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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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2
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Bergis-Ser C, Reji M, Latrasse D, Bergounioux C, Benhamed M, Raynaud C. Chromatin dynamics and RNA metabolism are double-edged swords for the maintenance of plant genome integrity. NATURE PLANTS 2024; 10:857-873. [PMID: 38658791 DOI: 10.1038/s41477-024-01678-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 03/27/2024] [Indexed: 04/26/2024]
Abstract
Maintenance of genome integrity is an essential process in all organisms. Mechanisms avoiding the formation of DNA lesions or mutations are well described in animals because of their relevance to human health and cancer. In plants, they are of growing interest because DNA damage accumulation is increasingly recognized as one of the consequences of stress. Although the cellular response to DNA damage is mostly studied in response to genotoxic treatments, the main source of DNA lesions is cellular activity itself. This can occur through the production of reactive oxygen species as well as DNA processing mechanisms such as DNA replication or transcription and chromatin dynamics. In addition, how lesions are formed and repaired is greatly influenced by chromatin features and dynamics and by DNA and RNA metabolism. Notably, actively transcribed regions or replicating DNA, because they are less condensed and are sites of DNA processing, are more exposed to DNA damage. However, at the same time, a wealth of cellular mechanisms cooperate to favour DNA repair at these genomic loci. These intricate relationships that shape the distribution of mutations along the genome have been studied extensively in animals but much less in plants. In this Review, we summarize how chromatin dynamics influence lesion formation and DNA repair in plants, providing a comprehensive view of current knowledge and highlighting open questions with regard to what is known in other organisms.
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Affiliation(s)
- Clara Bergis-Ser
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay, Orsay, France
| | - Meega Reji
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay, Orsay, France
- Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, India
| | - David Latrasse
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay, Orsay, France
| | - Catherine Bergounioux
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay, Orsay, France
| | - Moussa Benhamed
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay, Orsay, France
- Université Paris Cité, Institute of Plant Sciences Paris-Saclay, Gif-sur-Yvette, France
- Institut Universitaire de France, Orsay, France
| | - Cécile Raynaud
- Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay, Orsay, France.
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3
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Schmid LM, Manavski N, Chi W, Meurer J. Chloroplast Ribosome Biogenesis Factors. PLANT & CELL PHYSIOLOGY 2024; 65:516-536. [PMID: 37498958 DOI: 10.1093/pcp/pcad082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/13/2023] [Accepted: 07/25/2023] [Indexed: 07/29/2023]
Abstract
The formation of chloroplasts can be traced back to an ancient event in which a eukaryotic host cell containing mitochondria ingested a cyanobacterium. Since then, chloroplasts have retained many characteristics of their bacterial ancestor, including their transcription and translation machinery. In this review, recent research on the maturation of rRNA and ribosome assembly in chloroplasts is explored, along with their crucial role in plant survival and their implications for plant acclimation to changing environments. A comparison is made between the ribosome composition and auxiliary factors of ancient and modern chloroplasts, providing insights into the evolution of ribosome assembly factors. Although the chloroplast contains ancient proteins with conserved functions in ribosome assembly, newly evolved factors have also emerged to help plants acclimate to changes in their environment and internal signals. Overall, this review offers a comprehensive analysis of the molecular mechanisms underlying chloroplast ribosome assembly and highlights the importance of this process in plant survival, acclimation and adaptation.
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Affiliation(s)
- Lisa-Marie Schmid
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, Planegg-Martinsried 82152, Germany
| | - Nikolay Manavski
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, Planegg-Martinsried 82152, Germany
| | - Wei Chi
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jörg Meurer
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University Munich, Großhaderner Street 2-4, Planegg-Martinsried 82152, Germany
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4
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Nishimura Y. Plastid Nucleoids: Insights into Their Shape and Dynamics. PLANT & CELL PHYSIOLOGY 2024; 65:551-559. [PMID: 37542434 DOI: 10.1093/pcp/pcad090] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/26/2023] [Accepted: 08/04/2023] [Indexed: 08/07/2023]
Abstract
Chloroplasts/plastids are unique organelles found in plant cells and some algae and are responsible for performing essential functions such as photosynthesis. The plastid genome, consisting of circular and linear DNA molecules, is packaged and organized into specialized structures called nucleoids. The composition and dynamics of these nucleoids have been the subject of intense research, as they are critical for proper plastid functions and development. In this mini-review, recent advances in understanding the organization and regulation of plastid nucleoids are overviewed, with a focus on the various proteins and factors that regulate the shape and dynamics of nucleoids, including DNA-binding proteins and membrane anchorage proteins. The dynamic nature of nucleoid organization, which is influenced by a variety of developmental cues and the cell cycle, is also examined.
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Affiliation(s)
- Yoshiki Nishimura
- Department of Botany, Graduate School of Science, Kyoto University, Oiwake-cho, Kita-Shirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
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5
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Bai X, Zhang R, Zeng Q, Yang W, Fang F, Sun Q, Yan C, Li F, Liu X, Li B. The RNA-Binding Protein BoRHON1 Positively Regulates the Accumulation of Aliphatic Glucosinolates in Cabbage. Int J Mol Sci 2024; 25:5314. [PMID: 38791354 PMCID: PMC11120748 DOI: 10.3390/ijms25105314] [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: 03/23/2024] [Revised: 04/29/2024] [Accepted: 05/11/2024] [Indexed: 05/26/2024] Open
Abstract
Aliphatic glucosinolates are an abundant group of plant secondary metabolites in Brassica vegetables, with some of their degradation products demonstrating significant anti-cancer effects. The transcription factors MYB28 and MYB29 play key roles in the transcriptional regulation of aliphatic glucosinolates biosynthesis, but little is known about whether BoMYB28 and BoMYB29 are also modulated by upstream regulators or how, nor their gene regulatory networks. In this study, we first explored the hierarchical transcriptional regulatory networks of MYB28 and MYB29 in a model plant, then systemically screened the regulators of the three BoMYB28 homologs in cabbage using a yeast one-hybrid. Furthermore, we selected a novel RNA binding protein, BoRHON1, to functionally validate its roles in modulating aliphatic glucosinolates biosynthesis. Importantly, BoRHON1 induced the accumulation of all detectable aliphatic and indolic glucosinolates, and the net photosynthetic rates of BoRHON1 overexpression lines were significantly increased. Interestingly, the growth and biomass of these overexpression lines of BoRHON1 remained the same as those of the control plants. BoRHON1 was shown to be a novel, potent, positive regulator of glucosinolates biosynthesis, as well as a novel regulator of normal plant growth and development, while significantly increasing plants' defense costs.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Baohua Li
- State Key Laboratory of Crop Stress Biology for Arid Area, College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China; (X.B.); (R.Z.); (Q.Z.); (W.Y.); (F.F.); (Q.S.); (C.Y.); (F.L.); (X.L.)
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6
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Bhatt U, Cucchiarini A, Luo Y, Evans CW, Mergny JL, Iyer KS, Smith NM. Preferential formation of Z-RNA over intercalated motifs in long noncoding RNA. Genome Res 2024; 34:217-230. [PMID: 38355305 PMCID: PMC10984386 DOI: 10.1101/gr.278236.123] [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: 06/30/2023] [Accepted: 01/31/2024] [Indexed: 02/16/2024]
Abstract
Secondary structure is a principal determinant of lncRNA function, predominantly regarding scaffold formation and interfaces with target molecules. Noncanonical secondary structures that form in nucleic acids have known roles in regulating gene expression and include G-quadruplexes (G4s), intercalated motifs (iMs), and R-loops (RLs). In this paper, we used the computational tools G4-iM Grinder and QmRLFS-finder to predict the formation of each of these structures throughout the lncRNA transcriptome in comparison to protein-coding transcripts. The importance of the predicted structures in lncRNAs in biological contexts was assessed by combining our results with publicly available lncRNA tissue expression data followed by pathway analysis. The formation of predicted G4 (pG4) and iM (piM) structures in select lncRNA sequences was confirmed in vitro using biophysical experiments under near-physiological conditions. We find that the majority of the tested pG4s form highly stable G4 structures, and identify many previously unreported G4s in biologically important lncRNAs. In contrast, none of the piM sequences are able to form iM structures, consistent with the idea that RNA is unable to form stable iMs. Unexpectedly, these C-rich sequences instead form Z-RNA structures, which have not been previously observed in regions containing cytosine repeats and represent an interesting and underexplored target for protein-RNA interactions. Our results highlight the prevalence and potential structure-associated functions of noncanonical secondary structures in lncRNAs, and show G4 and Z-RNA structure formation in many lncRNA sequences for the first time, furthering the understanding of the structure-function relationship in lncRNAs.
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Affiliation(s)
- Uditi Bhatt
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Anne Cucchiarini
- Laboratoire d'Optique et Biosciences, École Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91120 Palaiseau, France
| | - Yu Luo
- Laboratoire d'Optique et Biosciences, École Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91120 Palaiseau, France
| | - Cameron W Evans
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Jean-Louis Mergny
- Laboratoire d'Optique et Biosciences, École Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91120 Palaiseau, France
| | - K Swaminathan Iyer
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Nicole M Smith
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia;
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7
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Chai X, Wang X, Rong L, Luo M, Yuan L, Li Q, He B, Jiang J, Ji D, Ouyang M, Lu Q, Zhang L, Rochaix JD, Chi W. The translocon protein FtsHi1 is an ATP-dependent DNA/RNA helicase that prevents R-loop accumulation in chloroplasts. THE NEW PHYTOLOGIST 2024; 241:2209-2226. [PMID: 38084045 DOI: 10.1111/nph.19470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 11/22/2023] [Indexed: 02/09/2024]
Abstract
R-loops, three-stranded nucleic acid structures consisting of a DNA: RNA hybrid and displaced single-stranded DNA, play critical roles in gene expression and genome stability. How R-loop homeostasis is integrated into chloroplast gene expression remains largely unknown. We found an unexpected function of FtsHi1, an inner envelope membrane-bound AAA-ATPase in chloroplast R-loop homeostasis of Arabidopsis thaliana. Previously, this protein was shown to function as a component of the import motor complex for nuclear-encoded chloroplast proteins. However, this study provides evidence that FtsHi1 is an ATP-dependent helicase that efficiently unwinds both DNA-DNA and DNA-RNA duplexes, thereby preventing R-loop accumulation. Over-accumulation of R-loops could impair chloroplast transcription but not necessarily genome integrity. The dual function of FtsHi1 in both protein import and chloroplast gene expression may be important to coordinate the biogenesis of nuclear- and chloroplast-encoded subunits of multi-protein photosynthetic complexes. This study suggests a mechanical link between protein import and R-loop homeostasis in chloroplasts of higher plants.
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Affiliation(s)
- Xin Chai
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Artemisinin Research Center, Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Xiushun Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Liwei Rong
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Manfei Luo
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Li Yuan
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qiuxin Li
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Baoye He
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Jingjing Jiang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Daili Ji
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Min Ouyang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Qingtao Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Lixin Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, 85 Minglun St., Kaifeng, 475001, China
| | - Jean-David Rochaix
- Department of Molecular Biology, University of Geneva, 1211, Geneva, Switzerland
- Department of Plant Biology, University of Geneva, 1211, Geneva, Switzerland
| | - Wei Chi
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
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8
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Zhang W, Yang Z, Wang W, Sun Q. Primase promotes the competition between transcription and replication on the same template strand resulting in DNA damage. Nat Commun 2024; 15:73. [PMID: 38168108 PMCID: PMC10761990 DOI: 10.1038/s41467-023-44443-0] [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: 06/20/2023] [Accepted: 12/13/2023] [Indexed: 01/05/2024] Open
Abstract
Transcription-replication conflicts (TRCs), especially Head-On TRCs (HO-TRCs) can introduce R-loops and DNA damage, however, the underlying mechanisms are still largely unclear. We previously identified a chloroplast-localized RNase H1 protein AtRNH1C that can remove R-loops and relax HO-TRCs for genome integrity. Through the mutagenesis screen, we identify a mutation in chloroplast-localized primase ATH that weakens the binding affinity of DNA template and reduces the activities of RNA primer synthesis and delivery. This slows down DNA replication, and reduces competition of transcription-replication, thus rescuing the developmental defects of atrnh1c. Strand-specific DNA damage sequencing reveals that HO-TRCs cause DNA damage at the end of the transcription unit in the lagging strand and overexpression of ATH can boost HO-TRCs and exacerbates DNA damage. Furthermore, mutation of plastid DNA polymerase Pol1A can similarly rescue the defects in atrnh1c mutants. Taken together these results illustrate a potentially conserved mechanism among organisms, of which the primase activity can promote the occurrence of transcription-replication conflicts leading to HO-TRCs and genome instability.
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Affiliation(s)
- Weifeng Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, China
- Tsinghua-Peking Center for Life Sciences, 100084, Beijing, China
| | - Zhuo Yang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, China
- Tsinghua-Peking Center for Life Sciences, 100084, Beijing, China
| | - Wenjie Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, China
- Tsinghua-Peking Center for Life Sciences, 100084, Beijing, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, China.
- Tsinghua-Peking Center for Life Sciences, 100084, Beijing, China.
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9
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He Z, Li M, Pan X, Peng Y, Shi Y, Han Q, Shi M, She L, Borovskii G, Chen X, Gu X, Cheng X, Zhang W. R-loops act as regulatory switches modulating transcription of COLD-responsive genes in rice. THE NEW PHYTOLOGIST 2024; 241:267-282. [PMID: 37849024 DOI: 10.1111/nph.19315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 09/22/2023] [Indexed: 10/19/2023]
Abstract
COLD is a major naturally occurring stress that usually causes complex symptoms and severe yield loss in crops. R-loops function in various cellular processes, including development and stress responses, in plants. However, how R-loops function in COLD responses is largely unknown in COLD susceptible crops like rice (Oryza sativa L.). We conducted DRIP-Seq along with other omics data (RNA-Seq, DNase-Seq and ChIP-Seq) in rice with or without COLD treatment. COLD treatment caused R-loop reprogramming across the genome. COLD-biased R-loops had higher GC content and novel motifs for the binding of distinct transcription factors (TFs). Moreover, R-loops can directly/indirectly modulate the transcription of a subset of COLD-responsive genes, which can be mediated by R-loop overlapping TF-centered or cis-regulatory element-related regulatory networks and lncRNAs, accounting for c. 60% of COLD-induced expression of differential genes in rice, which is different from the findings in Arabidopsis. We validated two R-loop loci with contrasting (negative/positive) roles in the regulation of two individual COLD-responsive gene expression, as potential targets for enhanced COLD resistance. Our study provides detailed evidence showing functions of R-loop reprogramming during COLD responses and provides some potential R-loop loci for genetic and epigenetic manipulation toward breeding of rice varieties with enhanced COLD tolerance.
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Affiliation(s)
- Zexue He
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Mengqi Li
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Xiucai Pan
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
- Xiangyang Academy of Agricultural Sciences, Xiangyang, Hubei Province, 441057, China
| | - Yulian Peng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Yining Shi
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Qi Han
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Manli Shi
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Linwei She
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Gennadii Borovskii
- Siberian Institute of Plant Physiology and Biochemistry, Siberian Branch of Russian Academy of Sciences (SB RAS) Irkutsk, Lermontova, 664033, Russia
| | - Xiaojun Chen
- Key Lab of Agricultural Biotechnology of Ningxia, Ningxia Academy of Agriculture and Forestry Sciences, YinChuan, 750002, China
| | - Xiaofeng Gu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xuejiao Cheng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
| | - Wenli Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production Co-Sponsored by Province and Ministry (CIC-MCP), Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, China
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10
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Li Q, Zhou J, Li S, Zhang W, Du Y, Li K, Wang Y, Sun Q. DNA polymerase ε harmonizes topological states and R-loops formation to maintain genome integrity in Arabidopsis. Nat Commun 2023; 14:7763. [PMID: 38012183 PMCID: PMC10682485 DOI: 10.1038/s41467-023-43680-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 11/16/2023] [Indexed: 11/29/2023] Open
Abstract
Genome topology is tied to R-loop formation and genome stability. However, the regulatory mechanism remains to be elucidated. By establishing a system to sense the connections between R-loops and genome topology states, we show that inhibiting DNA topoisomerase 1 (TOP1i) triggers the global increase of R-loops (called topoR-loops) and DNA damages, which are exacerbated in the DNA damage repair-compromised mutant atm. A suppressor screen identifies a mutation in POL2A, the catalytic subunit of DNA polymerase ε, rescuing the TOP1i-induced topoR-loop accumulation and genome instability in atm. Importantly we find that a highly conserved junction domain between the exonuclease and polymerase domains in POL2A is required for modulating topoR-loops near DNA replication origins and facilitating faithful DNA replication. Our results suggest that DNA replication acts in concert with genome topological states to fine-tune R-loops and thereby maintain genome integrity, revealing a likely conserved regulatory mechanism of TOP1i resistance in chemotherapy for ATM-deficient cancers.
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Affiliation(s)
- Qin Li
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jincong Zhou
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Shuai Li
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Weifeng Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Yingxue Du
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Kuan Li
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
- Chinese Institute for Brain Research, Beijing, 102206, China
| | - Yingxiang Wang
- College of Life Science, South China Agricultural University, Guangdong Laboratory for Lingnan Morden Agriculture, Guangzhou, 510642, China
- State Key Laboratory of Genetic Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China.
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11
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Tripathi D, Oldenburg DJ, Bendich AJ. Ribonucleotide and R-Loop Damage in Plastid DNA and Mitochondrial DNA during Maize Development. PLANTS (BASEL, SWITZERLAND) 2023; 12:3161. [PMID: 37687407 PMCID: PMC10489836 DOI: 10.3390/plants12173161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/29/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023]
Abstract
Although the temporary presence of ribonucleotides in DNA is normal, their persistence represents a form of DNA damage. Here, we assess such damage and damage defense to DNA in plastids and mitochondria of maize. Shoot development proceeds from meristematic, non-pigmented cells containing proplastids and promitochondria at the leaf base to non-dividing green cells in the leaf blade containing mature organelles. The organellar DNAs (orgDNAs) become fragmented during this transition. Previously, orgDNA damage and damage defense of two types, oxidative and glycation, was described in maize, and now a third type, ribonucleotide damage, is reported. We hypothesized that ribonucleotide damage changes during leaf development and could contribute to the demise of orgDNAs. The levels of ribonucleotides and R-loops in orgDNAs and of RNase H proteins in organelles were measured throughout leaf development and in leaves grown in light and dark conditions. The data reveal that ribonucleotide damage to orgDNAs increased by about 2- to 5-fold during normal maize development from basal meristem to green leaf and when leaves were grown in normal light conditions compared to in the dark. During this developmental transition, the levels of the major agent of defense, RNase H, declined. The decline in organellar genome integrity during maize development may be attributed to oxidative, glycation, and ribonucleotide damages that are not repaired.
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Affiliation(s)
| | | | - Arnold J. Bendich
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (D.T.); (D.J.O.)
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12
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Manavella PA, Godoy Herz MA, Kornblihtt AR, Sorenson R, Sieburth LE, Nakaminami K, Seki M, Ding Y, Sun Q, Kang H, Ariel FD, Crespi M, Giudicatti AJ, Cai Q, Jin H, Feng X, Qi Y, Pikaard CS. Beyond transcription: compelling open questions in plant RNA biology. THE PLANT CELL 2023; 35:1626-1653. [PMID: 36477566 PMCID: PMC10226580 DOI: 10.1093/plcell/koac346] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/14/2022] [Accepted: 12/06/2022] [Indexed: 05/30/2023]
Abstract
The study of RNAs has become one of the most influential research fields in contemporary biology and biomedicine. In the last few years, new sequencing technologies have produced an explosion of new and exciting discoveries in the field but have also given rise to many open questions. Defining these questions, together with old, long-standing gaps in our knowledge, is the spirit of this article. The breadth of topics within RNA biology research is vast, and every aspect of the biology of these molecules contains countless exciting open questions. Here, we asked 12 groups to discuss their most compelling question among some plant RNA biology topics. The following vignettes cover RNA alternative splicing; RNA dynamics; RNA translation; RNA structures; R-loops; epitranscriptomics; long non-coding RNAs; small RNA production and their functions in crops; small RNAs during gametogenesis and in cross-kingdom RNA interference; and RNA-directed DNA methylation. In each section, we will present the current state-of-the-art in plant RNA biology research before asking the questions that will surely motivate future discoveries in the field. We hope this article will spark a debate about the future perspective on RNA biology and provoke novel reflections in the reader.
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Affiliation(s)
- Pablo A Manavella
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe 3000, Argentina
| | - Micaela A Godoy Herz
- Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular and CONICET-UBA, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Universidad de Buenos Aires (UBA), Buenos Aires C1428EHA, Argentina
| | - Alberto R Kornblihtt
- Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular and CONICET-UBA, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Universidad de Buenos Aires (UBA), Buenos Aires C1428EHA, Argentina
| | - Reed Sorenson
- School of Biological Sciences, University of UtahSalt Lake City 84112, USA
| | - Leslie E Sieburth
- School of Biological Sciences, University of UtahSalt Lake City 84112, USA
| | - Kentaro Nakaminami
- Center for Sustainable Resource Science, RIKEN, Kanagawa 230-0045, Japan
| | - Motoaki Seki
- Center for Sustainable Resource Science, RIKEN, Kanagawa 230-0045, Japan
- Cluster for Pioneering Research, RIKEN, Saitama 351-0198, Japan
- Kihara Institute for Biological Research, Yokohama City University, Kanagawa 244-0813, Japan
| | - Yiliang Ding
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Hunseung Kang
- Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Korea
| | - Federico D Ariel
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe 3000, Argentina
| | - Martin Crespi
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Evry, Université Paris-Saclay, Bâtiment 630, Orsay 91405, France
- Institute of Plant Sciences Paris-Saclay IPS2, Université de Paris, Bâtiment 630, Orsay 91405, France
| | - Axel J Giudicatti
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe 3000, Argentina
| | - Qiang Cai
- State Key Laboratory of Hybrid Rice, College of Life Science, Wuhan University, Wuhan 430072, China
| | - Hailing Jin
- Department of Microbiology and Plant Pathology and Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California 92507, USA
| | - Xiaoqi Feng
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Yijun Qi
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Craig S Pikaard
- Howard Hughes Medical Institute, Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA
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13
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State of the Art of the Molecular Biology of the Interaction between Cocoa and Witches’ Broom Disease: A Systematic Review. Int J Mol Sci 2023; 24:ijms24065684. [PMID: 36982760 PMCID: PMC10057015 DOI: 10.3390/ijms24065684] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/02/2022] [Accepted: 12/04/2022] [Indexed: 03/19/2023] Open
Abstract
Significant scientific advances to elucidate the Moniliophthora perniciosa pathosystem have been achieved in recent years, but the molecular biology of this pathogen-host interaction is still a field with many unanswered questions. In order to present insights at the molecular level, we present the first systematic review on the theme. All told, 1118 studies were extracted from public databases. Of these, 109 were eligible for the review, based on the inclusion and exclusion criteria. The results indicated that understanding the transition from the biotrophic-necrotrophic phase of the fungus is crucial for control of the disease. Proteins with strong biotechnological potential or that can be targets for pathosystem intervention were identified, but studies regarding possible applications are still limited. The studies identified revealed important genes in the M. perniciosa-host interaction and efficient molecular markers in the search for genetic variability and sources of resistance, with Theobroma cacao being the most common host. An arsenal of effectors already identified and not explored in the pathosystem were highlighted. This systematic review contributes to the understanding of the pathosystem at the molecular level, offering new insights and proposing different paths for the development of new strategies to control witches’ broom disease.
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14
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Volná A, Bartas M, Nezval J, Pech R, Pečinka P, Špunda V, Červeň J. Beyond the Primary Structure of Nucleic Acids: Potential Roles of Epigenetics and Noncanonical Structures in the Regulations of Plant Growth and Stress Responses. Methods Mol Biol 2023; 2642:331-361. [PMID: 36944887 DOI: 10.1007/978-1-0716-3044-0_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Epigenetics deals with changes in gene expression that are not caused by modifications in the primary sequence of nucleic acids. These changes beyond primary structures of nucleic acids not only include DNA/RNA methylation, but also other reversible conversions, together with histone modifications or RNA interference. In addition, under particular conditions (such as specific ion concentrations or protein-induced stabilization), the right-handed double-stranded DNA helix (B-DNA) can form noncanonical structures commonly described as "non-B DNA" structures. These structures comprise, for example, cruciforms, i-motifs, triplexes, and G-quadruplexes. Their formation often leads to significant differences in replication and transcription rates. Noncanonical RNA structures have also been documented to play important roles in translation regulation and the biology of noncoding RNAs. In human and animal studies, the frequency and dynamics of noncanonical DNA and RNA structures are intensively investigated, especially in the field of cancer research and neurodegenerative diseases. In contrast, noncanonical DNA and RNA structures in plants have been on the fringes of interest for a long time and only a few studies deal with their formation, regulation, and physiological importance for plant stress responses. Herein, we present a review focused on the main fields of epigenetics in plants and their possible roles in stress responses and signaling, with special attention dedicated to noncanonical DNA and RNA structures.
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Affiliation(s)
- Adriana Volná
- Department of Physics, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Martin Bartas
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Jakub Nezval
- Department of Physics, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Radomír Pech
- Department of Physics, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Petr Pečinka
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Vladimír Špunda
- Department of Physics, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
- Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic
| | - Jiří Červeň
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic.
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15
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Zhou J, Zhang W, Sun Q. R-loop: The new genome regulatory element in plants. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2022; 64:2275-2289. [PMID: 36223078 DOI: 10.1111/jipb.13383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
An R-loop is a three-stranded chromatin structure that consists of a displaced single strand of DNA and an RNA:DNA hybrid duplex, which was thought to be a rare by-product of transcription. However, recent genome-wide data have shown that R-loops are widespread and pervasive in a variety of genomes, and a growing body of experimental evidence indicates that R-loops have both beneficial and harmful effects on an organism. To maximize benefit and avoid harm, organisms have evolved several means by which they tightly regulate R-loop levels. Here, we summarize our current understanding of the biogenesis and effects of R-loops, the mechanisms that regulate them, and methods of R-loop profiling, reviewing recent research advances on R-loops in plants. Furthermore, we provide perspectives on future research directions for R-loop biology in plants, which might lead to a more comprehensive understanding of R-loop functions in plant genome regulation and contribute to future agricultural improvements.
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Affiliation(s)
- Jincong Zhou
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Weifeng Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
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16
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Gonzalo L, Tossolini I, Gulanicz T, Cambiagno DA, Kasprowicz-Maluski A, Smolinski DJ, Mammarella MF, Ariel FD, Marquardt S, Szweykowska-Kulinska Z, Jarmolowski A, Manavella PA. R-loops at microRNA encoding loci promote co-transcriptional processing of pri-miRNAs in plants. NATURE PLANTS 2022; 8:402-418. [PMID: 35449404 PMCID: PMC9023350 DOI: 10.1038/s41477-022-01125-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 03/08/2022] [Indexed: 05/03/2023]
Abstract
In most organisms, the maturation of nascent RNAs is coupled to transcription. Unlike in animals, the RNA polymerase II (RNAPII) transcribes microRNA genes (MIRNAs) as long and structurally variable pri-miRNAs in plants. Current evidence suggests that the miRNA biogenesis complex assembly initiates early during the transcription of pri-miRNAs in plants. However, it is unknown whether miRNA processing occurs co-transcriptionally. Here, we used native elongating transcript sequencing data and imaging techniques to demonstrate that plant miRNA biogenesis occurs coupled to transcription. We found that the entire biogenesis occurs co-transcriptionally for pri-miRNAs processed from the loop of the hairpin but requires a second nucleoplasmic step for those processed from the base. Furthermore, we found that co- and post-transcriptional miRNA processing mechanisms co-exist for most miRNAs in a dynamic balance. Notably, we discovered that R-loops, formed near the transcription start site region of MIRNAs, promote co-transcriptional pri-miRNA processing. Furthermore, our results suggest the neofunctionalization of co-transcriptionally processed miRNAs, boosting countless regulatory scenarios.
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Affiliation(s)
- Lucia Gonzalo
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - Ileana Tossolini
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - Tomasz Gulanicz
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Torun, Poland
| | - Damian A Cambiagno
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
- Unidad de Estudios Agropecuarios (UDEA), INTA-CONICET, Córdoba, Argentina
| | - Anna Kasprowicz-Maluski
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland
| | - Dariusz Jan Smolinski
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Torun, Poland
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Torun, Poland
| | - María Florencia Mammarella
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - Federico D Ariel
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
| | - Sebastian Marquardt
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Zofia Szweykowska-Kulinska
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland
| | - Artur Jarmolowski
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland.
| | - Pablo A Manavella
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina.
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17
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Wang W, Cheng L, Sun Q. Chromatin Immunoprecipitation in Chloroplasts. Curr Protoc 2022; 2:e360. [PMID: 35077029 DOI: 10.1002/cpz1.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chromatin is the genetic material assembled by nucleic acids (including DNA and RNA) and proteins. The biological functions of chromatin are highly dependent on the interaction between DNA (and/or RNA) and proteins that bind to it. Chromatin immunoprecipitation (ChIP) is a powerful technique for evaluating these interactions and has been widely used to characterize the functions of nuclear proteins. However, its application in identifying plant organellar chromatin-binding proteins is lagging. This article describes the method for analyzing the association of chloroplast-localized proteins with the chloroplast genome. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Chloroplast isolation Basic Protocol 2: Crosslinking of DNA-Protein complexes Basic Protocol 3: Chromatin isolation and preparation Support Protocol: Bead-antibody complex preparation Basic Protocol 4: Immunoprecipitation and washes Basic Protocol 5: DNA preparation Basic Protocol 6: Analysis of results.
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Affiliation(s)
- Wenjie Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Lingling Cheng
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
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18
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Chen S, Dong X, Yang Z, Hou X, Liu L. Regulation of the Development in Physcomitrium (Physcomitrella) patens implicates the functional differentiation of plant RNase H1s. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 313:111070. [PMID: 34763863 DOI: 10.1016/j.plantsci.2021.111070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/14/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
R-loops, consisting of a DNA:RNA hybrid and a single-stranded DNA (ssDNA), form naturally as functional chromosome structures and are crucial in many vital biological processes. However, disrupted R-loop homeostasis will threat to the integrity and stability of genome. As the endonuclease, RNase H1 can efficiently recognize and remove excess R-loops to protect organisms from DNA damage induced by R-loop over-accumulation. Here, we investigated the function of RNase H1 in Physcomitrium (Physcomitrella) patens to illustrate its important role in the evolution of plants. We found that PpRNH1A dysfunction seriously affected shoot growth and branch formation in P. patens, revealing a noticeable functional difference between PpRNH1A and AtRNH1A of Arabidopsis. Furthermore, auxin signaling was significantly affected at the transcriptional level in PpRNH1A mutant plants, as a result of the accumulation of R-loops at several auxin-related genes. This study provides evidence that PpRNH1A regulates the development of P. patens by controlling R-loop formation at specific loci to modulate the transcription of auxin-related genes. It also highlights the interspecific functional differences between early land plants and vascular plants, despite crucial and conserved role of RNase H1 played in maintaining R-loop homeostasis.
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Affiliation(s)
- Silin Chen
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiumei Dong
- Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, China
| | - Zhuo Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Xin Hou
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Li Liu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, China.
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19
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Liu K, Sun Q. Intragenic tRNA-promoted R-loops orchestrate transcription interference for plant oxidative stress responses. THE PLANT CELL 2021; 33:3574-3591. [PMID: 34463741 PMCID: PMC8566210 DOI: 10.1093/plcell/koab220] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 08/26/2021] [Indexed: 05/15/2023]
Abstract
Eukaryotic genomes are transcribed by at least three RNA polymerases, RNAPI, II, and III. Co-transcriptional R-loops play diverse roles in genome regulation and maintenance. However, little is known about how R-loops regulate transcription interference, the transcriptional event that is caused by different RNA polymerases transcribing the same genomic templates. Here, we established that the intragenic transfer RNA (tRNA) genes can promote sense R-loop enrichment (named intra-tR-loops) in Arabidopsis thaliana, and found that intra-tR-loops are decreased in an RNAPIII mutant, NUCLEAR RNA POLYMERASE C, SUBUNIT 7(nrpc7-1). NRPC7 is co-localized with RNAPIIS2P at intragenic tRNA genes and interferes with RNAPIIS2P elongation. Conversely, the binding of NRPC7 at intragenic tRNA genes is increased following inhibition of RNAPII elongation. The transcription of specific tRNA host genes is inhibited by RNAPIII, and the inhibition of tRNA host genes is intra-tR-loop dependent. Moreover, alleviating the inhibition of tRNAPro-induced intra-tR-loops on its host gene AtNUDX1 promotes oxidative stress tolerance in A. thaliana. Our work suggests intra-tR-loops regulate host gene expression by modulating RNA polymerases interference.
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Affiliation(s)
- Kunpeng Liu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
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20
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Gao J, Zhang P, Li X, Wu W, Wei H, Zhang W. Toward an understanding of the detection and function of R-loops in plants. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:6110-6122. [PMID: 34115858 DOI: 10.1093/jxb/erab280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 06/10/2021] [Indexed: 06/12/2023]
Abstract
Although lagging behind studies in humans and other mammals, studies of R-loops in plants have recently entered an exciting stage in which the roles of R-loops in gene expression, genome stability, epigenomic signatures, and plant development and stress responses are being elucidated. Here, we review the strengths and weaknesses of existing methodologies, which were largely developed for R-loop studies in mammals, and then discuss the potential challenges of applying these methodologies to R-loop studies in plants. We then focus on recent advances in the functional characterization of R-loops in Arabidopsis thaliana and rice. Recent studies in plants indicate that there are coordinated relationships between R-loops and gene expression, and between R-loops and epigenomic signatures that depend, in part, on the types of R-loops involved. Finally, we discuss the emerging roles of R-loops in plants and directions for future research.
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Affiliation(s)
- Jingjing Gao
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Pengyue Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Xinxu Li
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Wenqi Wu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China
| | - Hairong Wei
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
| | - Wenli Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, JCIC-MCP, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
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21
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Cheng L, Wang W, Yao Y, Sun Q. Mitochondrial RNase H1 activity regulates R-loop homeostasis to maintain genome integrity and enable early embryogenesis in Arabidopsis. PLoS Biol 2021; 19:e3001357. [PMID: 34343166 PMCID: PMC8330923 DOI: 10.1371/journal.pbio.3001357] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 07/08/2021] [Indexed: 11/24/2022] Open
Abstract
Plant mitochondrial genomes undergo frequent homologous recombination (HR). Ectopic HR activity is inhibited by the HR surveillance pathway, but the underlying regulatory mechanism is unclear. Here, we show that the mitochondrial RNase H1 AtRNH1B impairs the formation of RNA:DNA hybrids (R-loops) and participates in the HR surveillance pathway in Arabidopsis thaliana. AtRNH1B suppresses ectopic HR at intermediate-sized repeats (IRs) and thus maintains mitochondrial DNA (mtDNA) replication. The RNase H1 AtRNH1C is restricted to the chloroplast; however, when cells lack AtRNH1B, transport of chloroplast AtRNH1C into the mitochondria secures HR surveillance, thus ensuring the integrity of the mitochondrial genome and allowing embryogenesis to proceed. HR surveillance is further regulated by the single-stranded DNA-binding protein ORGANELLAR SINGLE-STRANDED DNA BINDING PROTEIN1 (OSB1), which decreases the formation of R-loops. This study uncovers a facultative dual targeting mechanism between organelles and sheds light on the roles of RNase H1 in organellar genome maintenance and embryogenesis. This study clarifies the function of mitochondrial RNase H1 in genome stability and early embryogenesis in plants, and shows that mitochondrial R-loops are involved in homologous recombination surveillance of mtDNA. Facultative re-targeting of the chloroplast RNase H1 protein to mitochondria, in response to cellular conditions, can help guarantee mitochondrial RNase H1 activity.
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Affiliation(s)
- Lingling Cheng
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Wenjie Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Yao Yao
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.,Tsinghua-Peking Center for Life Sciences, Beijing, China
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22
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Wang W, Li K, Yang Z, Hou Q, Zhao WW, Sun Q. RNase H1C collaborates with ssDNA binding proteins WHY1/3 and recombinase RecA1 to fulfill the DNA damage repair in Arabidopsis chloroplasts. Nucleic Acids Res 2021; 49:6771-6787. [PMID: 34133716 PMCID: PMC8266629 DOI: 10.1093/nar/gkab479] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/25/2021] [Accepted: 05/19/2021] [Indexed: 12/28/2022] Open
Abstract
Proper repair of damaged DNA is crucial for genetic integrity and organismal survival. As semi-autonomous organelles, plastids have their own genomes whose integrity must be preserved. Several factors have been shown to participate in plastid DNA damage repair; however, the underlying mechanism remains unclear. Here, we elucidate a mechanism of homologous recombination (HR) repair in chloroplasts that involves R-loops. We find that the recombinase RecA1 forms filaments in chloroplasts during HR repair, but aggregates as puncta when RNA:DNA hybrids accumulate. ssDNA-binding proteins WHY1/3 and chloroplast RNase H1 AtRNH1C are recruited to the same genomic sites to promote HR repair. Depletion of AtRNH1C or WHY1/3 significantly suppresses the binding of RNA polymerase to the damaged DNA, thus reducing HR repair and modulating microhomology-mediated double-strand break repair. Furthermore, we show that DNA polymerase IB works with AtRNH1C genetically to complete the DNA damage repair process. This study reveals the positive role of R-loops in facilitating the activities of WHY1/3 and RecA1, which in turn secures HR repair and organellar development.
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Affiliation(s)
- Wenjie Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Kuan Li
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Zhuo Yang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Quancan Hou
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Wei W Zhao
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Qianwen Sun
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
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23
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Wang B, Artsimovitch I. NusG, an Ancient Yet Rapidly Evolving Transcription Factor. Front Microbiol 2021; 11:619618. [PMID: 33488562 PMCID: PMC7819879 DOI: 10.3389/fmicb.2020.619618] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 12/07/2020] [Indexed: 12/19/2022] Open
Abstract
Timely and accurate RNA synthesis depends on accessory proteins that instruct RNA polymerase (RNAP) where and when to start and stop transcription. Among thousands of transcription factors, NusG/Spt5 stand out as the only universally conserved family of regulators. These proteins interact with RNAP to promote uninterrupted RNA synthesis and with diverse cellular partners to couple transcription to RNA processing, modification or translation, or to trigger premature termination of aberrant transcription. NusG homologs are present in all cells that utilize bacterial-type RNAP, from endosymbionts to plants, underscoring their ancient and essential function. Yet, in stark contrast to other core RNAP components, NusG family is actively evolving: horizontal gene transfer and sub-functionalization drive emergence of NusG paralogs, such as bacterial LoaP, RfaH, and UpxY. These specialized regulators activate a few (or just one) operons required for expression of antibiotics, capsules, secretion systems, toxins, and other niche-specific macromolecules. Despite their common origin and binding site on the RNAP, NusG homologs differ in their target selection, interacting partners and effects on RNA synthesis. Even among housekeeping NusGs from diverse bacteria, some factors promote pause-free transcription while others slow the RNAP down. Here, we discuss structure, function, and evolution of NusG proteins, focusing on unique mechanisms that determine their effects on gene expression and enable bacterial adaptation to diverse ecological niches.
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Affiliation(s)
- Bing Wang
- Department of Microbiology and the Center for RNA Biology, The Ohio State University, Columbus, OH, United States
| | - Irina Artsimovitch
- Department of Microbiology and the Center for RNA Biology, The Ohio State University, Columbus, OH, United States
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24
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Wang B, Gumerov VM, Andrianova EP, Zhulin IB, Artsimovitch I. Origins and Molecular Evolution of the NusG Paralog RfaH. mBio 2020; 11:e02717-20. [PMID: 33109766 PMCID: PMC7593976 DOI: 10.1128/mbio.02717-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/01/2020] [Indexed: 01/04/2023] Open
Abstract
The only universally conserved family of transcription factors comprises housekeeping regulators and their specialized paralogs, represented by well-studied NusG and RfaH. Despite their ubiquity, little information is available on the evolutionary origins, functions, and gene targets of the NusG family members. We built a hidden Markov model profile of RfaH and identified its homologs in sequenced genomes. While NusG is widespread among bacterial phyla and coresides with genes encoding RNA polymerase and ribosome in all except extremely reduced genomes, RfaH is mostly limited to Proteobacteria and lacks common gene neighbors. RfaH activates only a few xenogeneic operons that are otherwise silenced by NusG and Rho. Phylogenetic reconstructions reveal extensive duplications and horizontal transfer of rfaH genes, including those borne by plasmids, and the molecular evolution pathway of RfaH, from "early" exclusion of the Rho terminator and tightened RNA polymerase binding to "late" interactions with the ops DNA element and autoinhibition, which together define the RfaH regulon. Remarkably, NusG is not only ubiquitous in Bacteria but also common in plants, where it likely modulates the transcription of plastid genes.IMPORTANCE In all domains of life, NusG-like proteins make contacts similar to those of RNA polymerase and promote pause-free transcription yet may play different roles, defined by their divergent interactions with nucleic acids and accessory proteins, in the same cell. This duality is illustrated by Escherichia coli NusG and RfaH, which silence and activate xenogenes, respectively. We combined sequence analysis and recent functional and structural insights to envision the evolutionary transformation of NusG, a core regulator that we show is present in all cells using bacterial RNA polymerase, into a virulence factor, RfaH. Our results suggest a stepwise conversion of a NusG duplicate copy into a sequence-specific regulator which excludes NusG from its targets but does not compromise the regulation of housekeeping genes. We find that gene duplication and lateral transfer give rise to a surprising diversity within the only ubiquitous family of transcription factors.
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Affiliation(s)
- Bing Wang
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
- The Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
| | - Vadim M Gumerov
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
- Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio, USA
| | | | - Igor B Zhulin
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
- Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio, USA
| | - Irina Artsimovitch
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
- The Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
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25
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Leister D, Kleine T. Extending the Repertoire of mTERF Proteins with Functions in Organellar Gene Expression. MOLECULAR PLANT 2020; 13:817-819. [PMID: 32298787 DOI: 10.1016/j.molp.2020.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/08/2020] [Accepted: 04/09/2020] [Indexed: 05/16/2023]
Affiliation(s)
- Dario Leister
- Plant Molecular Biology (Botany), Department of Biology I, Ludwig-Maximilians-University München, 82152 Martinsried, Germany
| | - Tatjana Kleine
- Plant Molecular Biology (Botany), Department of Biology I, Ludwig-Maximilians-University München, 82152 Martinsried, Germany.
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26
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Plant Ribonuclease J: An Essential Player in Maintaining Chloroplast RNA Quality Control for Gene Expression. PLANTS 2020; 9:plants9030334. [PMID: 32151111 PMCID: PMC7154860 DOI: 10.3390/plants9030334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 12/27/2022]
Abstract
RNA quality control is an indispensable but poorly understood process that enables organisms to distinguish functional RNAs from nonfunctional or inhibitory ones. In chloroplasts, whose gene expression activities are required for photosynthesis, retrograde signaling, and plant development, RNA quality control is of paramount importance, as transcription is relatively unregulated. The functional RNA population is distilled from this initial transcriptome by a combination of RNA-binding proteins and ribonucleases. One of the key enzymes is RNase J, a 5′→3′ exoribonuclease and an endoribonuclease that has been shown to trim 5′ RNA termini and eliminate deleterious antisense RNA. In the absence of RNase J, embryo development cannot be completed. Land plant RNase J contains a highly conserved C-terminal domain that is found in GT-1 DNA-binding transcription factors and is not present in its bacterial, archaeal, and algal counterparts. The GT-1 domain may confer specificity through DNA and/or RNA binding and/or protein–protein interactions and thus be an element in the mechanisms that identify target transcripts among diverse RNA populations. Further understanding of chloroplast RNA quality control relies on discovering how RNase J is regulated and how its specificity is imparted.
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