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1
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Martinho C. From RdDM to plant defence. NATURE PLANTS 2024; 10:1442-1443. [PMID: 39349616 DOI: 10.1038/s41477-024-01806-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2024]
Affiliation(s)
- Claudia Martinho
- School of Life Sciences, Division of Plant Sciences, University of Dundee, James Hutton Institute, Dundee, UK.
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2
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Nakashima K, Yuhazu M, Mikuriya S, Kasai M, Abe J, Taneda A, Kanazawa A. Frequency of cytosine methylation in the adjacent regions of soybean retrotransposon SORE-1 depends on chromosomal location. Genome 2024; 67:1-12. [PMID: 37746933 DOI: 10.1139/gen-2023-0044] [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: 09/26/2023]
Abstract
Mobilization of transposable elements (TEs) is suppressed by epigenetic mechanisms involving cytosine methylation. However, few studies have focused on clarifying relationships between epigenetic influences of TEs on the adjacent DNA regions and time after insertion of TEs into the genome and/or their chromosomal location. Here we addressed these issues using soybean retrotransposon SORE-1. We analyzed SORE-1, inserted in exon 1 of the GmphyA2 gene, one of the newest insertions in this family so far identified. Cytosine methylation was detected in this element but was barely present in the adjacent regions. These results were correlated, respectively, with the presence and absence of the production of short interfering RNAs. Cytosine methylation profiles of 74 SORE-1 elements in the Williams 82 reference genome indicated that methylation frequency in the adjacent regions of SORE-1 was profoundly higher in pericentromeric regions than in euchromatic chromosome arms and was only weakly correlated with the length of time after insertion into the genome. Notably, the higher level of methylation in the 5' adjacent regions of SORE-1 coincided with the presence of repetitive elements in pericentromeric regions. Together, these results suggest that epigenetic influence of SORE-1 on the adjacent regions is influenced by its location on the chromosome.
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Affiliation(s)
- Kenta Nakashima
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Mashiro Yuhazu
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Shun Mikuriya
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Megumi Kasai
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Jun Abe
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Akito Taneda
- Graduate School of Science and Technology, Hirosaki University, Hirosaki, Aomori 036-8561, Japan
| | - Akira Kanazawa
- Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
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3
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Tang X, Li Q, Feng X, Yang B, Zhong X, Zhou Y, Wang Q, Mao Y, Xie W, Liu T, Tang Q, Guo W, Wu F, Feng X, Wang Q, Lu Y, Xu J. Identification and Functional Analysis of Drought-Responsive Long Noncoding RNAs in Maize Roots. Int J Mol Sci 2023; 24:15039. [PMID: 37894720 PMCID: PMC10606207 DOI: 10.3390/ijms242015039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 10/29/2023] Open
Abstract
Long noncoding RNAs (lncRNAs) are transcripts with lengths of more than 200 nt and limited protein-coding potential. They were found to play important roles in plant stress responses. In this study, the maize drought-tolerant inbred line AC7643 and drought-sensitive inbred line AC7729/TZSRW, as well as their recombinant inbred lines (RILs) were selected to identify drought-responsive lncRNAs in roots. Compared with non-responsive lncRNAs, drought-responsive lncRNAs had different sequence characteristics in length of genes and number of exons. The ratio of down-regulated lncRNAs induced by drought was significantly higher than that of coding genes; and lncRNAs were more widespread expressed in recombination sites in the RILs. Additionally, by integration of the modifications of DNA 5-methylcytidine (5mC), histones, and RNA N6-methyladenosine (m6A), it was found that the enrichment of histone modifications associated with transcriptional activation in the genes generated lncRNAs was lower that coding genes. The lncRNAs-mRNAs co-expression network, containing 15,340 coding genes and 953 lncRNAs, was constructed to investigate the molecular functions of lncRNAs. There are 13 modules found to be associated with survival rate under drought. We found nine SNPs located in lncRNAs among the modules associated with plant survival under drought. In conclusion, we revealed the characteristics of lncRNAs responding to drought in maize roots based on multiomics studies. These findings enrich our understanding of lncRNAs under drought and shed light on the complex regulatory networks that are orchestrated by the noncoding RNAs in response to drought stress.
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Affiliation(s)
- Xin Tang
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Qimeng Li
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiaoju Feng
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Bo Yang
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiu Zhong
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yang Zhou
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Qi Wang
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yan Mao
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Wubin Xie
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Tianhong Liu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Qi Tang
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Wei Guo
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Fengkai Wu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xuanjun Feng
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Qingjun Wang
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yanli Lu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Jie Xu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China; (X.T.); (Q.L.); (X.F.); (B.Y.); (X.Z.); (Y.Z.); (Q.W.); (Y.M.); (W.X.); (T.L.); (Q.T.); (W.G.); (F.W.); (X.F.); (Q.W.)
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
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4
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Yang DL, Huang K, Deng D, Zeng Y, Wang Z, Zhang Y. DNA-dependent RNA polymerases in plants. THE PLANT CELL 2023; 35:3641-3661. [PMID: 37453082 PMCID: PMC10533338 DOI: 10.1093/plcell/koad195] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 06/09/2023] [Accepted: 05/29/2023] [Indexed: 07/18/2023]
Abstract
DNA-dependent RNA polymerases (Pols) transfer the genetic information stored in genomic DNA to RNA in all organisms. In eukaryotes, the typical products of nuclear Pol I, Pol II, and Pol III are ribosomal RNAs, mRNAs, and transfer RNAs, respectively. Intriguingly, plants possess two additional Pols, Pol IV and Pol V, which produce small RNAs and long noncoding RNAs, respectively, mainly for silencing transposable elements. The five plant Pols share some subunits, but their distinct functions stem from unique subunits that interact with specific regulatory factors in their transcription cycles. Here, we summarize recent advances in our understanding of plant nucleus-localized Pols, including their evolution, function, structures, and transcription cycles.
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Affiliation(s)
- Dong-Lei Yang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Nanjing Agricultural University, Nanjing 210095, China
| | - Kun Huang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Deyin Deng
- State Key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang Agriculture and Forestry University, Lin’an, Hangzhou 311300, China
| | - Yuan Zeng
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Zhenxing Wang
- College of Horticulture, National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Nanjing Agricultural University, Nanjing 210095, China
| | - Yu Zhang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
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5
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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: 3.5] [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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6
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Wang F, Huang HY, Huang J, Singh J, Pikaard CS. Enzymatic reactions of AGO4 in RNA-directed DNA methylation: siRNA duplex loading, passenger strand elimination, target RNA slicing, and sliced target retention. Genes Dev 2023; 37:103-118. [PMID: 36746605 PMCID: PMC10069450 DOI: 10.1101/gad.350240.122] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 01/13/2023] [Indexed: 02/08/2023]
Abstract
RNA-directed DNA methylation in plants is guided by 24-nt siRNAs generated in parallel with 23-nt RNAs of unknown function. We show that 23-nt RNAs function as passenger strands during 24-nt siRNA incorporation into AGO4. The 23-nt RNAs are then sliced into 11- and 12-nt fragments, with 12-nt fragments remaining associated with AGO4. Slicing recapitulated with recombinant AGO4 and synthetic RNAs reveals that siRNAs of 21-24 nt, with any 5'-terminal nucleotide, can guide slicing, with sliced RNAs then retained by AGO4. In vivo, RdDM target locus RNAs that copurify with AGO4 also display a sequence signature of slicing. Comparing plants expressing slicing-competent versus slicing-defective AGO4 shows that slicing elevates cytosine methylation levels at virtually all RdDM loci. We propose that siRNA passenger strand elimination and AGO4 tethering to sliced target RNAs are distinct modes by which AGO4 slicing enhances RNA-directed DNA methylation.
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Affiliation(s)
- Feng Wang
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA
- Howard Hughes Medical Institute, Indiana University, Bloomington, Indiana 47405, USA
| | - Hsiao-Yun Huang
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA
| | - Jie Huang
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA
| | - Jasleen Singh
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA
| | - Craig S Pikaard
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA;
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA
- Howard Hughes Medical Institute, Indiana University, Bloomington, Indiana 47405, USA
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7
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Li T, Zhang R, Satheesh V, Wang P, Ma G, Guo J, An GY, Lei M. The chromatin remodeler BRAHMA recruits HISTONE DEACETYLASE6 to regulate root growth inhibition in response to phosphate starvation in Arabidopsis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2022; 64:2314-2326. [PMID: 35972795 DOI: 10.1111/jipb.13345] [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: 05/25/2022] [Accepted: 08/14/2022] [Indexed: 06/15/2023]
Abstract
Plasticity in root system architecture (RSA) allows plants to adapt to changing nutritional status in the soil. Phosphorus availability is a major determinant of crop yield, and RSA remodeling is critical to increasing the efficiency of phosphorus acquisition. Although substantial progress has been made in understanding the signaling mechanism driving phosphate starvation responses in plants, whether and how epigenetic regulatory mechanisms contribute is poorly understood. Here, we report that the Switch defective/sucrose non-fermentable (SWI/SNF) ATPase BRAHMA (BRM) is involved in the local response to phosphate (Pi) starvation. The loss of BRM function induces iron (Fe) accumulation through increased LOW PHOSPHATE ROOT1 (LPR1) and LPR2 expression, reducing primary root length under Pi deficiency. We also demonstrate that BRM recruits the histone deacetylase (HDA) complex HDA6-HDC1 to facilitate histone H3 deacetylation at LPR loci, thereby negatively regulating local Pi deficiency responses. BRM is degraded under Pi deficiency conditions through the 26 S proteasome pathway, leading to increased histone H3 acetylation at the LPR loci. Collectively, our data suggest that the chromatin remodeler BRM, in concert with HDA6, negatively regulates Fe-dependent local Pi starvation responses by transcriptionally repressing the RSA-related genes LPR1 and LPR2 in Arabidopsis thaliana.
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Affiliation(s)
- Tao Li
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ruyue Zhang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Viswanathan Satheesh
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Peng Wang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Guojie Ma
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Jianfei Guo
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - Guo-Yong An
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Mingguang Lei
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
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8
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Jagić M, Vuk T, Škiljaica A, Markulin L, Vičić Bočkor V, Tokić M, Miškec K, Razdorov G, Habazin S, Šoštar M, Weber I, Bauer N, Leljak Levanić D. BPM1 regulates RdDM-mediated DNA methylation via a cullin 3 independent mechanism. PLANT CELL REPORTS 2022; 41:2139-2157. [PMID: 36066603 DOI: 10.1007/s00299-022-02911-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
BPM1 interacts with components of the DDR complex and stimulates DNA methylation at CHH sites, suggesting its involvement in the RdDM methylation pathway. The best-known function of MATH-BTB proteins, including Arabidopsis BPM proteins, is their role as substrate-specific adaptors of CUL3-based E3 ligases in the ubiquitin-proteasome pathway. This paper reports a new CUL3-independent role of BPM1 in RNA-directed DNA methylation (RdDM). Using quantitative and qualitative Y2H, pull down, microscale thermophoresis and FRET-FLIM, we demonstrate that BPM1 interacts with DMS3 and RDM1, components of the chromatin remodeling DDR complex involved in the recruitment of the RdDM methylation machinery. All three proteins colocalized predominantly in the nucleus. The MATH domain, which specifically binds proteins destined for degradation, was not essential for interactions with DMS3 and RDM1. In plants overexpressing BPM1, endogenous DMS3 protein levels were stable, indicating that BPM1 does not induce proteasomal degradation. In RDM1-overexpressing plants, RDM1 was not ubiquitinated. Together, these results suggest that BPM1 does not mediate the degradation of DMS3 and RDM1. Additionally, overexpression of BPM1 caused increased global methylation levels as well as CHH methylation in promoters of two RdDM-regulated genes, FWA and CML41. Overall, BPM1 seems to have a stimulating effect on RdDM activity, and this role appears to be unrelated to its known function as a Cul3-based E3 ligase adaptor.
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Affiliation(s)
- Mateja Jagić
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Tamara Vuk
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Andreja Škiljaica
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Lucija Markulin
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Vedrana Vičić Bočkor
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Mirta Tokić
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Karlo Miškec
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | | | | | - Marko Šoštar
- Division of Molecular Biology, Institute Ruđer Bošković, Zagreb, Croatia
| | - Igor Weber
- Division of Molecular Biology, Institute Ruđer Bošković, Zagreb, Croatia
| | - Nataša Bauer
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Dunja Leljak Levanić
- Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia.
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9
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Hou Q, Zhang T, Qi Y, Dong Z, Wan X. Epigenetic Dynamics and Regulation of Plant Male Reproduction. Int J Mol Sci 2022; 23:ijms231810420. [PMID: 36142333 PMCID: PMC9499625 DOI: 10.3390/ijms231810420] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 08/30/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
Flowering plant male germlines develop within anthers and undergo epigenetic reprogramming with dynamic changes in DNA methylation, chromatin modifications, and small RNAs. Profiling the epigenetic status using different technologies has substantially accumulated information on specific types of cells at different stages of male reproduction. Many epigenetically related genes involved in plant gametophyte development have been identified, and the mutation of these genes often leads to male sterility. Here, we review the recent progress on dynamic epigenetic changes during pollen mother cell differentiation, microsporogenesis, microgametogenesis, and tapetal cell development. The reported epigenetic variations between male fertile and sterile lines are summarized. We also summarize the epigenetic regulation-associated male sterility genes and discuss how epigenetic mechanisms in plant male reproduction can be further revealed.
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10
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Miao W, Dai J, Wang Y, Wang Q, Lu C, La Y, Niu J, Tan F, Zhou S, Wu Y, Chen H, La H. Roles of IDM3 and SDJ1/2/3 in Establishment and/or Maintenance of DNA Methylation in Arabidopsis. PLANT & CELL PHYSIOLOGY 2021; 62:1409-1422. [PMID: 34185870 DOI: 10.1093/pcp/pcab091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
Previous studies had demonstrated that in Arabidopsis, IDM3 is involved in ROS1-mediated DNA demethylation pathway, and SUVH-SDJ complex functions as a DNA methylation reader complex for enhancing gene transcription, which presumably recruits ROS1 to the promoters of target genes for DNA demethylation. Here, our analyses, however, showed that the IDM3 and SDJ1/2/3, the components of the SUVH-SDJ complex, are implicated in establishing and/or maintaining DNA methylation as well through DDR (DRD1-DMS3-RDM1) complex. idm3-3 or sdj1/2/3 mutations led to genome-wide DNA hypomethylation, and both mutants shared a large number of common hypo-DMRs (Differentially Methylated Regions) with rdm1-4 and dms3-4, suggesting that IDM3 and SDJ1/2/3 help establish and/or maintain DNA methylation, mediated by RdDM pathway, at a subset of genomic regions largely through DDR complex. IDM3 is able to strongly interact with RDM1 and DMS3, but weakly with SDJ1 and SDJ3; SDJ1 and SDJ3 is capable of interacting separately with RDM1 and DMS3. Furthermore, comparisons of DNA methylation features in idm3-3 and sdj1/2/3 indicated that idm3-3 and sdj1/2/3 mutations make differential impacts on DNA methylation levels and patterns on a genome-wide scale, indicating that they are targeted to quite distinct genomic regions for aiding in DNA methylation. Further analyses on ChIP-seq data demonstrated that RDM1, DMS3 and NRPE1 are enriched in IDM3- and SDJ1/2/3-targted regions. Altogether, our results provide clear demonstration that IDM3 and SDJ1/2/3 play a part in establishing and/or maintaining DNA methylation of a group of genomic regions, through the DDR complex.
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Affiliation(s)
- Wei Miao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Jie Dai
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Yutong Wang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Qianqian Wang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Chong Lu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Yumei La
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Jiayu Niu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Feng Tan
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Shaoxia Zhou
- College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Yufeng Wu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Bioinformatics Center, Nanjing Agricultural University, Nanjing 210095, China
| | - Huhui Chen
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Honggui La
- College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
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11
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Huang P, Huang H, Lin X, Liu P, Zhao L, Nie W, Zhu J, Lang Z. MSI4/FVE is required for accumulation of 24-nt siRNAs and DNA methylation at a subset of target regions of RNA-directed DNA methylation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 108:347-357. [PMID: 34314526 PMCID: PMC9292519 DOI: 10.1111/tpj.15441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 07/20/2021] [Indexed: 05/20/2023]
Abstract
DNA methylation is an important epigenetic mark. In plants, de novo DNA methylation occurs mainly through the RNA-directed DNA methylation (RdDM) pathway. Researchers have previously inferred that a flowering regulator, MULTICOPY SUPPRESSOR OF IRA1 4 (MSI4)/FVE, is involved in non-CG methylation at several RdDM targets, suggesting a role of FVE in RdDM. However, whether and how FVE affects RdDM genome-wide is not known. Here, we report that FVE is required for DNA methylation at thousands of RdDM target regions. In addition, dysfunction of FVE significantly reduces 24-nucleotide siRNA accumulation that is dependent on factors downstream in the RdDM pathway. By using chromatin immunoprecipitation and sequencing (ChIP-seq), we show that FVE directly binds to FVE-dependent 24-nucleotide siRNA cluster regions. Our results also indicate that FVE may function in RdDM by physically interacting with RDM15, a downstream factor in the RdDM pathway. Our study has therefore revealed that FVE, by associating with RDM15, directly regulates DNA methylation and siRNA accumulation at a subset of RdDM targets.
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Affiliation(s)
- Pei Huang
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
- University of Chinese Academy of SciencesNo.19 Yuquan Road, Shijingshan DistrictBeijing100049China
| | - Huan Huang
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Xueqiang Lin
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Pan Liu
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Lun Zhao
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
- National Key Laboratory of Crop Genetic ImprovementNational Center of Rapeseed ImprovementHuazhong Agricultural UniversityWuhan430070China
| | - Wen‐Feng Nie
- Department of HorticultureCollege of Horticulture and Plant ProtectionYangzhou UniversityYangzhouJiangsu225009China
| | - Jian‐Kang Zhu
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
| | - Zhaobo Lang
- Shanghai Center for Plant Stress BiologyNational Key Laboratory of Plant Molecular GeneticsCenter for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai201602China
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12
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Rothi MH, Tsuzuki M, Sethuraman S, Wierzbicki AT. Reinforcement of transcriptional silencing by a positive feedback between DNA methylation and non-coding transcription. Nucleic Acids Res 2021; 49:9799-9808. [PMID: 34469565 PMCID: PMC8464056 DOI: 10.1093/nar/gkab746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 07/09/2021] [Accepted: 08/23/2021] [Indexed: 11/12/2022] Open
Abstract
Non-coding transcription is an important determinant of heterochromatin formation. In Arabidopsis thaliana a specialized RNA polymerase V (Pol V) transcribes pervasively and produces long non-coding RNAs. These transcripts work with small interfering RNA to facilitate locus-specific establishment of RNA-directed DNA methylation (RdDM). Subsequent maintenance of RdDM is associated with elevated levels of Pol V transcription. However, the impact of DNA methylation on Pol V transcription remained unresolved. We found that DNA methylation strongly enhances Pol V transcription. The level of Pol V transcription is reduced in mutants defective in RdDM components working downstream of Pol V, indicating that RdDM is maintained by a mutual reinforcement of DNA methylation and Pol V transcription. Pol V transcription is affected only on loci that lose DNA methylation in all sequence contexts in a particular mutant, including mutants lacking maintenance DNA methyltransferases, which suggests that RdDM works in a complex crosstalk with other silencing pathways.
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Affiliation(s)
- M Hafiz Rothi
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Masayuki Tsuzuki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.,Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan
| | - Shriya Sethuraman
- Bioinformatics Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Andrzej T Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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13
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Zhou JX, Du P, Liu ZW, Feng C, Cai XW, He XJ. FVE promotes RNA-directed DNA methylation by facilitating the association of RNA polymerase V with chromatin. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:467-479. [PMID: 33942410 DOI: 10.1111/tpj.15302] [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: 03/09/2021] [Revised: 04/19/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
Association of RNA polymerase V (Pol V) with chromatin is a critical step for RNA- directed DNA methylation (RdDM) in plants. Although the methylated DNA-binding proteins SUVH2 and SUVH9 and the chromatin remodeler-containing complex DRD1-DMS3-RDM1 are known to be required for the association of Pol V with chromatin, the molecular mechanisms underlying the association of Pol V with different chromatin environments remain largely unknown. Here we found that SUVH9 interacts with FVE, a homolog of the mammalian retinoblastoma-associated protein, which has been previously identified as a shared subunit of the histone deacetylase complex and the polycomb-type histone H3K27 trimethyltransferase complex. We demonstrated that FVE facilitates the association of Pol V with chromatin and thus contributes to DNA methylation at a substantial subset of RdDM target loci. Compared with FVE-independent RdDM target loci, FVE-dependent RdDM target loci are more abundant in gene-rich chromosome arms than in pericentromeric heterochromatin regions. This study contributes to our understanding of how the association of Pol V with chromatin is regulated in different chromatin environments.
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Affiliation(s)
- Jin-Xing Zhou
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Ping Du
- National Institute of Biological Sciences, Beijing, 102206, China
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Zhang-Wei Liu
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Chao Feng
- National Institute of Biological Sciences, Beijing, 102206, China
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Xue-Wei Cai
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Xin-Jian He
- National Institute of Biological Sciences, Beijing, 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, 100084, China
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14
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Abstract
Plants have an extraordinary diversity of transcription machineries, including five nuclear DNA-dependent RNA polymerases. Four of these enzymes are dedicated to the production of long noncoding RNAs (lncRNAs), which are ribonucleic acids with functions independent of their protein-coding potential. lncRNAs display a broad range of lengths and structures, but they are distinct from the small RNA guides of RNA interference (RNAi) pathways. lncRNAs frequently serve as structural, catalytic, or regulatory molecules for gene expression. They can affect all elements of genes, including promoters, untranslated regions, exons, introns, and terminators, controlling gene expression at various levels, including modifying chromatin accessibility, transcription, splicing, and translation. Certain lncRNAs protect genome integrity, while others respond to environmental cues like temperature, drought, nutrients, and pathogens. In this review, we explain the challenge of defining lncRNAs, introduce the machineries responsible for their production, and organize this knowledge by viewing the functions of lncRNAs throughout the structure of a typical plant gene.
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Affiliation(s)
- Andrzej T Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, USA;
| | - Todd Blevins
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, F-67084 Strasbourg, France;
| | - Szymon Swiezewski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland;
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15
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Ross BT, Zidack NK, Flenniken ML. Extreme Resistance to Viruses in Potato and Soybean. FRONTIERS IN PLANT SCIENCE 2021; 12:658981. [PMID: 33889169 PMCID: PMC8056081 DOI: 10.3389/fpls.2021.658981] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/12/2021] [Indexed: 05/31/2023]
Abstract
Plant pathogens, including viruses, negatively impact global crop production. Plants have evolved complex immune responses to pathogens. These responses are often controlled by nucleotide-binding leucine-rich repeat proteins (NLRs), which recognize intracellular, pathogen-derived proteins. Genetic resistance to plant viruses is often phenotypically characterized by programmed cell death at or near the infection site; a reaction termed the hypersensitive response. Although visualization of the hypersensitive response is often used as a hallmark of resistance, the molecular mechanisms leading to the hypersensitive response and associated cell death vary. Plants with extreme resistance to viruses rarely exhibit symptoms and have little to no detectable virus replication or spread beyond the infection site. Both extreme resistance and the hypersensitive response can be activated by the same NLR genes. In many cases, genes that normally provide an extreme resistance phenotype can be stimulated to cause a hypersensitive response by experimentally increasing cellular levels of pathogen-derived elicitor protein(s). The molecular mechanisms of extreme resistance and its relationship to the hypersensitive response are largely uncharacterized. Studies on potato and soybean cultivars that are resistant to strains of Potato virus Y (PVY), Potato virus X (PVX), and Soybean mosaic virus (SMV) indicate that abscisic acid (ABA)-mediated signaling and NLR nuclear translocation are important for the extreme resistance response. Recent research also indicates that some of the same proteins are involved in both extreme resistance and the hypersensitive response. Herein, we review and synthesize published studies on extreme resistance in potato and soybean, and describe studies in additional species, including model plant species, to highlight future research avenues that may bridge the gaps in our knowledge of plant antiviral defense mechanisms.
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Affiliation(s)
- Brian T. Ross
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
| | - Nina K. Zidack
- Montana State Seed Potato Certification Lab, Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
| | - Michelle L. Flenniken
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
- Montana State Seed Potato Certification Lab, Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
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16
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Fei Y, Nyikó T, Molnar A. Non-perfectly matching small RNAs can induce stable and heritable epigenetic modifications and can be used as molecular markers to trace the origin and fate of silencing RNAs. Nucleic Acids Res 2021; 49:1900-1913. [PMID: 33524108 PMCID: PMC7913690 DOI: 10.1093/nar/gkab023] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 01/04/2021] [Accepted: 01/08/2021] [Indexed: 02/06/2023] Open
Abstract
Short non-coding RNA molecules (sRNAs) play a fundamental role in gene regulation and development in higher organisms. They act as molecular postcodes and guide AGO proteins to target nucleic acids. In plants, sRNA-targeted mRNAs are degraded, reducing gene expression. In contrast, sRNA-targeted DNA sequences undergo cytosine methylation referred to as RNA-directed DNA methylation (RdDM). Cytosine methylation can suppress transcription, thus sRNAs are potent regulators of gene expression. sRNA-mediated RdDM is involved in genome stability through transposon silencing, mobile signalling for epigenetic gene control and hybrid vigour. Since cytosine methylation can be passed on to subsequent generations, RdDM contributes to transgenerational inheritance of the epigenome. Using a novel approach, which can differentiate between primary (inducer) and secondary (amplified) sRNAs, we show that initiation of heritable RdDM does not require complete sequence complementarity between the sRNAs and their nuclear target sequences. sRNAs with up to four regularly interspaced mismatches are potent inducers of RdDM, however, the number and disruptive nature of nucleotide polymorphisms negatively correlate with their efficacy. Our findings contribute to understanding how sRNA can directly shape the epigenome and may be used in designing the next generation of RNA silencing constructs.
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Affiliation(s)
- Yue Fei
- University of Edinburgh, Institute of Molecular Plant Sciences, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Tünde Nyikó
- Agricultural Biotechnology Institute, Szent-Györgyi A. 4., Gödöllő 2100, Hungary
| | - Attila Molnar
- University of Edinburgh, Institute of Molecular Plant Sciences, Max Born Crescent, Edinburgh EH9 3BF, UK
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17
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Palomar VM, Garciarrubio A, Garay-Arroyo A, Martínez-Martínez C, Rosas-Bringas O, Reyes JL, Covarrubias AA. The canonical RdDM pathway mediates the control of seed germination timing under salinity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:691-707. [PMID: 33131171 DOI: 10.1111/tpj.15064] [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: 02/08/2018] [Revised: 09/11/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
Plants respond to adverse environmental cues by adjusting a wide variety of processes through highly regulated mechanisms to maintain plant homeostasis for survival. As a result of the sessile nature of plants, their response, adjustment and adaptation to the changing environment is intimately coordinated with their developmental programs through the crosstalk of regulatory networks. Germination is a critical process in the plant life cycle, and thus plants have evolved various strategies to control the timing of germination according to their local environment. The mechanisms involved in these adjustment responses are largely unknown, however. Here, we report that mutations in core elements of canonical RNA-directed DNA methylation (RdDM) affect the germination and post-germination growth of Arabidopsis seeds grown under salinity stress. Transcriptomic and whole-genome bisulfite sequencing (WGBS) analyses support the involvement of this pathway in the control of germination timing and post-germination growth under salinity stress by preventing the transcriptional activation of genes implicated in these processes. Subsequent transcriptional effects on genes that function in relation to these developmental events support this conclusion.
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Affiliation(s)
- Víctor Miguel Palomar
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Alejandro Garciarrubio
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Adriana Garay-Arroyo
- Laboratorio de Genética Molecular, Desarrollo y Evolución de Plantas, Instituto de Ecología, Universidad Nacional Autónoma de México, Circuito Exterior S/N anexo Jardín Botánico Exterior, Ciudad Universitaria, Ciudad de México, C.P. 04500, México
| | - Coral Martínez-Martínez
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Omar Rosas-Bringas
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - José L Reyes
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
| | - Alejandra A Covarrubias
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, Mor. C.P, 62250, Mexico
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18
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Uslu VV, Bassler A, Krczal G, Wassenegger M. High-Pressure-Sprayed Double Stranded RNA Does Not Induce RNA Interference of a Reporter Gene. FRONTIERS IN PLANT SCIENCE 2020; 11:534391. [PMID: 33391294 PMCID: PMC7773025 DOI: 10.3389/fpls.2020.534391] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 11/18/2020] [Indexed: 05/10/2023]
Abstract
In plants, RNA interference (RNAi) is an effective defense mechanism against pathogens and pests. RNAi mainly involves the micro RNA and the small interfering RNA (siRNA) pathways. The latter pathway is generally based on the processing of long double stranded RNAs (dsRNA) into siRNAs by DICER-LIKE endonucleases (DCLs). SiRNAs are loaded onto ARGONAUTE proteins to constitute the RNA-induced silencing complex (RISC). Natural dsRNAs derive from transcription of inverted repeats or of specific RNA molecules that are transcribed by RNA-directed RNA polymerase 6 (RDR6). Moreover, replication of infecting viruses/viroids results in the production of dsRNA intermediates that can serve as substrates for DCLs. The high effectiveness of RNAi both locally and systemically implicated that plants could become resistant to pathogens, including viruses, through artificial activation of RNAi by topical exogenous application of dsRNA. The most preferable procedure to exploit RNAi would be to simply spray naked dsRNAs onto mature plants that are specific for the attacking pathogens serving as a substitute for pesticides applications. However, the plant cell wall is a difficult barrier to overcome and only few reports claim that topical application of naked dsRNA triggers RNAi in plants. Using a transgenic Nicotiana benthamiana line, we found that high-pressure-sprayed naked dsRNA did not induce silencing of a green fluorescence protein (GFP) reporter gene. Small RNA sequencing (sRNA-seq) of the samples from dsRNA sprayed leaves revealed that the dsRNA was, if at all, not efficiently processed into siRNAs indicating that the dsRNA was insufficiently taken up by plant cells.
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Affiliation(s)
- Veli Vural Uslu
- AlPlanta-Institute for Plant Research, RLP AgroScience GmbH, Neustadt an der Weinstraße, Germany
| | - Alexandra Bassler
- AlPlanta-Institute for Plant Research, RLP AgroScience GmbH, Neustadt an der Weinstraße, Germany
| | - Gabi Krczal
- AlPlanta-Institute for Plant Research, RLP AgroScience GmbH, Neustadt an der Weinstraße, Germany
| | - Michael Wassenegger
- AlPlanta-Institute for Plant Research, RLP AgroScience GmbH, Neustadt an der Weinstraße, Germany
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
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19
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Broad noncoding transcription suggests genome surveillance by RNA polymerase V. Proc Natl Acad Sci U S A 2020; 117:30799-30804. [PMID: 33199612 DOI: 10.1073/pnas.2014419117] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Eukaryotic genomes are pervasively transcribed, yet most transcribed sequences lack conservation or known biological functions. In Arabidopsis thaliana, RNA polymerase V (Pol V) produces noncoding transcripts, which base pair with small interfering RNA (siRNA) and allow specific establishment of RNA-directed DNA methylation (RdDM) on transposable elements. Here, we show that Pol V transcribes much more broadly than previously expected, including subsets of both heterochromatic and euchromatic regions. At already established RdDM targets, Pol V and siRNA work together to maintain silencing. In contrast, some euchromatic sequences do not give rise to siRNA but are covered by low levels of Pol V transcription, which is needed to establish RdDM de novo if a transposon is reactivated. We propose a model where Pol V surveils the genome to make it competent to silence newly activated or integrated transposons. This indicates that pervasive transcription of nonconserved sequences may serve an essential role in maintenance of genome integrity.
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20
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Hung FY, Chen C, Yen MR, Hsieh JWA, Li C, Shih YH, Chen FF, Chen PY, Cui Y, Wu K. The expression of long non-coding RNAs is associated with H3Ac and H3K4me2 changes regulated by the HDA6-LDL1/2 histone modification complex in Arabidopsis. NAR Genom Bioinform 2020; 2:lqaa066. [PMID: 33575615 PMCID: PMC7671367 DOI: 10.1093/nargab/lqaa066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 07/21/2020] [Accepted: 08/25/2020] [Indexed: 01/03/2023] Open
Abstract
In recent years, eukaryotic long non-coding RNAs (lncRNAs) have been identified as important factors involved in a wide variety of biological processes, including histone modification, alternative splicing and transcription enhancement. The expression of lncRNAs is highly tissue-specific and is regulated by environmental stresses. Recently, a large number of plant lncRNAs have been identified, but very few of them have been studied in detail. Furthermore, the mechanism of lncRNA expression regulation remains largely unknown. Arabidopsis HISTONE DEACETYLASE 6 (HDA6) and LSD1-LIKE 1/2 (LDL1/2) can repress gene expression synergistically by regulating H3Ac/H3K4me. In this research, we performed RNA-seq and ChIP-seq analyses to further clarify the function of HDA6-LDL1/2. Our results indicated that the global expression of lncRNAs is increased in hda6/ldl1/2 and that this increased lncRNA expression is particularly associated with H3Ac/H3K4me2 changes. In addition, we found that HDA6-LDL1/2 is important for repressing lncRNAs that are non-expressed or show low-expression, which may be strongly associated with plant development. GO-enrichment analysis also revealed that the neighboring genes of the lncRNAs that are upregulated in hda6/ldl1/2 are associated with various developmental processes. Collectively, our results revealed that the expression of lncRNAs is associated with H3Ac/H3K4me2 changes regulated by the HDA6-LDL1/2 histone modification complex.
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Affiliation(s)
- Fu-Yu Hung
- Institute of Plant Biology, National Taiwan University, Taipei 10617 Taiwan
| | - Chen Chen
- Agriculture and Agri-Food Canada, London Research and Development Centre, London, ON N5V 4T3 Canada
| | - Ming-Ren Yen
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | | | - Chenlong Li
- Agriculture and Agri-Food Canada, London Research and Development Centre, London, ON N5V 4T3 Canada
| | - Yuan-Hsin Shih
- Institute of Plant Biology, National Taiwan University, Taipei 10617 Taiwan
| | - Fang-Fang Chen
- Institute of Plant Biology, National Taiwan University, Taipei 10617 Taiwan
| | - Pao-Yang Chen
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Yuhai Cui
- Agriculture and Agri-Food Canada, London Research and Development Centre, London, ON N5V 4T3 Canada
| | - Keqiang Wu
- Institute of Plant Biology, National Taiwan University, Taipei 10617 Taiwan
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21
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Zhou HR, Lin RN, Huang HW, Li L, Cai T, Zhu JK, Chen S, He XJ. The CCR4-NOT complex component NOT1 regulates RNA-directed DNA methylation and transcriptional silencing by facilitating Pol IV-dependent siRNA production. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:1503-1515. [PMID: 32412137 DOI: 10.1111/tpj.14818] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/29/2020] [Accepted: 05/07/2020] [Indexed: 05/20/2023]
Abstract
Small interfering RNAs (siRNAs) are responsible for establishing and maintaining DNA methylation through the RNA-directed DNA methylation (RdDM) pathway in plants. Although siRNA biogenesis is well known, it is relatively unclear about how the process is regulated. By a forward genetic screen in Arabidopsis thaliana, we identified a mutant defective in NOT1 and demonstrated that NOT1 is required for transcriptional silencing at RdDM target genomic loci. We demonstrated that NOT1 is required for Pol IV-dependent siRNA accumulation and DNA methylation at a subset of RdDM target genomic loci. Furthermore, we revealed that NOT1 is a constituent of a multi-subunit CCR4-NOT deadenylase complex by immunoprecipitation combined with mass spectrometry and demonstrated that the CCR4-NOT components can function as a whole to mediate chromatin silencing. Therefore, our work establishes that the CCR4-NOT complex regulates the biogenesis of Pol IV-dependent siRNAs, and hence facilitates DNA methylation and transcriptional silencing in Arabidopsis.
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Affiliation(s)
- Hao-Ran Zhou
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Rong-Nan Lin
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Huan-Wei Huang
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Lin Li
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Tao Cai
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - She Chen
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Xin-Jian He
- National Institute of Biological Sciences, Beijing, 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
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22
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Liu Y, Han Y, Zhou L, Pan X, Sun X, Liu Y, Liang M, Qin J, Lu Y, Liu P. A comprehensive evaluation of computational tools to identify differential methylation regions using RRBS data. Genomics 2020; 112:4567-4576. [PMID: 32712292 DOI: 10.1016/j.ygeno.2020.07.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 07/20/2020] [Indexed: 01/01/2023]
Abstract
DNA methylation plays a vital role in transcription regulation. Reduced representation bisulfite sequencing (RRBS) is becoming common for analyzing genome-wide methylation profiles at the single nucleotide level. A major goal of RRBS studies is to detect differentially methylated regions (DMRs) between different biological conditions. The previous tools to predict DMRs lack consistency. Here, we simulated RRBS datasets with significant attributes of real sequencing data under a wide range of scenarios, and systematically evaluated seven DMR detection tools in terms of type I error rate, precision/recall (PR), and area under ROC curve (AUC) using different methylation levels, sequencing coverage depth, length of DMRs, read length, and sample sizes. DMRfinder, methylSig, and methylKit were our preferred tools for RRBS data analysis, in terms of their AUC and PR curves. Our comparison highlights the different applicability of DMR detection tools and provides information to guide researchers towards the advancement of sequence-based DMR analysis.
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Affiliation(s)
- Yi Liu
- Department of Respiratory Medicine, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Yi Han
- Department of Respiratory Medicine, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Liyuan Zhou
- Department of Respiratory Medicine, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Xiaoqing Pan
- Center of Systems Molecular Medicine, Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Xiwei Sun
- Department of Respiratory Medicine, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Yong Liu
- Center of Systems Molecular Medicine, Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Mingyu Liang
- Center of Systems Molecular Medicine, Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Jiale Qin
- Center for Uterine Cancer Diagnosis & Therapy Research of Zhejiang Province, Women's Reproductive Health Key Laboratory of Zhejiang Province, Department of Gynecologic Oncology, Women's Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310029, China.
| | - Yan Lu
- Center for Uterine Cancer Diagnosis & Therapy Research of Zhejiang Province, Women's Reproductive Health Key Laboratory of Zhejiang Province, Department of Gynecologic Oncology, Women's Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310029, China.
| | - Pengyuan Liu
- Department of Respiratory Medicine, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China; Center of Systems Molecular Medicine, Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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23
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Small RNA Function in Plants: From Chromatin to the Next Generation. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2020; 84:133-140. [PMID: 32518093 DOI: 10.1101/sqb.2019.84.040394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Small RNA molecules can target a particular virus, gene, or transposable element (TE) with a high degree of specificity. Their ability to move from cell to cell and recognize targets in trans also allows building networks capable of regulating a large number of related targets at once. In the case of epigenetic silencing, small RNA may use the widespread distribution of TEs in eukaryotic genomes to coordinate many loci across developmental and generational time. Here, we discuss the intriguing role of plant small RNA in targeting transposons and repeats in pollen and seeds. Epigenetic reprogramming in the germline and early seed development provides a mechanism to control genome dosage, imprinted gene expression, and incompatible hybridizations via the "triploid block."
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24
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Dalakouras A, Papadopoulou KK. Epigenetic Modifications: An Unexplored Facet of Exogenous RNA Application in Plants. PLANTS 2020; 9:plants9060673. [PMID: 32466487 PMCID: PMC7356522 DOI: 10.3390/plants9060673] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 05/22/2020] [Accepted: 05/23/2020] [Indexed: 01/09/2023]
Abstract
Exogenous RNA interference (exo-RNAi) is a powerful transgene-free tool in modern crop improvement and protection platforms. In exo-RNAi approaches, double-stranded RNAs (dsRNAs) or short-interfering RNAs (siRNAs) are externally applied in plants in order to selectively trigger degradation of target mRNAs. Yet, the applied dsRNAs may also trigger unintended epigenetic alterations and result in epigenetically modified plants, an issue that has not been sufficiently addressed and which merits more careful consideration.
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Affiliation(s)
- Athanasios Dalakouras
- Department of Biochemistry & Biotechnology, University of Thessaly, 41500 Larissa, Greece;
- Institute of Plant Breeding and Genetic Resources ELGO-DEMETER, 57001 Thessaloniki, Greece
- Correspondence:
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25
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Yu J, Xu F, Wei Z, Zhang X, Chen T, Pu L. Epigenomic landscape and epigenetic regulation in maize. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:1467-1489. [PMID: 31965233 DOI: 10.1007/s00122-020-03549-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 01/14/2020] [Indexed: 05/12/2023]
Abstract
Epigenetic regulation has been implicated in the control of multiple agronomic traits in maize. Here, we review current advances in our understanding of epigenetic regulation, which has great potential for improving agronomic traits and the environmental adaptability of crops. Epigenetic regulation plays vital role in the control of complex agronomic traits. Epigenetic variation could contribute to phenotypic diversity and can be used to improve the quality and productivity of crops. Maize (Zea mays L.), one of the most widely cultivated crops for human food, animal feed, and ethanol biofuel, is a model plant for genetic studies. Recent advances in high-throughput sequencing technology have made possible the study of epigenetic regulation in maize on a genome-wide scale. In this review, we discuss recent epigenetic studies in maize many achieved by Chinese research groups. These studies have explored the roles of DNA methylation, posttranslational modifications of histones, chromatin remodeling, and noncoding RNAs in the regulation of gene expression in plant development and environment response. We also provide our future prospects for manipulating epigenetic regulation to improve crops.
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Affiliation(s)
- Jia Yu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fan Xu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ziwei Wei
- School of Life Sciences, Anhui Agricultural University, Hefei, China
| | - Xiangxiang Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Tao Chen
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Li Pu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.
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26
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Wang Z, Butel N, Santos-González J, Borges F, Yi J, Martienssen RA, Martinez G, Köhler C. Polymerase IV Plays a Crucial Role in Pollen Development in Capsella. THE PLANT CELL 2020; 32:950-966. [PMID: 31988265 PMCID: PMC7145478 DOI: 10.1105/tpc.19.00938] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/13/2020] [Accepted: 01/21/2020] [Indexed: 05/04/2023]
Abstract
In Arabidopsis (Arabidopsis thaliana), DNA-dependent RNA polymerase IV (Pol IV) is required for the formation of transposable element (TE)-derived small RNA transcripts. These transcripts are processed by DICER-LIKE3 into 24-nucleotide small interfering RNAs (siRNAs) that guide RNA-directed DNA methylation. In the pollen grain, Pol IV is also required for the accumulation of 21/22-nucleotide epigenetically activated siRNAs, which likely silence TEs via post-transcriptional mechanisms. Despite this proposed role of Pol IV, its loss of function in Arabidopsis does not cause a discernible pollen defect. Here, we show that the knockout of NRPD1, encoding the largest subunit of Pol IV, in the Brassicaceae species Capsella (Capsella rubella), caused postmeiotic arrest of pollen development at the microspore stage. As in Arabidopsis, all TE-derived siRNAs were depleted in Capsella nrpd1 microspores. In the wild-type background, the same TEs produced 21/22-nucleotide and 24-nucleotide siRNAs; these processes required Pol IV activity. Arrest of Capsella nrpd1 microspores was accompanied by the deregulation of genes targeted by Pol IV-dependent siRNAs. TEs were much closer to genes in Capsella compared with Arabidopsis, perhaps explaining the essential role of Pol IV in pollen development in Capsella. Our discovery that Pol IV is functionally required in Capsella microspores emphasizes the relevance of investigating different plant models.
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Affiliation(s)
- Zhenxing Wang
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Nicolas Butel
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Juan Santos-González
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Filipe Borges
- Howard Hughes Medical Institute and Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Jun Yi
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Robert A Martienssen
- Howard Hughes Medical Institute and Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - German Martinez
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Claudia Köhler
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
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27
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Zhou J, Liu L, Li Q, Xu W, Li K, Wang ZW, Sun Q. Intronic heterochromatin prevents cryptic transcription initiation in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:1185-1197. [PMID: 31647592 DOI: 10.1111/tpj.14584] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/06/2019] [Accepted: 10/17/2019] [Indexed: 06/10/2023]
Abstract
Intronic transposable elements (TEs) comprise a large proportion in eukaryotic genomes, but how they regulate the host genes remains to be explored. Our forward genetic screen disclosed the plant-specific RNA polymerases IV and V in suppressing intronic TE-mediated cryptic transcription initiation of a chimeric transcripts at FLC (FLCTE ). Initiation of FLCTE transcription is blocked by the locally formed intronic heterochromatin, which is directly associated with RNA Pol V to inhibit the entry of RNA Pol II and the occupancy of H3K4 methylation. Genome-wide Pol II Ser5p native elongation transcription sequencing revealed that a significant number of intronic heterochromatin-containing genes undergo this mechanism. This study sheds light on deeply understanding the function of intronic heterochromatin on host genes expression in eukaryotic genome.
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Affiliation(s)
- Jincong Zhou
- Tsinghua-Peking Joint Center for Life Sciences and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Liangyu Liu
- Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing Municipal Government, College of Life Sciences, Capital Normal University, Beijing, China
| | - Qin Li
- Tsinghua-Peking Joint Center for Life Sciences and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Wei Xu
- Tsinghua-Peking Joint Center for Life Sciences and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Kuan Li
- Tsinghua-Peking Joint Center for Life Sciences and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhi-Wei Wang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Qianwen Sun
- Tsinghua-Peking Joint Center for Life Sciences and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
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28
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Cytosine Methylation Affects the Mutability of Neighboring Nucleotides in Germline and Soma. Genetics 2020; 214:809-823. [PMID: 32079595 DOI: 10.1534/genetics.120.303028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 02/12/2020] [Indexed: 02/07/2023] Open
Abstract
Methylated cytosines deaminate at higher rates than unmethylated cytosines, and the lesions they produce are repaired less efficiently. As a result, methylated cytosines are mutational hotspots. Here, combining rare polymorphism and base-resolution methylation data in humans, Arabidopsis thaliana, and rice (Oryza sativa), we present evidence that methylation state affects mutation dynamics not only at the focal cytosine but also at neighboring nucleotides. In humans, contrary to prior suggestions, we find that nucleotides in the close vicinity (±3 bp) of methylated cytosines mutate less frequently. Reduced mutability around methylated CpGs is also observed in cancer genomes, considering single nucleotide variants alongside tissue-of-origin-matched methylation data. In contrast, methylation is associated with increased neighborhood mutation risk in A. thaliana and rice. The difference in neighborhood mutation risk is less pronounced further away from the focal CpG and modulated by regional GC content. Our results are consistent with a model where altered risk at neighboring bases is linked to lesion formation at the focal CpG and subsequent long-patch repair. Our findings indicate that cytosine methylation has a broader mutational footprint than is commonly assumed.
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29
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Wang HLV, Chekanova JA. Novel mRNAs 3' end-associated cis-regulatory elements with epigenomic signatures of mammalian enhancers in the Arabidopsis genome. RNA (NEW YORK, N.Y.) 2019; 25:1242-1258. [PMID: 31311821 PMCID: PMC6800480 DOI: 10.1261/rna.071209.119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 07/04/2019] [Indexed: 06/10/2023]
Abstract
The precise spatial and temporal control of gene expression requires the coordinated action of genomic cis-regulatory elements (CREs), including transcriptional enhancers. However, our knowledge of enhancers in plants remains rudimentary and only a few plant enhancers have been experimentally defined. Here, we screened the Arabidopsis thaliana genome and identified >1900 unique candidate CREs that carry the genomic signatures of mammalian enhancers. These were termed putative enhancer-like elements (PEs). Nearly all PEs are intragenic and, unexpectedly, most associate with the 3' ends of protein-coding genes. PEs are hotspots for transcription factor binding and harbor motifs resembling cleavage/polyadenylation signals, potentially coupling 3' end processing to the transcriptional regulation of other genes. Hi-C data showed that 24% of PEs are located at regions that can interact intrachromosomally with other protein-coding genes and, surprisingly, many of these target genes interact with PEs through their 3' UTRs. Examination of the genomes of 1135 sequenced Arabidopsis accessions showed that PEs are conserved. Our findings suggest that the identified PEs may serve as transcriptional enhancers and sites for mRNA 3' end processing, and constitute a novel group of CREs in Arabidopsis.
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Affiliation(s)
- Hsiao-Lin V Wang
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Julia A Chekanova
- Mycological Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
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30
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Guzmán-Benito I, Donaire L, Amorim-Silva V, Vallarino JG, Esteban A, Wierzbicki AT, Ruiz-Ferrer V, Llave C. The immune repressor BIR1 contributes to antiviral defense and undergoes transcriptional and post-transcriptional regulation during viral infections. THE NEW PHYTOLOGIST 2019; 224:421-438. [PMID: 31111491 PMCID: PMC6711825 DOI: 10.1111/nph.15931] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 05/15/2019] [Indexed: 06/09/2023]
Abstract
BIR1 is a receptor-like kinase that functions as a negative regulator of basal immunity and cell death in Arabidopsis. Using Arabidopsis thaliana and Tobacco rattle virus (TRV), we investigate the antiviral role of BIR1, the molecular mechanisms of BIR1 gene expression regulation during viral infections, and the effects of BIR1 overexpression on plant immunity and development. We found that SA acts as a signal molecule for BIR1 activation during infection. Inactivating mutations of BIR1 in the bir1-1 mutant cause strong antiviral resistance independently of constitutive cell death or SA defense priming. BIR1 overexpression leads to severe developmental defects, cell death and premature death, which correlate with the constitutive activation of plant immune responses. Our findings suggest that BIR1 acts as a negative regulator of antiviral defense in plants, and indicate that RNA silencing contributes, alone or in conjunction with other regulatory mechanisms, to define a threshold expression for proper BIR1 function beyond which an autoimmune response may occur. This work provides novel mechanistic insights into the regulation of BIR1 homeostasis that may be common for other plant immune components.
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Affiliation(s)
- Irene Guzmán-Benito
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
- Doctorado en Biotecnología y Recursos Genéticos de Plantas y Microorganismos Asociados, ETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040-Madrid, Spain
| | - Livia Donaire
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
| | - Vítor Amorim-Silva
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea “La Mayora”, Universidad de Málaga-CSIC (IHSM-UMA-CSIC), Universidad de Málaga, Campus Teatinos, 29071-Málaga, Spain
| | - José G. Vallarino
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea “La Mayora”, Universidad de Málaga-CSIC (IHSM-UMA-CSIC), Universidad de Málaga, Campus Teatinos, 29071-Málaga, Spain
| | - Alicia Esteban
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea “La Mayora”, Universidad de Málaga-CSIC (IHSM-UMA-CSIC), Universidad de Málaga, Campus Teatinos, 29071-Málaga, Spain
| | - Andrzej T. Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Virginia Ruiz-Ferrer
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
| | - César Llave
- Departmento de Biotecnología Microbiana y de Plantas, Centro de Investigaciones Biológicas, CSIC, 28040-Madrid, Spain
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31
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Diezma‐Navas L, Pérez‐González A, Artaza H, Alonso L, Caro E, Llave C, Ruiz‐Ferrer V. Crosstalk between epigenetic silencing and infection by tobacco rattle virus in Arabidopsis. MOLECULAR PLANT PATHOLOGY 2019; 20:1439-1452. [PMID: 31274236 PMCID: PMC6792132 DOI: 10.1111/mpp.12850] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
DNA methylation is an important epigenetic mechanism for controlling innate immunity against microbial pathogens in plants. Little is known, however, about the manner in which viral infections interact with DNA methylation pathways. Here we investigate the crosstalk between epigenetic silencing and viral infections in Arabidopsis inflorescences. We found that tobacco rattle virus (TRV) causes changes in the expression of key transcriptional gene silencing factors with RNA-directed DNA methylation activities that coincide with changes in methylation at the whole genome level. Viral susceptibility/resistance was altered in DNA (de)methylation-deficient mutants, suggesting that DNA methylation is an important regulatory system controlling TRV proliferation. We further show that several transposable elements (TEs) underwent transcriptional activation during TRV infection, and that TE regulation likely involved both DNA methylation-dependent and -independent mechanisms. We identified a cluster of disease resistance genes regulated by DNA methylation in infected plants that were enriched for TEs in their promoters. Interestingly, TEs and nearby resistance genes were co-regulated in TRV-infected DNA (de)methylation mutants. Our study shows that DNA methylation contributes to modulate the outcome of viral infections in Arabidopsis, and opens up new possibilities for exploring the role of TE regulation in antiviral defence.
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Affiliation(s)
- Laura Diezma‐Navas
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones BiológicasCSICRamiro de Maeztu 9MadridSpain
- Doctorado en Biotecnología y Recursos Genéticos de Plantas y Microorganismos AsociadosETSI Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid28040MadridSpain
| | - Ana Pérez‐González
- Centro de Biotecnología y Genómica de PlantasUniversidad Politécnica de Madrid (UPM)Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA)Campus de Montegancedo UPM28223Pozuelo de Alarcón, MadridSpain
| | - Haydeé Artaza
- Bionformatic and Statistic Service, Centro de Investigaciones BiológicasCSICRamiro de Maeztu 928040MadridSpain
- Present address:
Department of Clinical ScienceUniversity of Bergen5020BergenNorway
| | - Lola Alonso
- Bionformatic and Statistic Service, Centro de Investigaciones BiológicasCSICRamiro de Maeztu 928040MadridSpain
- Present address:
Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center (CNIO)MadridSpain
| | - Elena Caro
- Centro de Biotecnología y Genómica de PlantasUniversidad Politécnica de Madrid (UPM)Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA)Campus de Montegancedo UPM28223Pozuelo de Alarcón, MadridSpain
| | - César Llave
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones BiológicasCSICRamiro de Maeztu 9MadridSpain
| | - Virginia Ruiz‐Ferrer
- Department of Microbial and Plant Biotechnology, Centro de Investigaciones BiológicasCSICRamiro de Maeztu 9MadridSpain
- Present address:
Department of Plant Physiology, Plant Biotechnology and Molecular Biology Group. Environmental Sciences and Biochemistry SchoolCastilla‐La Mancha UniversityToledoSpain
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32
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Abstract
DNA methylation is a conserved epigenetic modification that is important for gene regulation and genome stability. Aberrant patterns of DNA methylation can lead to plant developmental abnormalities. A specific DNA methylation state is an outcome of dynamic regulation by de novo methylation, maintenance of methylation and active demethylation, which are catalysed by various enzymes that are targeted by distinct regulatory pathways. In this Review, we discuss DNA methylation in plants, including methylating and demethylating enzymes and regulatory factors, and the coordination of methylation and demethylation activities by a so-called methylstat mechanism; the functions of DNA methylation in regulating transposon silencing, gene expression and chromosome interactions; the roles of DNA methylation in plant development; and the involvement of DNA methylation in plant responses to biotic and abiotic stress conditions.
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Iwasaki M, Hyvärinen L, Piskurewicz U, Lopez-Molina L. Non-canonical RNA-directed DNA methylation participates in maternal and environmental control of seed dormancy. eLife 2019; 8:37434. [PMID: 30910007 PMCID: PMC6435323 DOI: 10.7554/elife.37434] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 03/09/2019] [Indexed: 12/29/2022] Open
Abstract
Seed dormancy is an adaptive trait preventing premature germination out of season. In a previous report (Piskurewicz et al., 2016) we showed that dormancy levels are maternally inherited through the preferential maternal allele expression in the seed endosperm of ALLANTOINASE (ALN), a negative regulator of dormancy. Here we show that suppression of ALN paternal allele expression is imposed by non-canonical RNA-directed DNA methylation (RdDM) of the paternal ALN allele promoter. Dormancy levels are further enhanced by cold during seed development. We show that DNA methylation of the ALN promoter is stimulated by cold in a tissue-specific manner through non-canonical RdDM, involving RDR6 and AGO6. This leads to suppression of ALN expression and further promotion of seed dormancy. Our results suggest that tissue-specific and cold-induced RdDM is superimposed to parental allele imprints to deposit in the seed progeny a transient memory of environmental conditions experienced by the mother plant.
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Affiliation(s)
- Mayumi Iwasaki
- Department of Plant Biology, University of Geneva, Geneva, Switzerland
| | - Lena Hyvärinen
- Department of Plant Biology, University of Geneva, Geneva, Switzerland
| | | | - Luis Lopez-Molina
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
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34
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Lee CH, Carroll BJ. Evolution and Diversification of Small RNA Pathways in Flowering Plants. PLANT & CELL PHYSIOLOGY 2018; 59:2169-2187. [PMID: 30169685 DOI: 10.1093/pcp/pcy167] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 08/30/2018] [Indexed: 06/08/2023]
Abstract
Small regulatory RNAs guide gene silencing at the DNA or RNA level through repression of complementary sequences. The two main forms of small RNAs are microRNA (miRNA) and small interfering RNA (siRNAs), which are generated from the processing of different forms of double-stranded RNA (dsRNA) precursors. These two forms of small regulatory RNAs function in distinct but overlapping gene silencing pathways in plants. Gene silencing pathways in eukaryotes evolved from an ancient prokaryotic mechanism involved in genome defense against invasive genetic elements, but has since diversified to also play a crucial role in regulation of endogenous gene expression. Here, we review the biogenesis of the different forms of small RNAs in plants, including miRNAs, phased, secondary siRNAs (phasiRNAs) and heterochromatic siRNAs (hetsiRNAs), with a focus on their functions in genome defense, transcriptional and post-transcriptional gene silencing, RNA-directed DNA methylation, trans-chromosomal methylation and paramutation. We also discuss the important role that gene duplication has played in the functional diversification of gene silencing pathways in plants, and we highlight recently discovered components of gene silencing pathways in plants.
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Affiliation(s)
- Chin Hong Lee
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia
| | - Bernard J Carroll
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia
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35
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Čermák V, Fischer L. Pervasive read-through transcription of T-DNAs is frequent in tobacco BY-2 cells and can effectively induce silencing. BMC PLANT BIOLOGY 2018; 18:252. [PMID: 30348096 PMCID: PMC6196474 DOI: 10.1186/s12870-018-1482-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 10/12/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Plant transformation via Agrobacterium tumefaciens is characterized by integration of commonly low number of T-DNAs at random positions in the genome. When integrated into an active gene region, promoterless reporter genes placed near the T-DNA border sequence are frequently transcribed and even translated to reporter proteins, which is the principle of promoter- and gene-trap lines. RESULTS Here we show that even internal promotorless regions of T-DNAs are often transcribed. Such spontaneous transcription was observed in the majority of independently transformed tobacco BY-2 lines (over 65%) and it could effectively induce silencing if an inverted repeat was present within the T-DNA. We documented that the transcription often occurred in both directions. It was not directly connected with any regulatory elements present within the T-DNAs and at least some of the transcripts were initiated outside of the T-DNA. The likeliness of this read-through transcription seemed to increase in lines with higher T-DNA copy number. Splicing and presence of a polyA tail in the transcripts indicated involvement of Pol II, but surprisingly, the transcription was able to run across two transcription terminators present within the T-DNA. Such pervasive transcription was observed with three different T-DNAs in BY-2 cells and with lower frequency was also detected in Arabidopsis thaliana. CONCLUSIONS Our results demonstrate unexpected pervasive read-through transcription of T-DNAs. We hypothesize that it was connected with a specific chromatin state of newly integrated DNA, possibly affected by the adjacent genomic region. Although this phenomenon can be easily overlooked, it can have significant consequences when working with highly sensitive systems like RNAi induction using an inverted repeat construct, so it should be generally considered when interpreting results obtained with the transgenic technology.
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Affiliation(s)
- Vojtěch Čermák
- Department of Experimental Plant Biology, Charles University, Faculty of Science, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Lukáš Fischer
- Department of Experimental Plant Biology, Charles University, Faculty of Science, Viničná 5, 128 44 Prague 2, Czech Republic
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36
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van Wonterghem M, Thieffry A, Boyd M, Bornholdt J, Brodersen P. A new class of genic nuclear RNA species in Arabidopsis. FEBS Lett 2018; 592:631-643. [PMID: 29355922 DOI: 10.1002/1873-3468.12981] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 01/01/2018] [Accepted: 01/16/2018] [Indexed: 11/07/2022]
Abstract
Targeting of ArabidopsisPHABULOSA (PHB) mRNA by miR166 has been implicated in gene body methylation at the PHB locus. We report that the PHB locus produces an array of stable nuclear RNA species that are neither polyadenylated nor capped. Their biogenesis requires neither RNA polymerases IV/V nor miR166-guided cleavage. The PHB RNAs are insensitive to mutation of nuclear RNA decay pathways and are conserved in several Brassicaceae species, suggesting functional relevance. Similar RNA species are also produced by another body-methylated locus encoding the miR414 target eIF2. Our data reveal the existence of a new class of genic nuclear RNA species.
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Affiliation(s)
| | - Axel Thieffry
- Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen N, Denmark
| | - Mette Boyd
- Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen N, Denmark
| | - Jette Bornholdt
- Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen N, Denmark
| | - Peter Brodersen
- Department of Biology, University of Copenhagen, Copenhagen N, Denmark
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37
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McKinlay A, Podicheti R, Wendte JM, Cocklin R, Rusch DB. RNA polymerases IV and V influence the 3' boundaries of Polymerase II transcription units in Arabidopsis. RNA Biol 2017; 15:269-279. [PMID: 29199514 DOI: 10.1080/15476286.2017.1409930] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Nuclear multisubunit RNA polymerases IV and V (Pol IV and Pol V) evolved in plants as specialized forms of Pol II. Their functions are best understood in the context of RNA-directed DNA methylation (RdDM), a process in which Pol IV-dependent 24 nt siRNAs direct the de novo cytosine methylation of regions transcribed by Pol V. Pol V has additional functions, independent of Pol IV and 24 nt siRNA biogenesis, in maintaining the repression of transposons and genomic repeats whose silencing depends on maintenance cytosine methylation. Here we report that Pol IV and Pol V play unexpected roles in defining the 3' boundaries of Pol II transcription units. Nuclear run-on assays reveal that in the absence of Pol IV or Pol V, Pol II occupancy downstream of poly A sites increases for approximately 12% of protein-coding genes. This effect is most pronounced for convergently transcribed gene pairs. Although Pols IV and V are detected near transcript ends of the affected Pol II - transcribed genes, their role in limiting Pol II read-through is independent of siRNA biogenesis or cytosine methylation for the majority of these genes. Interestingly, we observed that splicing was less efficient in pol IV or pol V mutant plants, compared to wild-type plants, suggesting that Pol IV or Pol V might affect pre-mRNA processing. We speculate that Pols IV and V (and/or their associated factors) play roles in Pol II transcription termination and pre-mRNA splicing by influencing polymerase elongation rates and/or release at collision sites for convergent genes.
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Affiliation(s)
- Anastasia McKinlay
- a Department of Biology , Indiana University , Bloomington , Indiana , USA
| | - Ram Podicheti
- b Center for Genomics and Bioinformatics, Indiana University , Bloomington , Indiana , USA.,c School of Informatics and Computing, Indiana University , Bloomington , IN , USA
| | - Jered M Wendte
- a Department of Biology , Indiana University , Bloomington , Indiana , USA
| | - Ross Cocklin
- a Department of Biology , Indiana University , Bloomington , Indiana , USA.,d Howard Hughes Medical Institute, Indiana University , Bloomington , Indiana
| | - Douglas B Rusch
- b Center for Genomics and Bioinformatics, Indiana University , Bloomington , Indiana , USA
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Marasco M, Li W, Lynch M, Pikaard CS. Catalytic properties of RNA polymerases IV and V: accuracy, nucleotide incorporation and rNTP/dNTP discrimination. Nucleic Acids Res 2017; 45:11315-11326. [PMID: 28977461 PMCID: PMC5737373 DOI: 10.1093/nar/gkx794] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 08/29/2017] [Indexed: 02/05/2023] Open
Abstract
All eukaryotes have three essential nuclear multisubunit RNA polymerases, abbreviated as Pol I, Pol II and Pol III. Plants are remarkable in having two additional multisubunit RNA polymerases, Pol IV and Pol V, which synthesize noncoding RNAs that coordinate RNA-directed DNA methylation for silencing of transposons and a subset of genes. Based on their subunit compositions, Pols IV and V clearly evolved as specialized forms of Pol II, but their catalytic properties remain undefined. Here, we show that Pols IV and V differ from one another, and Pol II, in nucleotide incorporation rate, transcriptional accuracy and the ability to discriminate between ribonucleotides and deoxyribonucleotides. Pol IV transcription is considerably more error-prone than Pols II or V, which may be tolerable in its synthesis of short RNAs that serve as precursors for siRNAs targeting non-identical members of transposon families. By contrast, Pol V exhibits high fidelity transcription, similar to Pol II, suggesting a need for Pol V transcripts to faithfully reflect the DNA sequence of target loci to which siRNA–Argonaute silencing complexes are recruited.
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Affiliation(s)
- Michelle Marasco
- Department of Biology, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA
| | - Weiyi Li
- Department of Biology, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA
| | - Michael Lynch
- Department of Biology, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA
| | - Craig S Pikaard
- Department of Biology, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA.,Howard Hughes Medical Institute, Indiana University, Bloomington, IN 47405, USA
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Au PCK, Dennis ES, Wang MB. Analysis of Argonaute 4-Associated Long Non-Coding RNA in Arabidopsis thaliana Sheds Novel Insights into Gene Regulation through RNA-Directed DNA Methylation. Genes (Basel) 2017; 8:E198. [PMID: 28783101 PMCID: PMC5575662 DOI: 10.3390/genes8080198] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 12/20/2022] Open
Abstract
RNA-directed DNA methylation (RdDM) is a plant-specific de novo DNA methylation mechanism that requires long noncoding RNA (lncRNA) as scaffold to define target genomic loci. While the role of RdDM in maintaining genome stability is well established, how it regulates protein-coding genes remains poorly understood and few RdDM target genes have been identified. In this study, we obtained sequences of RdDM-associated lncRNAs using nuclear RNA immunoprecipitation against ARGONAUTE 4 (AGO4), a key component of RdDM that binds specifically with the lncRNA. Comparison of these lncRNAs with gene expression data of RdDM mutants identified novel RdDM target genes. Surprisingly, a large proportion of these target genes were repressed in RdDM mutants suggesting that they are normally activated by RdDM. These RdDM-activated genes are more enriched for gene body lncRNA than the RdDM-repressed genes. Histone modification and RNA analyses of several RdDM-activated stress response genes detected increased levels of active histone mark and short RNA transcript in the lncRNA-overlapping gene body regions in the ago4 mutant despite the repressed expression of these genes. These results suggest that RdDM, or AGO4, may play a role in maintaining or activating stress response gene expression by directing gene body chromatin modification preventing cryptic transcription.
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Affiliation(s)
- Phil Chi Khang Au
- Commonwealth Scientific and Industrial Research Organisation Agriculture, Canberra, Australian Capital Territory 2601, Australia.
| | - Elizabeth S Dennis
- Commonwealth Scientific and Industrial Research Organisation Agriculture, Canberra, Australian Capital Territory 2601, Australia.
| | - Ming-Bo Wang
- Commonwealth Scientific and Industrial Research Organisation Agriculture, Canberra, Australian Capital Territory 2601, Australia.
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40
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Long-range control of gene expression via RNA-directed DNA methylation. PLoS Genet 2017; 13:e1006749. [PMID: 28475589 PMCID: PMC5438180 DOI: 10.1371/journal.pgen.1006749] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 05/19/2017] [Accepted: 04/07/2017] [Indexed: 01/14/2023] Open
Abstract
RNA-mediated transcriptional silencing, in plants known as RNA-directed DNA methylation (RdDM), is a conserved process where small interfering RNA (siRNA) and long non-coding RNA (lncRNA) help establish repressive chromatin modifications. This process represses transposons and affects the expression of protein-coding genes. We found that in Arabidopsis thaliana AGO4 binding sites are often located distant from genes differentially expressed in ago4. Using Hi-C to compare interactions between genotypes, we show that RdDM-targeted loci have the potential to engage in chromosomal interactions, but these interactions are inhibited in wild-type conditions. In mutants defective in RdDM, the frequency of chromosomal interactions at RdDM targets is increased. This includes increased frequency of interactions between Pol V methylated sites and distal genes that are repressed by RdDM. We propose a model, where RdDM prevents the formation of chromosomal interactions between genes and their distant regulatory elements.
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41
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Noronha Fernandes-Brum C, Marinho Rezende P, Cherubino Ribeiro TH, Ricon de Oliveira R, Cunha de Sousa Cardoso T, Rodrigues do Amaral L, de Souza Gomes M, Chalfun-Junior A. A genome-wide analysis of the RNA-guided silencing pathway in coffee reveals insights into its regulatory mechanisms. PLoS One 2017; 12:e0176333. [PMID: 28448529 PMCID: PMC5407642 DOI: 10.1371/journal.pone.0176333] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 04/10/2017] [Indexed: 11/28/2022] Open
Abstract
microRNAs (miRNAs) are derived from self-complementary hairpin structures, while small-interfering RNAs (siRNAs) are derived from double-stranded RNA (dsRNA) or hairpin precursors. The core mechanism of sRNA production involves DICER-like (DCL) in processing the smallRNAs (sRNAs) and ARGONAUTE (AGO) as effectors of silencing, and siRNA biogenesis also involves action of RNA-Dependent RNA Polymerase (RDR), Pol IV and Pol V in biogenesis. Several other proteins interact with the core proteins to guide sRNA biogenesis, action, and turnover. We aimed to unravel the components and functions of the RNA-guided silencing pathway in a non-model plant species of worldwide economic relevance. The sRNA-guided silencing complex members have been identified in the Coffea canephora genome, and they have been characterized at the structural, functional, and evolutionary levels by computational analyses. Eleven AGO proteins, nine DCL proteins (which include a DCL1-like protein that was not previously annotated), and eight RDR proteins were identified. Another 48 proteins implicated in smallRNA (sRNA) pathways were also identified. Furthermore, we identified 235 miRNA precursors and 317 mature miRNAs from 113 MIR families, and we characterized ccp-MIR156, ccp-MIR172, and ccp-MIR390. Target prediction and gene ontology analyses of 2239 putative targets showed that significant pathways in coffee are targeted by miRNAs. We provide evidence of the expansion of the loci related to sRNA pathways, insights into the activities of these proteins by domain and catalytic site analyses, and gene expression analysis. The number of MIR loci and their targeted pathways highlight the importance of miRNAs in coffee. We identified several roles of sRNAs in C. canephora, which offers substantial insight into better understanding the transcriptional and post-transcriptional regulation of this major crop.
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Affiliation(s)
- Christiane Noronha Fernandes-Brum
- Department of Biology, Section of Plant Physiology, Laboratory of Plant Molecular Physiology (LFMP), Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil
| | - Pâmela Marinho Rezende
- Department of Biology, Section of Plant Physiology, Laboratory of Plant Molecular Physiology (LFMP), Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil
| | - Thales Henrique Cherubino Ribeiro
- Department of Biology, Section of Plant Physiology, Laboratory of Plant Molecular Physiology (LFMP), Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil
| | | | - Thaís Cunha de Sousa Cardoso
- Institute of Genetics and Biochemistry (INGEB),Laboratory of Bioinformatics and Molecular Analysis (LBAM), Federal University of Uberlândia (UFU)- Campus Patos de Minas, Patos de Minas, Minas Gerais, Brasil
| | - Laurence Rodrigues do Amaral
- Institute of Genetics and Biochemistry (INGEB),Laboratory of Bioinformatics and Molecular Analysis (LBAM), Federal University of Uberlândia (UFU)- Campus Patos de Minas, Patos de Minas, Minas Gerais, Brasil
| | - Matheus de Souza Gomes
- Institute of Genetics and Biochemistry (INGEB),Laboratory of Bioinformatics and Molecular Analysis (LBAM), Federal University of Uberlândia (UFU)- Campus Patos de Minas, Patos de Minas, Minas Gerais, Brasil
| | - Antonio Chalfun-Junior
- Department of Biology, Section of Plant Physiology, Laboratory of Plant Molecular Physiology (LFMP), Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil
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Abstract
The eukaryotic genomes are pervasively transcribed. In addition to protein-coding RNAs, thousands of long noncoding RNAs (lncRNAs) modulate key molecular and biological processes. Most lncRNAs are found in the nucleus and associate with chromatin, but lncRNAs can function in both nuclear and cytoplasmic compartments. Emerging work has found that many lncRNAs regulate gene expression and can affect genome stability and nuclear domain organization both in plant and in the animal kingdom. Here, we describe the major plant lncRNAs and how they act, with a focus on research in Arabidopsis thaliana and our emerging understanding of lncRNA functions in serving as molecular sponges and decoys, functioning in regulation of transcription and silencing, particularly in RNA-directed DNA methylation, and in epigenetic regulation of flowering time.
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Affiliation(s)
- Hsiao-Lin V Wang
- School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO, 64110, USA
| | - Julia A Chekanova
- School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO, 64110, USA.
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43
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Liu L, Yan X, Kong X, Zhao Y, Gong Z, Jin JB, Guo Y. Transcriptional Gene Silencing Maintained by OTS1 SUMO Protease Requires a DNA-Dependent Polymerase V-Dependent Pathway. PLANT PHYSIOLOGY 2017; 173:655-667. [PMID: 27852949 PMCID: PMC5210737 DOI: 10.1104/pp.16.01365] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/14/2016] [Indexed: 05/21/2023]
Abstract
The expression of genes with aberrant structure is prevented at both the transcriptional and posttranscriptional regulation levels. Aberrant gene silencing at the posttranscriptional level is well studied; however, it is not well understood how aberrant genes are silenced at the transcriptional level. In this study, through genetic screening a transgenic report line that harbors an aberrant gene (35S-LUC, lacking 3'-untranslated region [3'-UTR]) and lacks luciferase (LUC) activity, we identify that the small ubiquitin-like modifier (SUMO) protease OTS1 gene is required for maintaining the silence of the reporter 35S-LUC and an endogenous mutator-like element MULE-F19G14 at the transcriptional level, which requires DNA-dependent RNA polymerase (Pol) V and DDR complex, but not Pol IV. The increased transcripts in ots1 mutants are terminated by the 3'-UTRs of downstream genes. In addition to ots1 mutations, mutations in several known or putative SUMO proteases and two SUMO E3 ligases, SIZ1 and MMS21, have similar effects on this silencing regulation. Taken together, our results reveal that the enzymes involved in the SUMOylation process restrain aberrant gene transcription by using a downstream gene 3'-UTR, and this regulation requires a functional Pol V-dependent pathway in Arabidopsis (Arabidopsis thaliana).
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Affiliation(s)
- Lei Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
| | - Xiaojing Yan
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
| | - Xiangxiong Kong
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
| | - Yiqiang Zhao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
| | - Zhizhong Gong
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
| | - Jing Bo Jin
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
| | - Yan Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China (L.L., X.Y., Y.Z., Z.G., Y.G.); and
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China (X.K., J.B.J.)
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Abstract
Plants must adapt to multiple biotic and abiotic stresses ; thus, sensing and responding to environmental signals is imperative for their survival. Moreover, understanding these responses is imperative for efforts to improve plant yield and consistency. Regulation of transcript levels is a key aspect of the plant response to environmental signals. Long noncoding RNAs (lncRNAs) have gained widespread attention in recent years with the advance of high-throughput sequencing technologies. As important biological regulators, lncRNAs have been implicated in a wide range of developmental processes and diseases in animals. However, knowledge of the role that lncRNAs play in plant stress tolerance remains limited. Here, we review recent studies on the identification, characteristics, classification, and biological functions of lncRNAs in response to various stresses, including bacterial pathogens, excess light, drought, salinity, hypoxia, extreme temperatures, and nitrogen/phosphate deficiency. We also discuss possible directions for future research.
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45
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Lebedeva MA, Tvorogova VE, Tikhodeyev ON. Epigenetic mechanisms and their role in plant development. RUSS J GENET+ 2016. [DOI: 10.1134/s1022795417090083] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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46
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Gouil Q, Baulcombe DC. DNA Methylation Signatures of the Plant Chromomethyltransferases. PLoS Genet 2016; 12:e1006526. [PMID: 27997534 PMCID: PMC5221884 DOI: 10.1371/journal.pgen.1006526] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/09/2017] [Accepted: 12/07/2016] [Indexed: 12/22/2022] Open
Abstract
DNA methylation in plants is traditionally partitioned into CG, CHG and CHH contexts (with H any nucleotide but G). By investigating DNA methylation patterns in trinucleotide contexts in four angiosperm species, we show that such a representation hides spatial and functional partitioning of different methylation pathways and is incomplete. CG methylation (mCG) is largely context-independent whereas, at CHG motifs, there is under-representation of mCCG in pericentric regions of A. thaliana and tomato and throughout the chromosomes of maize and rice. In A. thaliana the biased representation of mCCG in heterochromatin is related to specificities of H3K9 methyltransferase SUVH family members. At CHH motifs there is an over-representation of different variant forms of mCHH that, similarly to mCCG hypomethylation, is partitioned into the pericentric regions of the two dicots but dispersed in the monocot chromosomes. The over-represented mCHH motifs in A. thaliana associate with specific types of transposon including both class I and II elements. At mCHH the contextual bias is due to the involvement of various chromomethyltransferases whereas the context-independent CHH methylation in A. thaliana and tomato is mediated by the RNA-directed DNA methylation process that is most active in the gene-rich euchromatin. This analysis therefore reveals that the sequence context of the methylome of plant genomes is informative about the mechanisms associated with maintenance of methylation and the overlying chromatin structure. Dense cytosine DNA methylation (mC) in eukaryotes is associated with closed chromatin and gene silencing. In plants it is well known that the sequence context of the mC (either mCG, mCHG or mCHH) provides a clue as to which of several mechanisms is involved but now, based on detailed analyses of the DNA methylome in wild type and mutants of four plant species, we reveal that there is additional information in the mC sequence context. Low mCCG and over-representation of mCAA and mCTA or mCAT in A. thaliana and tomato differentiates regions of the chromosomes near the centromere where methylation is dominated by chromomethyltransferases from the chromosome arms in which mCHH is context-independent and predominantly RNA-directed. Rice and maize have similar sequence context-dependent DNA methylation but the corresponding chromosome domains are not spatially separate as in the dicots. The discovery of the subcomponents of plant methylomes based on sequence context will allow greater resolution in past and future analyses of plant methylomes.
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Affiliation(s)
- Quentin Gouil
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - David C. Baulcombe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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47
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Lahmy S, Pontier D, Bies-Etheve N, Laudié M, Feng S, Jobet E, Hale CJ, Cooke R, Hakimi MA, Angelov D, Jacobsen SE, Lagrange T. Evidence for ARGONAUTE4-DNA interactions in RNA-directed DNA methylation in plants. Genes Dev 2016; 30:2565-2570. [PMID: 27986858 PMCID: PMC5204349 DOI: 10.1101/gad.289553.116] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/17/2016] [Indexed: 12/29/2022]
Abstract
RNA polymerase V (Pol V) long noncoding RNAs (lncRNAs) have been proposed to guide ARGONAUTE4 (AGO4) to chromatin in RNA-directed DNA methylation (RdDM) in plants. Here, we provide evidence, based on laser UV-assisted zero-length cross-linking, for functionally relevant AGO4-DNA interaction at RdDM targets. We further demonstrate that Pol V lncRNAs or the act of their transcription are required to lock Pol V holoenzyme into a stable DNA-bound state that allows AGO4 recruitment via redundant glycine-tryptophan/tryptophan-glycine AGO hook motifs present on both Pol V and its associated factor, SPT5L. We propose a model in which AGO4-DNA interaction could be responsible for the unique specificities of RdDM.
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Affiliation(s)
- Sylvie Lahmy
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
| | - Dominique Pontier
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
| | - Natacha Bies-Etheve
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
| | - Michèle Laudié
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
| | - Suhua Feng
- Department of Molecular, Cell, and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA.,Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Edouard Jobet
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
| | - Christopher J Hale
- Department of Molecular, Cell, and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA.,Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California at Los Angeles, Los Angeles, California 90095, USA.,Department of Pathology, Center for Precision Diagnostics, University of Washington, Seattle, Washington 98195, USA
| | - Richard Cooke
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
| | - Mohamed-Ali Hakimi
- Institute for Advanced Biosciences (IAB), UMR5309, CNRS, U1209, Institut National de la Santé et de la Recherche Médicale (INSERM), Grenoble Alpes University, 38000 Grenoble, France
| | - Dimitar Angelov
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC), UMR 5239, CNRS/École Normale Supérieure de Lyon (ENSL)/Université Claude Bernard Lyon 1 (UCBL), 69007 Lyon, France.,Institut NeuroMyogène (INMG), UMR 5310, CNRS/UCBL/ENSL, 69007 Lyon, France
| | - Steven E Jacobsen
- Department of Molecular, Cell, and Developmental Biology, University of California at Los Angeles, Los Angeles, California 90095, USA.,Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California at Los Angeles, Los Angeles, California 90095, USA.,Howard Hughes Medical Institute, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Thierry Lagrange
- Laboratoire Génome et Développement des Plantes (LGDP), UMR5096, Centre National de la Recherche Scientifique (CNRS), Université de Perpignan via Domitia (UPVD), 66860 Perpignan, France
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Böhmdorfer G, Sethuraman S, Rowley MJ, Krzyszton M, Rothi MH, Bouzit L, Wierzbicki AT. Long non-coding RNA produced by RNA polymerase V determines boundaries of heterochromatin. eLife 2016; 5. [PMID: 27779094 PMCID: PMC5079748 DOI: 10.7554/elife.19092] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 10/06/2016] [Indexed: 01/10/2023] Open
Abstract
RNA-mediated transcriptional gene silencing is a conserved process where small RNAs target transposons and other sequences for repression by establishing chromatin modifications. A central element of this process are long non-coding RNAs (lncRNA), which in Arabidopsis thaliana are produced by a specialized RNA polymerase known as Pol V. Here we show that non-coding transcription by Pol V is controlled by preexisting chromatin modifications located within the transcribed regions. Most Pol V transcripts are associated with AGO4 but are not sliced by AGO4. Pol V-dependent DNA methylation is established on both strands of DNA and is tightly restricted to Pol V-transcribed regions. This indicates that chromatin modifications are established in close proximity to Pol V. Finally, Pol V transcription is preferentially enriched on edges of silenced transposable elements, where Pol V transcribes into TEs. We propose that Pol V may play an important role in the determination of heterochromatin boundaries. DOI:http://dx.doi.org/10.7554/eLife.19092.001
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Affiliation(s)
- Gudrun Böhmdorfer
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Shriya Sethuraman
- Bioinformatics Graduate Program, University of Michigan, Ann Arbor, United States
| | - M Jordan Rowley
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Michal Krzyszton
- Faculty of Biology, Institute of Genetics and Biotechnology, University of Warsaw, Warsaw, Poland
| | - M Hafiz Rothi
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Lilia Bouzit
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Andrzej T Wierzbicki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
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Wendte JM, Pikaard CS. The RNAs of RNA-directed DNA methylation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1860:140-148. [PMID: 27521981 DOI: 10.1016/j.bbagrm.2016.08.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/05/2016] [Accepted: 08/06/2016] [Indexed: 10/21/2022]
Abstract
RNA-directed chromatin modification that includes cytosine methylation silences transposable elements in both plants and mammals, contributing to genome defense and stability. In Arabidopsis thaliana, most RNA-directed DNA methylation (RdDM) is guided by small RNAs derived from double-stranded precursors synthesized at cytosine-methylated loci by nuclear multisubunit RNA Polymerase IV (Pol IV), in close partnership with the RNA-dependent RNA polymerase, RDR2. These small RNAs help keep transposons transcriptionally inactive. However, if transposons escape silencing, and are transcribed by multisubunit RNA polymerase II (Pol II), their mRNAs can be recognized and degraded, generating small RNAs that can also guide initial DNA methylation, thereby enabling subsequent Pol IV-RDR2 recruitment. In both pathways, the small RNAs find their target sites by interacting with longer noncoding RNAs synthesized by multisubunit RNA Polymerase V (Pol V). Despite a decade of progress, numerous questions remain concerning the initiation, synthesis, processing, size and features of the RNAs that drive RdDM. Here, we review recent insights, questions and controversies concerning RNAs produced by Pols IV and V, and their functions in RdDM. We also provide new data concerning Pol V transcript 5' and 3' ends. This article is part of a Special Issue entitled: Plant Gene Regulatory Mechanisms and Networks. This article is part of a Special Issue entitled: Plant Gene Regulatory Mechanisms and Networks, edited by Dr. Erich Grotewold and Dr. Nathan Springer.
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Affiliation(s)
- Jered M Wendte
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA
| | - Craig S Pikaard
- Department of Biology and Department of Molecular and Cellular Biochemistry, Indiana University, 915 E. Third Street, Bloomington, IN 47405, USA; Howard Hughes Medical Institute, Indiana University, Bloomington, IN 47405, USA.
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Dalakouras A, Dadami E, Wassenegger M, Krczal G, Wassenegger M. RNA-directed DNA methylation efficiency depends on trigger and target sequence identity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:202-14. [PMID: 27121647 DOI: 10.1111/tpj.13193] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 04/06/2016] [Accepted: 04/06/2016] [Indexed: 06/05/2023]
Abstract
RNA-directed DNA methylation (RdDM) in plants has been extensively studied, but the RNA molecules guiding the RdDM machinery to their targets are still to be characterized. It is unclear whether these molecules require full complementarity with their target. In this study, we have generated Nicotiana tabacum (Nt) plants carrying an infectious tomato apical stunt viroid (TASVd) transgene (Nt-TASVd) and a non-infectious potato spindle tuber viroid (PSTVd) transgene (Nt-SB2). The two viroid sequences exhibit 81% sequence identity. Nt-TASVd and Nt-SB2 plants were genetically crossed. In the progeny plants (Nt-SB2/TASVd), deep sequencing of small RNAs (sRNAs) showed that TASVd infection was associated with the accumulation of abundant small interfering RNAs (siRNAs) that mapped along the entire TASVd but only partially matched the SB2 transgene. TASVd siRNAs efficiently targeted SB2 RNA for degradation, but no transitivity was detectable. Bisulfite sequencing in the Nt-SB2/TASVd plants revealed that the TASVd transgene was targeted for dense cis-RdDM along its entire sequence. In the same plants, the SB2 transgene was targeted for trans-RdDM. The SB2 methylation pattern, however, was weak and heterogeneous, pointing to a positive correlation between trigger-target sequence identity and RdDM efficiency. Importantly, trans-RdDM on SB2 was also detected at sites where no homologous siRNAs were detected. Our data indicate that RdDM efficiency depends on the trigger-target sequence identity, and is not restricted to siRNA occupancy. These findings support recent data suggesting that RNAs with sizes longer than 24 nt (>24-nt RNAs) trigger RdDM.
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Affiliation(s)
- Athanasios Dalakouras
- RLP AgroScience GmbH, AlPlanta-Institute for Plant Research, Neustadt, 67435, Germany
| | - Elena Dadami
- RLP AgroScience GmbH, AlPlanta-Institute for Plant Research, Neustadt, 67435, Germany
| | - Michèle Wassenegger
- RLP AgroScience GmbH, AlPlanta-Institute for Plant Research, Neustadt, 67435, Germany
| | - Gabi Krczal
- RLP AgroScience GmbH, AlPlanta-Institute for Plant Research, Neustadt, 67435, Germany
| | - Michael Wassenegger
- RLP AgroScience GmbH, AlPlanta-Institute for Plant Research, Neustadt, 67435, Germany
- Centre for Organismal Studies (COS) Heidelberg, University of Heidelberg, Heidelberg, 69120, Germany
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