D1137. [PMID: 36039757 PMCID: PMC9825527 DOI: 10.1093/nar/gkac732] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/17/2022] [Indexed: 01/30/2023] Open
Abstract
R-loops are three-stranded nucleic acid structures formed from the hybridization of RNA and DNA. In 2012, Ginno et al. introduced the first R-loop mapping method. Since that time, dozens of R-loop mapping studies have been conducted, yielding hundreds of publicly available datasets. Current R-loop databases provide only limited access to these data. Moreover, no web tools for analyzing user-supplied R-loop datasets have yet been described. In our recent work, we reprocessed 810 R-loop mapping samples, building the largest R-loop data resource to date. We also defined R-loop consensus regions and developed a framework for R-loop data analysis. Now, we introduce RLBase, a user-friendly database that provides the capability to (i) explore hundreds of public R-loop mapping datasets, (ii) explore R-loop consensus regions, (iii) analyze user-supplied data and (iv) download standardized and reprocessed datasets. RLBase is directly accessible via the following URL: https://gccri.bishop-lab.uthscsa.edu/shiny/rlbase/.
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Affiliation(s)
- Henry E Miller
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.,Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, TX 78229, USA.,Bioinformatics Research Network, Atlanta, GA 30317, USA
| | - Daniel Montemayor
- Department of Medicine, UT Health San Antonio, San Antonio, TX 78229, USA.,Center for Precision Medicine, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Janet Li
- Bioinformatics Research Network, Atlanta, GA 30317, USA.,Bioinformatics Graduate Program, University of British Columbia, Vancouver, BC V6T 1Z2, Canada.,Canada's Michael Smith Genome Sciences Center, BC Cancer Research, Vancouver, BC V5Z 1L3, Canada
| | - Simon A Levy
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.,Bioinformatics Research Network, Atlanta, GA 30317, USA.,Sam & Ann Barshop Institute for Longevity & Aging Studies, UT Health San Antonio, San Antonio, TX 78229, USA.,Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Roshan Pawar
- Bioinformatics Research Network, Atlanta, GA 30317, USA.,Faculty of Applied Science, University of British Columbia, Vancouver, BC V6T 1Z2, Canada
| | - Stella Hartono
- Department of Molecular and Cellular Biology, UC Davis, Davis, CA 95616, USA
| | - Kumar Sharma
- Department of Medicine, UT Health San Antonio, San Antonio, TX 78229, USA.,Center for Precision Medicine, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Bess Frost
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.,Sam & Ann Barshop Institute for Longevity & Aging Studies, UT Health San Antonio, San Antonio, TX 78229, USA.,Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Frédéric Chedin
- Department of Molecular and Cellular Biology, UC Davis, Davis, CA 95616, USA
| | - Alexander J R Bishop
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.,Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, TX 78229, USA.,May's Cancer Center, UT Health San Antonio, San Antonio, TX 78229, USA
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33
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Shen L, Yang Y. Detecting R-Loop Formation Using a Plasmid-Based In Vitro Transcription Assay. Methods Mol Biol 2023; 2666:265-278. [PMID: 37166671 DOI: 10.1007/978-1-0716-3191-1_19] [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: 05/12/2023]
Abstract
R-loops are three-stranded nucleic acid structures that consist of a DNA-RNA hybrid and a displaced single-stranded DNA. Since it was first reported by Ronald Davis and colleagues over 40 years ago, the study of R-loops has become an increasingly expanded area of research. Numerous factors have been identified to modulate the dynamic formation and resolution of R-loops, which are critical for proper controls of gene expression and genome stability. Along the lines of these discoveries, various biochemical and cellular assays have been developed to detect R-loop changes in vitro and in vivo. In this chapter, we describe a protocol for measuring R-loop formation using a plasmid-based in vitro transcription assay. The R-loop formed is then detected and quantified by using gel mobility, antibody staining, and DNA-RNA immunoprecipitation (DRIP)-qPCR assays. Unlike the helicase assay that uses short R-loop substrates, this assay system introduces DNA topology and active transcription as additional variables that impact R-loop formation, thus, more closely recapitulating in vivo situations. Furthermore, this method can be adopted for investigation of cis-elements and trans-acting factors that influence R-loop formation.
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Affiliation(s)
- Lei Shen
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope National Cancer Center, Duarte, CA, USA
| | - Yanzhong Yang
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope National Cancer Center, Duarte, CA, USA.
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34
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Gospodinov A, Dzhokova S, Petrova M, Ugrinova I. Chromatin regulators in DNA replication and genome stability maintenance during S-phase. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 135:243-280. [PMID: 37061334 DOI: 10.1016/bs.apcsb.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
The duplication of genetic information is central to life. The replication of genetic information is strictly controlled to ensure that each piece of genomic DNA is copied only once during a cell cycle. Factors that slow or stop replication forks cause replication stress. Replication stress is a major source of genome instability in cancer cells. Multiple control mechanisms facilitate the unimpeded fork progression, prevent fork collapse and coordinate fork repair. Chromatin alterations, caused by histone post-translational modifications and chromatin remodeling, have critical roles in normal replication and in avoiding replication stress and its consequences. This text reviews the chromatin regulators that ensure DNA replication and the proper response to replication stress. We also briefly touch on exploiting replication stress in therapeutic strategies. As chromatin regulators are frequently mutated in cancer, manipulating their activity could provide many possibilities for personalized treatment.
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Affiliation(s)
- Anastas Gospodinov
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
| | - Stefka Dzhokova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Maria Petrova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Iva Ugrinova
- Roumen Tsanev Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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35
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Sarker AH, Cooper PK. Slot Blot Assay for Detection of R Loops. Methods Mol Biol 2023; 2701:149-156. [PMID: 37574480 DOI: 10.1007/978-1-0716-3373-1_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
R loops (DNA-RNA hybrid) are three-stranded nucleic acid structures that comprise of template DNA strand hybridized with the nascent RNA leaving the displaced non-template strand. Although a programmed R loop formation can serve as powerful regulators of gene expression, these structures can also turn into major sources of genomic instability and contribute to the development of diseases. Therefore, understanding how cells prevent the deleterious consequences of R loops yet allow R loop formation to participate in various physiological processes will help to understand how their homeostasis is maintained. Detection and quantitative measurements of R loops are critical that largely relied on S9.6 antibody. Immunofluorescence methods are frequently used to localize and quantify R loops in the cell but they require specialized tools for analysis and relatively expensive; therefore, they are not always useful for initial assessments of R loop accumulation. Here, we describe an improved slot blot protocol to detect and estimate R loops and show its sensitivity and specificity using the S9.6 antibody. Since specific factors protecting cells from harmful R loop accumulation are expanding, this protocol can be used to determine R loop accumulation in research and clinical settings.
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Affiliation(s)
- Altaf H Sarker
- Department of BioEngineering and BioMedical Sciences, Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - Priscilla K Cooper
- Department of BioEngineering and BioMedical Sciences, Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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36
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Scheuren M, Möhner J, Zischler H. R-loop landscape in mature human sperm: Regulatory and evolutionary implications. Front Genet 2023; 14:1069871. [PMID: 37139234 PMCID: PMC10149866 DOI: 10.3389/fgene.2023.1069871] [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: 10/14/2022] [Accepted: 04/03/2023] [Indexed: 05/05/2023] Open
Abstract
R-loops are three-stranded nucleic acid structures consisting of an RNA:DNA hybrid and a displaced DNA strand. While R-loops pose a potential threat to genome integrity, they constitute 5% of the human genome. The role of R-loops in transcriptional regulation, DNA replication, and chromatin signature is becoming increasingly clear. R-loops are associated with various histone modifications, suggesting that they may modulate chromatin accessibility. To potentially harness transcription-coupled repair mechanisms in the germline, nearly the entire genome is expressed during the early stages of male gametogenesis in mammals, providing ample opportunity for the formation of a transcriptome-dependent R-loop landscape in male germ cells. In this study, our data demonstrated the presence of R-loops in fully mature human and bonobo sperm heads and their partial correspondence to transcribed regions and chromatin structure, which is massively reorganized from mainly histone to mainly protamine-packed chromatin in mature sperm. The sperm R-loop landscape resembles characteristic patterns of somatic cells. Surprisingly, we detected R-loops in both residual histone and protamine-packed chromatin and localize them to still-active retroposons, ALUs and SINE-VNTR-ALUs (SVAs), the latter has recently arisen in hominoid primates. We detected both evolutionarily conserved and species-specific localizations. Comparing our DNA-RNA immunoprecipitation (DRIP) data with published DNA methylation and histone chromatin immunoprecipitation (ChIP) data, we hypothesize that R-loops epigenetically reduce methylation of SVAs. Strikingly, we observe a strong influence of R-loops on the transcriptomes of zygotes from early developmental stages before zygotic genome activation. Overall, these findings suggest that chromatin accessibility influenced by R-loops may represent a system of inherited gene regulation.
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37
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Crossley MP, Song C, Bocek MJ, Choi JH, Kousouros JN, Sathirachinda A, Lin C, Brickner JR, Bai G, Lans H, Vermeulen W, Abu-Remaileh M, Cimprich KA. R-loop-derived cytoplasmic RNA-DNA hybrids activate an immune response. Nature 2023; 613:187-194. [PMID: 36544021 PMCID: PMC9949885 DOI: 10.1038/s41586-022-05545-9] [Citation(s) in RCA: 99] [Impact Index Per Article: 99.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 11/08/2022] [Indexed: 12/24/2022]
Abstract
R-loops are RNA-DNA-hybrid-containing nucleic acids with important cellular roles. Deregulation of R-loop dynamics can lead to DNA damage and genome instability1, which has been linked to the action of endonucleases such as XPG2-4. However, the mechanisms and cellular consequences of such processing have remained unclear. Here we identify a new population of RNA-DNA hybrids in the cytoplasm that are R-loop-processing products. When nuclear R-loops were perturbed by depleting the RNA-DNA helicase senataxin (SETX) or the breast cancer gene BRCA1 (refs. 5-7), we observed XPG- and XPF-dependent cytoplasmic hybrid formation. We identify their source as a subset of stable, overlapping nuclear hybrids with a specific nucleotide signature. Cytoplasmic hybrids bind to the pattern recognition receptors cGAS and TLR3 (ref. 8), activating IRF3 and inducing apoptosis. Excised hybrids and an R-loop-induced innate immune response were also observed in SETX-mutated cells from patients with ataxia oculomotor apraxia type 2 (ref. 9) and in BRCA1-mutated cancer cells10. These findings establish RNA-DNA hybrids as immunogenic species that aberrantly accumulate in the cytoplasm after R-loop processing, linking R-loop accumulation to cell death through the innate immune response. Aberrant R-loop processing and subsequent innate immune activation may contribute to many diseases, such as neurodegeneration and cancer.
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Affiliation(s)
- Magdalena P Crossley
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Chenlin Song
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Michael J Bocek
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Jun-Hyuk Choi
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
- Biometrology Group, Division of Chemical and Biological Metrology, Korea Research Institute of Standards and Science, Daejeon, South Korea
- Department of Bio-Analytical Science, University of Science & Technology, Daejeon, South Korea
| | - Joseph N Kousouros
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Ataya Sathirachinda
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Cindy Lin
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
| | - Joshua R Brickner
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Gongshi Bai
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Hannes Lans
- Department of Molecular Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Wim Vermeulen
- Department of Molecular Genetics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Monther Abu-Remaileh
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
| | - Karlene A Cimprich
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA.
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Hodson C, van Twest S, Dylewska M, O'Rourke JJ, Tan W, Murphy VJ, Walia M, Abbouche L, Nieminuszczy J, Dunn E, Bythell-Douglas R, Heierhorst J, Niedzwiedz W, Deans AJ. Branchpoint translocation by fork remodelers as a general mechanism of R-loop removal. Cell Rep 2022; 41:111749. [PMID: 36476850 DOI: 10.1016/j.celrep.2022.111749] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 10/05/2022] [Accepted: 11/09/2022] [Indexed: 12/12/2022] Open
Abstract
Co-transcriptional R loops arise from stalling of RNA polymerase, leading to the formation of stable DNA:RNA hybrids. Unresolved R loops promote genome instability but are counteracted by helicases and nucleases. Here, we show that branchpoint translocases are a third class of R-loop-displacing enzyme in vitro. In cells, deficiency in the Fanconi-anemia-associated branchpoint translocase FANCM causes R-loop accumulation, particularly after treatment with DNA:RNA-hybrid-stabilizing agents. This correlates with FANCM localization at R-loop-prone regions of the genome. Moreover, other branchpoint translocases associated with human disease, such as SMARCAL1 and ZRANB3, and those from lower organisms can also remove R loops in vitro. Branchpoint translocases are more potent than helicases in resolving R loops, indicating their evolutionary important role in R-loop suppression. In human cells, FANCM, SMARCAL1, and ZRANB3 depletion causes additive effects on R-loop accumulation and DNA damage. Our work reveals a mechanistic basis for R-loop displacement that is linked to genome stability.
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Affiliation(s)
- Charlotte Hodson
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Sylvie van Twest
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | | | - Julienne J O'Rourke
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Winnie Tan
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Vincent J Murphy
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Mannu Walia
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Lara Abbouche
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | | | - Elyse Dunn
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Rohan Bythell-Douglas
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Jörg Heierhorst
- Department of Medicine (St Vincent's Health), University of Melbourne, Fitzroy, VIC 3065, Australia; Molecular Genetics Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | | | - Andrew J Deans
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia; Department of Medicine (St Vincent's Health), University of Melbourne, Fitzroy, VIC 3065, Australia.
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39
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Comprehensive computational analysis of epigenetic descriptors affecting CRISPR-Cas9 off-target activity. BMC Genomics 2022; 23:805. [PMID: 36474180 PMCID: PMC9724382 DOI: 10.1186/s12864-022-09012-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 10/17/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND A common issue in CRISPR-Cas9 genome editing is off-target activity, which prevents the widespread use of CRISPR-Cas9 in medical applications. Among other factors, primary chromatin structure and epigenetics may influence off-target activity. METHODS In this work, we utilize crisprSQL, an off-target database, to analyze the effect of 19 epigenetic descriptors on CRISPR-Cas9 off-target activity. Termed as 19 epigenetic features/scores, they consist of 6 experimental epigenetic and 13 computed nucleosome organization-related features. In terms of novel features, 15 of the epigenetic scores are newly considered. The 15 newly considered scores consist of 13 freshly computed nucleosome occupancy/positioning scores and 2 experimental features (MNase and DRIP). The other 4 existing scores are experimental features (CTCF, DNase I, H3K4me3, RRBS) commonly used in deep learning models for off-target activity prediction. For data curation, MNase was aggregated from existing experimental nucleosome occupancy data. Based on the sequence context information available in crisprSQL, we also computed nucleosome occupancy/positioning scores for off-target sites. RESULTS To investigate the relationship between the 19 epigenetic features and off-target activity, we first conducted Spearman and Pearson correlation analysis. Such analysis shows that some computed scores derived from training-based models and training-free algorithms outperform all experimental epigenetic features. Next, we evaluated the contribution of all epigenetic features in two successful machine/deep learning models which predict off-target activity. We found that some computed scores, unlike all 6 experimental features, significantly contribute to the predictions of both models. As a practical research contribution, we make the off-target dataset containing all 19 epigenetic features available to the research community. CONCLUSIONS Our comprehensive computational analysis helps the CRISPR-Cas9 community better understand the relationship between epigenetic features and CRISPR-Cas9 off-target activity.
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40
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Boleslavska B, Oravetzova A, Shukla K, Nascakova Z, Ibini O, Hasanova Z, Andrs M, Kanagaraj R, Dobrovolna J, Janscak P. DDX17 helicase promotes resolution of R-loop-mediated transcription-replication conflicts in human cells. Nucleic Acids Res 2022; 50:12274-12290. [PMID: 36453994 PMCID: PMC9757067 DOI: 10.1093/nar/gkac1116] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/31/2022] [Accepted: 11/10/2022] [Indexed: 12/02/2022] Open
Abstract
R-loops are three-stranded nucleic acid structures composed of an RNA:DNA hybrid and displaced DNA strand. These structures can halt DNA replication when formed co-transcriptionally in the opposite orientation to replication fork progression. A recent study has shown that replication forks stalled by co-transcriptional R-loops can be restarted by a mechanism involving fork cleavage by MUS81 endonuclease, followed by ELL-dependent reactivation of transcription, and fork religation by the DNA ligase IV (LIG4)/XRCC4 complex. However, how R-loops are eliminated to allow the sequential restart of transcription and replication in this pathway remains elusive. Here, we identified the human DDX17 helicase as a factor that associates with R-loops and counteracts R-loop-mediated replication stress to preserve genome stability. We show that DDX17 unwinds R-loops in vitro and promotes MUS81-dependent restart of R-loop-stalled forks in human cells in a manner dependent on its helicase activity. Loss of DDX17 helicase induces accumulation of R-loops and the formation of R-loop-dependent anaphase bridges and micronuclei. These findings establish DDX17 as a component of the MUS81-LIG4-ELL pathway for resolution of R-loop-mediated transcription-replication conflicts, which may be involved in R-loop unwinding.
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Affiliation(s)
- Barbora Boleslavska
- Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic,Faculty of Science, Charles University in Prague, Albertov 6, 128 00 Prague 2, Czech Republic
| | - Anna Oravetzova
- Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic,Faculty of Science, Charles University in Prague, Albertov 6, 128 00 Prague 2, Czech Republic
| | - Kaustubh Shukla
- Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Zuzana Nascakova
- Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | | | - Zdenka Hasanova
- Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Martin Andrs
- Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Radhakrishnan Kanagaraj
- School of Life Sciences, University of Bedfordshire, Park Square, Luton LU1 3JU, UK,School of Life Sciences, University of Westminster, 115 New Cavendish Street, London W1W 6UW, UK,Centre for Drug Discovery and Development, Sathyabama Institute of Science and Technology, Chennai 600119, India
| | - Jana Dobrovolna
- Correspondence may also be addressed to Jana Dobrovolna. Tel: +420 241063127;
| | - Pavel Janscak
- To whom correspondence should be addressed. Tel: +41 44 6353470;
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41
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Shi X, Teng H, Sun Z. An updated overview of experimental and computational approaches to identify non-canonical DNA/RNA structures with emphasis on G-quadruplexes and R-loops. Brief Bioinform 2022; 23:bbac441. [PMID: 36208174 PMCID: PMC9677470 DOI: 10.1093/bib/bbac441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 08/22/2022] [Accepted: 09/13/2022] [Indexed: 12/14/2022] Open
Abstract
Multiple types of non-canonical nucleic acid structures play essential roles in DNA recombination and replication, transcription, and genomic instability and have been associated with several human diseases. Thus, an increasing number of experimental and bioinformatics methods have been developed to identify these structures. To date, most reviews have focused on the features of non-canonical DNA/RNA structure formation, experimental approaches to mapping these structures, and the association of these structures with diseases. In addition, two reviews of computational algorithms for the prediction of non-canonical nucleic acid structures have been published. One of these reviews focused only on computational approaches for G4 detection until 2020. The other mainly summarized the computational tools for predicting cruciform, H-DNA and Z-DNA, in which the algorithms discussed were published before 2012. Since then, several experimental and computational methods have been developed. However, a systematic review including the conformation, sequencing mapping methods and computational prediction strategies for these structures has not yet been published. The purpose of this review is to provide an updated overview of conformation, current sequencing technologies and computational identification methods for non-canonical nucleic acid structures, as well as their strengths and weaknesses. We expect that this review will aid in understanding how these structures are characterised and how they contribute to related biological processes and diseases.
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Affiliation(s)
- Xiaohui Shi
- Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The first Affiliated Hospital of WMU; Beijing Institutes of Life Science, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Ouhai District, Wenzhou 325000, China
| | - Huajing Teng
- Department of Radiation Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) at Peking University Cancer Hospital and Institute, Ouhai District, Wenzhou 325000, China
| | - Zhongsheng Sun
- Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The first Affiliated Hospital of WMU; Beijing Institutes of Life Science, Chinese Academy of Sciences; CAS Center for Excellence in Biotic Interactions and State Key Laboratory of Integrated Management of Pest Insects and Rodents, University of Chinese Academy of Sciences; Institute of Genomic Medicine, Wenzhou Medical University; IBMC-BGI Center, the Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital); Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Ouhai District, Wenzhou 325000, China
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42
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Koppenhöfer S, Tomasch J, Lang AS. Shared properties of gene transfer agent and core genes revealed by comparative genomics of Alphaproteobacteria. Microb Genom 2022; 8:mgen000890. [PMID: 36350115 PMCID: PMC9836097 DOI: 10.1099/mgen.0.000890] [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] [Indexed: 11/11/2022] Open
Abstract
Gene transfer agents (GTAs) are phage-like particles that transfer pieces of cellular genomic DNA to other cells. Homologues of the Rhodobacter capsulatus GTA (RcGTA) structural genes are widely distributed in the Alphaproteobacteria and particularly well conserved in the order Rhodobacterales. Possible reasons for their widespread conservation are still being discussed. It has been suggested that these alphaproteobacterial elements originate from a prophage that was present in an ancestral bacterium and subsequently evolved into a GTA that is now widely maintained in extant descendant lineages. Here, we analysed genomic properties that might relate to the conservation of these alphaproteobacterial GTAs. This revealed that the chromosomal locations of the GTA gene clusters are biased. They primarily occur on the leading strand of DNA replication, at large distances from long repetitive elements, and thus are in regions of lower plasticity, and in areas of extreme GC skew, which also accumulate core genes. These extreme GC skew regions arise from the preferential use of codons with an excess of G over C, a distinct phenomenon from the elevated GC content that has previously been found to be associated with GTA genes. The observed properties, along with their high level of conservation, show that GTA genes share multiple features with core genes in the examined lineages of the Alphaproteobacteria.
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Affiliation(s)
- Sonja Koppenhöfer
- Department of Biology, Memorial University of Newfoundland, St John’s, Newfoundland and Labrador, Canada
| | - Jürgen Tomasch
- Laboratory of Anoxygenic Phototrophs, Institute of Microbiology of the Czech Academy of Science – Centre Algatech, Třeboň, Czech Republic
| | - Andrew S. Lang
- Department of Biology, Memorial University of Newfoundland, St John’s, Newfoundland and Labrador, Canada,*Correspondence: Andrew S. Lang,
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43
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Fong N, Sheridan RM, Ramachandran S, Bentley DL. The pausing zone and control of RNA polymerase II elongation by Spt5: Implications for the pause-release model. Mol Cell 2022; 82:3632-3645.e4. [PMID: 36206739 PMCID: PMC9555879 DOI: 10.1016/j.molcel.2022.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 07/24/2022] [Accepted: 08/31/2022] [Indexed: 11/07/2022]
Abstract
The pause-release model of transcription proposes that 40-100 bases from the start site RNA Pol II pauses, followed by release into productive elongation. Pause release is facilitated by the PTEFb phosphorylation of the RNA Pol II elongation factor, Spt5. We mapped paused polymerases by eNET-seq and found frequent pausing in zones that extend ∼0.3-3 kb into genes even when PTEFb is inhibited. The fraction of paused polymerases or pausing propensity declines gradually over several kb and not abruptly as predicted for a discrete pause-release event. Spt5 depletion extends pausing zones, suggesting that it promotes the maturation of elongation complexes to a low-pausing state. The expression of mutants after Spt5 depletion showed that phosphomimetic substitutions in the CTR1 domain diminished pausing throughout genes. By contrast, mutants that prevent the phosphorylation of the Spt5 RNA-binding domain strengthened pausing. Thus, distinct Spt5 phospho-isoforms set the balance between pausing and elongation.
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Affiliation(s)
- Nova Fong
- RNA Bioscience Initiative, Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA
| | - Ryan M Sheridan
- RNA Bioscience Initiative, Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA
| | - Srinivas Ramachandran
- RNA Bioscience Initiative, Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA
| | - David L Bentley
- RNA Bioscience Initiative, Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA.
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44
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Groelly FJ, Dagg RA, Petropoulos M, Rossetti GG, Prasad B, Panagopoulos A, Paulsen T, Karamichali A, Jones SE, Ochs F, Dionellis VS, Puig Lombardi E, Miossec MJ, Lockstone H, Legube G, Blackford AN, Altmeyer M, Halazonetis TD, Tarsounas M. Mitotic DNA synthesis is caused by transcription-replication conflicts in BRCA2-deficient cells. Mol Cell 2022; 82:3382-3397.e7. [PMID: 36002001 PMCID: PMC9631240 DOI: 10.1016/j.molcel.2022.07.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/31/2022] [Accepted: 07/16/2022] [Indexed: 12/24/2022]
Abstract
Aberrant replication causes cells lacking BRCA2 to enter mitosis with under-replicated DNA, which activates a repair mechanism known as mitotic DNA synthesis (MiDAS). Here, we identify genome-wide the sites where MiDAS reactions occur when BRCA2 is abrogated. High-resolution profiling revealed that these sites are different from MiDAS at aphidicolin-induced common fragile sites in that they map to genomic regions replicating in the early S-phase, which are close to early-firing replication origins, are highly transcribed, and display R-loop-forming potential. Both transcription inhibition in early S-phase and RNaseH1 overexpression reduced MiDAS in BRCA2-deficient cells, indicating that transcription-replication conflicts (TRCs) and R-loops are the source of MiDAS. Importantly, the MiDAS sites identified in BRCA2-deficient cells also represent hotspots for genomic rearrangements in BRCA2-mutated breast tumors. Thus, our work provides a mechanism for how tumor-predisposing BRCA2 inactivation links transcription-induced DNA damage with mitotic DNA repair to fuel the genomic instability characteristic of cancer cells.
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Affiliation(s)
- Florian J Groelly
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Rebecca A Dagg
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | | | - Giacomo G Rossetti
- Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland
| | - Birbal Prasad
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Andreas Panagopoulos
- Department of Molecular Mechanisms of Disease, University of Zurich, 8057 Zurich, Switzerland
| | - Teressa Paulsen
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | | | - Samuel E Jones
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Fena Ochs
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Vasilis S Dionellis
- Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland
| | - Emilia Puig Lombardi
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Matthieu J Miossec
- Bioinformatics and Statistical Genetics Core, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Helen Lockstone
- Bioinformatics and Statistical Genetics Core, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Gaëlle Legube
- LBCMCP, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse 31062, France
| | - Andrew N Blackford
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich, 8057 Zurich, Switzerland
| | - Thanos D Halazonetis
- Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland.
| | - Madalena Tarsounas
- Genome Stability and Tumourigenesis Group, Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK.
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45
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Abstract
Enhancers confer precise spatiotemporal patterns of gene expression in response to developmental and environmental stimuli. Over the last decade, the transcription of enhancer RNAs (eRNAs) – nascent RNAs transcribed from active enhancers – has emerged as a key factor regulating enhancer activity. eRNAs are relatively short-lived RNA species that are transcribed at very high rates but also quickly degraded. Nevertheless, eRNAs are deeply intertwined within enhancer regulatory networks and are implicated in a number of transcriptional control mechanisms. Enhancers show changes in function and sequence over evolutionary time, raising questions about the relationship between enhancer sequences and eRNA function. Moreover, the vast majority of single nucleotide polymorphisms associated with human complex diseases map to the non-coding genome, with causal disease variants enriched within enhancers. In this Primer, we survey the diverse roles played by eRNAs in enhancer-dependent gene expression, evaluating different models for eRNA function. We also explore questions surrounding the genetic conservation of enhancers and how this relates to eRNA function and dysfunction. Summary: This Primer evaluates the ideas that underpin developing models for eRNA function, exploring cases in which perturbed eRNA function contributes to disease.
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Affiliation(s)
- Laura J. Harrison
- Molecular and Cellular Biology, School of Biosciences, Sheffield Institute For Nucleic Acids, The University of Sheffield, Firth Court, Western Bank , Sheffield S10 2TN , UK
| | - Daniel Bose
- Molecular and Cellular Biology, School of Biosciences, Sheffield Institute For Nucleic Acids, The University of Sheffield, Firth Court, Western Bank , Sheffield S10 2TN , UK
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46
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Thongthip S, Carlson A, Crossley MP, Schwer B. Relationships between genome-wide R-loop distribution and classes of recurrent DNA breaks in neural stem/progenitor cells. Sci Rep 2022; 12:13373. [PMID: 35927309 PMCID: PMC9352722 DOI: 10.1038/s41598-022-17452-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 07/26/2022] [Indexed: 11/09/2022] Open
Abstract
Recent studies revealed classes of recurrent DNA double-strand breaks (DSBs) in neural stem/progenitor cells, including transcription-associated, promoter-proximal breaks and recurrent DSB clusters in late-replicating, long neural genes that may give rise to somatic brain mosaicism. The mechanistic factors promoting these different classes of DSBs in neural stem/progenitor cells are not understood. Here, we elucidated the genome-wide landscape of RNA:DNA hybrid structures called “R-loops” in primary neural stem/progenitor cells undergoing aphidicolin-induced, mild replication stress to assess the potential contribution of R-loops to the different, recurrent classes of DNA break “hotspots”. We find that R-loops in neural stem/progenitor cells undergoing mild replication stress are present primarily in early-replicating, transcribed regions and in genes with promoter GC skew that are associated with cell lineage-specific processes. Surprisingly, most long, neural genes that form recurrent DSB clusters do not show R-loop formation under conditions of mild replication stress. Our findings are consistent with a role of R-loop-associated processes in promoter-proximal DNA break formation in highly transcribed, early replicating regions but suggest that R-loops do not drive replication stress-induced, recurrent DSB cluster formation in most long, neural genes.
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Affiliation(s)
- Supawat Thongthip
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA, USA.,Weill Institute for Neuroscience, University of California, San Francisco, CA, USA.,Department of Neurological Surgery, University of California, San Francisco, CA, USA
| | - Annika Carlson
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA, USA.,Weill Institute for Neuroscience, University of California, San Francisco, CA, USA.,Department of Neurological Surgery, University of California, San Francisco, CA, USA
| | - Magdalena P Crossley
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Bjoern Schwer
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA, USA. .,Bakar Aging Research Institute, University of California, San Francisco, CA, USA. .,Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, CA, USA. .,Weill Institute for Neuroscience, University of California, San Francisco, CA, USA. .,Department of Neurological Surgery, University of California, San Francisco, CA, USA.
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47
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Kumar A, Fournier LA, Stirling PC. Integrative analysis and prediction of human R-loop binding proteins. G3 (BETHESDA, MD.) 2022; 12:jkac142. [PMID: 35666183 PMCID: PMC9339281 DOI: 10.1093/g3journal/jkac142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
In the past decade, there has been a growing appreciation for R-loop structures as important regulators of the epigenome, telomere maintenance, DNA repair, and replication. Given these numerous functions, dozens, or potentially hundreds, of proteins could serve as direct or indirect regulators of R-loop writing, reading, and erasing. In order to understand common properties shared amongst potential R-loop binding proteins, we mined published proteomic studies and distilled 10 features that were enriched in R-loop binding proteins compared with the rest of the proteome. Applying an easy-ensemble machine learning approach, we used these R-loop binding protein-specific features along with their amino acid composition to create random forest classifiers that predict the likelihood of a protein to bind to R-loops. Known R-loop regulating pathways such as splicing, DNA damage repair and chromatin remodeling are highly enriched in our datasets, and we validate 2 new R-loop binding proteins LIG1 and FXR1 in human cells. Together these datasets provide a reference to pursue analyses of novel R-loop regulatory proteins.
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Affiliation(s)
| | | | - Peter C Stirling
- Corresponding author: Terry Fox Laboratory, BC Cancer, Vancouver, BC V5Z1L3, Canada.
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48
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Miller HE, Montemayor D, Abdul J, Vines A, Levy SA, Hartono SR, Sharma K, Frost B, Chédin F, Bishop AJR. Quality-controlled R-loop meta-analysis reveals the characteristics of R-loop consensus regions. Nucleic Acids Res 2022; 50:7260-7286. [PMID: 35758606 PMCID: PMC9303298 DOI: 10.1093/nar/gkac537] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 06/16/2022] [Indexed: 12/13/2022] Open
Abstract
R-loops are three-stranded nucleic acid structures formed from the hybridization of RNA and DNA. While the pathological consequences of R-loops have been well-studied to date, the locations, classes, and dynamics of physiological R-loops remain poorly understood. R-loop mapping studies provide insight into R-loop dynamics, but their findings are challenging to generalize. This is due to the narrow biological scope of individual studies, the limitations of each mapping modality, and, in some cases, poor data quality. In this study, we reprocessed 810 R-loop mapping datasets from a wide array of biological conditions and mapping modalities. From this data resource, we developed an accurate R-loop data quality control method, and we reveal the extent of poor-quality data within previously published studies. We then identified a set of high-confidence R-loop mapping samples and used them to define consensus R-loop sites called 'R-loop regions' (RL regions). In the process, we identified a stark divergence between RL regions detected by S9.6 and dRNH-based mapping methods, particularly with respect to R-loop size, location, and colocalization with RNA binding factors. Taken together, this work provides a much-needed method to assess R-loop data quality and offers novel context regarding the differences between dRNH- and S9.6-based R-loop mapping approaches.
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Affiliation(s)
- Henry E Miller
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX, USA.,Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, TX, USA.,Bioinformatics Research Network, Atlanta, GA, USA
| | - Daniel Montemayor
- Department of Medicine, UT Health San Antonio, San Antonio, TX, USA.,Center for Precision Medicine, UT Health San Antonio, San Antonio, TX, USA
| | - Jebriel Abdul
- Bioinformatics Research Network, Atlanta, GA, USA.,Department of Biology, University of Ottawa, Ottawa, Canada
| | - Anna Vines
- Bioinformatics Research Network, Atlanta, GA, USA.,Faculty of Arts, University of Bristol, Bristol, U.K
| | - Simon A Levy
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX, USA.,Bioinformatics Research Network, Atlanta, GA, USA.,Sam & Ann Barshop Institute for Longevity & Aging Studies, UT Health San Antonio, San Antonio, TX, USA.,Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX, USA
| | - Stella R Hartono
- Department of Molecular and Cellular Biology, UC Davis, Davis, CA, USA
| | - Kumar Sharma
- Department of Medicine, UT Health San Antonio, San Antonio, TX, USA.,Center for Precision Medicine, UT Health San Antonio, San Antonio, TX, USA
| | - Bess Frost
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX, USA.,Sam & Ann Barshop Institute for Longevity & Aging Studies, UT Health San Antonio, San Antonio, TX, USA.,Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, UT Health San Antonio, San Antonio, TX, USA
| | - Frédéric Chédin
- Department of Molecular and Cellular Biology, UC Davis, Davis, CA, USA
| | - Alexander J R Bishop
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX, USA.,Greehey Children's Cancer Research Institute, UT Health San Antonio, San Antonio, TX, USA.,May's Cancer Center, UT Health San Antonio, San Antonio, TX, USA
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49
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Pan X, Huang LF. Multi-omics to characterize the functional relationships of R-loops with epigenetic modifications, RNAPII transcription and gene expression. Brief Bioinform 2022; 23:6618633. [DOI: 10.1093/bib/bbac238] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 05/19/2022] [Accepted: 05/21/2022] [Indexed: 12/12/2022] Open
Abstract
Abstract
Abnormal accumulation of R-loops results in replication stress, genome instability, chromatin alterations and gene silencing. Little research has been done to characterize functional relationships among R-loops, histone marks, RNA polymerase II (RNAPII) transcription and gene regulation. We built extremely randomized trees (ETs) models to predict the genome-wide R-loops using RNAPII and multiple histone modifications chromatin immunoprecipitation (ChIP)-seq, DNase-seq, Global Run-On sequencing (GRO-seq) and R-loop profiling data. We compared the performance of ET models to multiple machine learning approaches, and the proposed ET models achieved the best and extremely robust performances. Epigenetic profiles are highly predictive of R-loops genome-widely and they are strongly associated with R-loop formation. In addition, the presence of R-loops is significantly correlated with RNAPII transcription activity, H3K4me3 and open chromatin around the transcription start site, and H3K9me1 and H3K9me3 around the transcription termination site. RNAPII pausing defects were correlated with 5′R-loops accumulation, and transcriptional termination defects and read-throughs were correlated with 3′R-loops accumulation. Furthermore, we found driver genes with 5′R-loops and RNAPII pausing defects express significantly higher and genes with 3′R-loops and read-through transcription express significantly lower than genes without R-loops. These driver genes are enriched with chromosomal instability, Hippo–Merlin signaling Dysregulation, DNA damage response and TGF-β pathways, indicating R-loops accumulating at the 5′ end of genes play oncogenic roles, whereas at the 3′ end of genes play tumor-suppressive roles in tumorigenesis.
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Affiliation(s)
- Xingxin Pan
- Division of Experimental Hematology and Cancer Biology , Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229 , USA
| | - L Frank Huang
- Division of Experimental Hematology and Cancer Biology , Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229 , USA
- Department of Pediatrics, University of Cincinnati College of Medicine , Cincinnati, OH 45229 , USA
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50
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Wang Y, Ma B, Liu X, Gao G, Che Z, Fan M, Meng S, Zhao X, Sugimura R, Cao H, Zhou Z, Xie J, Lin C, Luo Z. ZFP281-BRCA2 prevents R-loop accumulation during DNA replication. Nat Commun 2022; 13:3493. [PMID: 35715464 PMCID: PMC9205938 DOI: 10.1038/s41467-022-31211-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 06/08/2022] [Indexed: 11/16/2022] Open
Abstract
R-loops are prevalent in mammalian genomes and involved in many fundamental cellular processes. Depletion of BRCA2 leads to aberrant R-loop accumulation, contributing to genome instability. Here, we show that ZFP281 cooperates with BRCA2 in preventing R-loop accumulation to facilitate DNA replication in embryonic stem cells. ZFP281 depletion reduces PCNA levels on chromatin and impairs DNA replication. Mechanistically, we demonstrate that ZFP281 can interact with BRCA2, and that BRCA2 is enriched at G/C-rich promoters and requires both ZFP281 and PRC2 for its proper recruitment to the bivalent chromatin at the genome-wide scale. Furthermore, depletion of ZFP281 or BRCA2 leads to accumulation of R-loops over the bivalent regions, and compromises activation of the developmental genes by retinoic acid during stem cell differentiation. In summary, our results reveal that ZFP281 recruits BRCA2 to the bivalent chromatin regions to ensure proper progression of DNA replication through preventing persistent R-loops. R-loops are prevalent in mammalian genomes and involved in many fundamental cellular processes. Here, Wang et al. report that ZFP281 cooperates with BRCA2 in preventing R-loop accumulation to facilitate DNA replication in embryonic stem cells.
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Affiliation(s)
- Yan Wang
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Binbin Ma
- Institute for Regenerative Medicine, Shanghai East Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Xiaoxu Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Ge Gao
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, 999077, China
| | - Zhuanzhuan Che
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Menghan Fan
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Siyan Meng
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Xiru Zhao
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China
| | - Rio Sugimura
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, 999077, China
| | - Hua Cao
- Key Laboratory of Technical Evaluation of Fertility Regulation of Non-human primate, Fujian Provincial Maternity and Children's Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, China
| | - Zhongjun Zhou
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong, 999077, China
| | - Jing Xie
- Institute for Regenerative Medicine, Shanghai East Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Chengqi Lin
- Key Laboratory of Technical Evaluation of Fertility Regulation of Non-human primate, Fujian Provincial Maternity and Children's Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, China. .,Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China. .,Shenzhen Research Institute, Southeast University, 19 Gaoxin South 4th Road, Nanshan District, Shenzhen, 518063, China.
| | - Zhuojuan Luo
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China. .,Shenzhen Research Institute, Southeast University, 19 Gaoxin South 4th Road, Nanshan District, Shenzhen, 518063, China.
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