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Han X, Wang J, Zhang Y, Kong Y, Dong H, Feng X, Li T, Zhou C, Yu J, Xin D, Chen Q, Qi Z. Changes in the m6A RNA methylome accompany the promotion of soybean root growth by rhizobia under cadmium stress. JOURNAL OF HAZARDOUS MATERIALS 2023; 441:129843. [PMID: 36113351 DOI: 10.1016/j.jhazmat.2022.129843] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/13/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Cadmium (Cd) is the most widely distributed heavy metal pollutant in soil and has significant negative effects on crop yields and human health. Rhizobia can enhance soybean growth in the presence of heavy metals, and the legume-rhizobia symbiosis has been used to promote heavy-metal phytoremediation, but much remains to be learned about the molecular networks that underlie these effects. Here, we demonstrated that soybean root growth was strongly suppressed after seven days of Cd exposure but that the presence of rhizobia largely eliminated this effect, even prior to nodule development. Moreover, rhizobia did not appear to promote root growth by limiting plant Cd uptake: seedlings with and without rhizobia had similar root Cd concentrations. Previous studies have demonstrated a role for m6A RNA methylation in the response of rice and barley to Cd stress. We therefore performed transcriptome-wide m6A methylation profiling to investigate changes in the soybean RNA methylome in response to Cd with and without rhizobia. Here, we provide some of the first data on transcriptome-wide m6a RNA methylation patterns in soybean; m6A modifications were concentrated at the 3' UTR of transcripts and showed a positive relationship with transcript abundance. Transcriptome-wide m6A RNA methylation peaks increased in the presence of Cd, and the integration of m6A methylome and transcriptome results enabled us to identify 154 genes whose transcripts were both differentially methylated and differentially expressed in response to Cd stress. Annotation results suggested that these genes were associated with Ca2+ homeostasis, ROS pathways, polyamine metabolism, MAPK signaling, hormones, and biotic stress responses. There were 176 differentially methylated and expressed transcripts under Cd stress in the presence of rhizobia. In contrast to the Cd-only gene set, they were also enriched in genes related to auxin, jasmonic acid, and brassinosteroids, as well as abiotic stress tolerance. They contained fewer genes related to Ca2+ homeostasis and also included candidates with known functions in the legume-rhizobia symbiosis. These findings offer new insights into how rhizobia promote soybean root growth under Cd stress; they provide candidate genes for research on plant heavy metal responses and for the use of legumes in phytoremediation.
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Affiliation(s)
- Xue Han
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Jialin Wang
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Yu Zhang
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Youlin Kong
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Huiying Dong
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Xuezhen Feng
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Tianshu Li
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Changjun Zhou
- Daqing Branch, Heilongjiang Academy of Agricultural Sciences, Daqing 163316, Heilongjiang, People's Republic of China
| | - Jidong Yu
- Daqing Branch, Heilongjiang Academy of Agricultural Sciences, Daqing 163316, Heilongjiang, People's Republic of China
| | - Dawei Xin
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China
| | - Qingshan Chen
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China.
| | - Zhaoming Qi
- College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China.
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Bhatia G, Prall W, Sharma B, Gregory BD. Covalent RNA modifications and their budding crosstalk with plant epigenetic processes. CURRENT OPINION IN PLANT BIOLOGY 2022; 69:102287. [PMID: 35988352 DOI: 10.1016/j.pbi.2022.102287] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/29/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Our recent cognizance of diverse RNA classes undergoing dynamic covalent chemical modifications (or epitranscriptomic marks) in plants has provided fresh insight into the underlying molecular mechanisms of gene expression regulation. Comparatively, epigenetic marks comprising heritable modifications of DNA and histones have been extensively studied in plants and their impact on plant gene expression is quite established. Based on our growing knowledge of the plant epitranscriptome and epigenome, it is logical to explore how the two regulatory layers intermingle to intricately determine gene expression levels underlying key biological processes such as development and response to stress. Herein, we focus on the emerging evidence of crosstalk between the plant epitranscriptome with epigenetic regulation involving DNA modification, histone modification, and non-coding RNAs.
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Affiliation(s)
- Garima Bhatia
- Department of Biology, University of Pennsylvania, School of Arts and Sciences, Philadelphia, PA 19104, USA
| | - Wil Prall
- Department of Biology, University of Pennsylvania, School of Arts and Sciences, Philadelphia, PA 19104, USA
| | - Bishwas Sharma
- Department of Biology, University of Pennsylvania, School of Arts and Sciences, Philadelphia, PA 19104, USA
| | - Brian D Gregory
- Department of Biology, University of Pennsylvania, School of Arts and Sciences, Philadelphia, PA 19104, USA.
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Ramakrishnan M, Rajan KS, Mullasseri S, Palakkal S, Kalpana K, Sharma A, Zhou M, Vinod KK, Ramasamy S, Wei Q. The plant epitranscriptome: revisiting pseudouridine and 2'-O-methyl RNA modifications. PLANT BIOTECHNOLOGY JOURNAL 2022; 20:1241-1256. [PMID: 35445501 PMCID: PMC9241379 DOI: 10.1111/pbi.13829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/11/2022] [Accepted: 04/18/2022] [Indexed: 06/01/2023]
Abstract
There is growing evidence that post-transcriptional RNA modifications are highly dynamic and can be used to improve crop production. Although more than 172 unique types of RNA modifications have been identified throughout the kingdom of life, we are yet to leverage upon the understanding to optimize RNA modifications in crops to improve productivity. The contributions of internal mRNA modifications such as N6-methyladenosine (m6 A) and 5-methylcytosine (m5 C) methylations to embryonic development, root development, leaf morphogenesis, flowering, fruit ripening and stress response are sufficiently known, but the roles of the two most abundant RNA modifications, pseudouridine (Ψ) and 2'-O-methylation (Nm), in the cell remain unclear due to insufficient advances in high-throughput technologies in plant development. Therefore, in this review, we discuss the latest methods and insights gained in mapping internal Ψ and Nm and their unique properties in plants and other organisms. In addition, we discuss the limitations that remain in high-throughput technologies for qualitative and quantitative mapping of these RNA modifications and highlight future challenges in regulating the plant epitranscriptome.
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Affiliation(s)
- Muthusamy Ramakrishnan
- Co‐Innovation Center for Sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjingJiangsuChina
- Bamboo Research InstituteNanjing Forestry UniversityNanjingJiangsuChina
| | - K. Shanmugha Rajan
- The Mina and Everard Goodman Faculty of Life Sciences and Advanced Materials and Nanotechnology InstituteBar‐Ilan University52900Ramat‐GanIsrael
- Department of Chemical and Structural BiologyWeizmann Institute7610001RehovotIsrael
| | - Sileesh Mullasseri
- School of Ocean Science and TechnologyKerala University of Fisheries and Ocean StudiesCochinIndia
| | - Sarin Palakkal
- The Institute for Drug ResearchSchool of PharmacyThe Hebrew University of JerusalemJerusalemIsrael
| | - Krishnan Kalpana
- Department of Plant PathologyAgricultural College and Research InstituteTamilnadu Agricultural University625 104MaduraiTamil NaduIndia
| | - Anket Sharma
- State Key Laboratory of Subtropical SilvicultureZhejiang A&F UniversityHangzhouZhejiangChina
| | - Mingbing Zhou
- State Key Laboratory of Subtropical SilvicultureZhejiang A&F UniversityHangzhouZhejiangChina
- Zhejiang Provincial Collaborative Innovation Center for Bamboo Resources and High‐Efficiency UtilizationZhejiang A&F UniversityHangzhouZhejiangChina
| | | | - Subbiah Ramasamy
- Cardiac Metabolic Disease LaboratoryDepartment of BiochemistrySchool of Biological SciencesMadurai Kamaraj UniversityMaduraiTamil NaduIndia
| | - Qiang Wei
- Co‐Innovation Center for Sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjingJiangsuChina
- Bamboo Research InstituteNanjing Forestry UniversityNanjingJiangsuChina
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4
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Han J, Kong H, Wang X, Zhang XA. Novel insights into the interaction between N6-methyladenosine methylation and noncoding RNAs in musculoskeletal disorders. Cell Prolif 2022; 55:e13294. [PMID: 35735243 PMCID: PMC9528765 DOI: 10.1111/cpr.13294] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/31/2022] [Accepted: 06/07/2022] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Musculoskeletal disorder (MSD) are a class of inflammatory and degener-ative diseases, but the precise molecular mechanisms are still poorly understood. Noncoding RNA (ncRNA) N6-methyladenosine (m6A) modification plays an essential role in the pathophysiological process of MSD. This review summarized the interaction be-tween m6A RNA methylation and ncRNAs in the molecular regulatory mechanism of MSD. It provides a new perspective for the pathophysiological mechanism and ncRNA m6A targeted therapy of MSD. METHODS A comprehensive search of databases was conducted with musculoskeletal disorders, noncoding RNA, N6-methyladenosine, intervertebral disc degeneration, oste-oporosis, osteosarcoma, osteoarthritis, skeletal muscle, bone, and cartilage as the key-words. Then, summarized all the relevant articles. RESULTS Intervertebral disc degeneration (IDD), osteoporosis (OP), osteosarcoma (OS), and osteoarthritis (OA) are common MSDs that affect muscle, bone, cartilage, and joint, leading to limited movement, pain, and disability. However, the precise pathogenesis remains unclear, and no effective treatment and drug is available at present. Numerous studies confirmed that the mutual regulation between m6A and ncRNAs (i.e., microRNAs, long ncRNAs, and circular RNAs) was found in MSD, m6A modification can regulate ncRNAs, and ncRNAs can also target m6A regulators. ncRNA m6A modification plays an essential role in the pathophysiological process of MSDs by regulating the homeostasis of skeletal muscle, bone, and cartilage. CONCLUSION m6A interacts with ncRNAs to regulate multiple biological processes and plays important roles in IDD, OP, OS, and OA. These studies provide new insights into the pathophysiological mechanism of MSD and targeting m6A-modified ncRNAs may be a promising therapy approach.
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Affiliation(s)
- Juanjuan Han
- College of Kinesiology, Shenyang Sport University, Shenyang, China.,Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
| | - Hui Kong
- College of Kinesiology, Shenyang Sport University, Shenyang, China
| | - Xueqiang Wang
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China.,Department of Rehabilitation Medicine, Shanghai Shangti Orthopaedic Hospital, Shanghai, China
| | - Xin-An Zhang
- College of Kinesiology, Shenyang Sport University, Shenyang, China
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Sun X, Wu W, Yang Y, Wilson I, Shao F, Qiu D. Genome-Wide Identification of m6A Writers, Erasers and Readers in Poplar 84K. Genes (Basel) 2022; 13:genes13061018. [PMID: 35741780 PMCID: PMC9223284 DOI: 10.3390/genes13061018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/28/2022] [Accepted: 05/31/2022] [Indexed: 11/16/2022] Open
Abstract
N6-methyladenosine (m6A) RNA modification is a conserved mechanism to regulate gene expression that plays vital roles in the development of plants. However, the m6A RNA modification in forest trees remains limited. Here, we performed a complete analysis of m6A writers, erasers and readers in Poplar 84K, including gene location, gene structures, conserved motifs, phylogenetic relationships, promoter analysis, expression profiles and the homology modeling. We have identified 61 m6A pathway genes in Poplar 84K (Populus alba × Populus glandulosa), including 14 m6A writers, 14 m6A erasers and 33 m6A readers. Phylogenetic analysis indicated that the m6A writers and erasers were clustered into four groups and m6A readers were clustered into two groups. Promoter analysis showed that m6A pathway genes were mainly responsive to low oxygen followed by ABA and ethylene. The expression of the identified m6A pathway genes showed tissue-specific expression patterns in leaves, xylem, phloem and roots. Moreover, 17 genes were significantly up-regulated and 13 genes were significantly down-regulated in poplar overexpressing the transcription factor LBD15. Homology modeling and molecular docking results suggested that PagFIP37b was most likely to be regulated by LBD15, and the qPCRshowed that PagFIP37b were up-regulated in the LBD15-oe plants. The results provide insights that aid in the future elucidation of the functions of these m6A pathway genes and the epigenetic regulation mechanism of these genes in Poplar 84K.
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Affiliation(s)
- Xiaochen Sun
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China; (X.S.); (W.W.); (Y.Y.); (D.Q.)
| | - Wenli Wu
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China; (X.S.); (W.W.); (Y.Y.); (D.Q.)
| | - Yanfang Yang
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China; (X.S.); (W.W.); (Y.Y.); (D.Q.)
| | - Iain Wilson
- CSIRO Agriculture and Food, Canberra, ACT 2601, Australia;
| | - Fenjuan Shao
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China; (X.S.); (W.W.); (Y.Y.); (D.Q.)
- Correspondence: ; Tel.: +86-10-62889641; Fax: +86-10-62872015
| | - Deyou Qiu
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China; (X.S.); (W.W.); (Y.Y.); (D.Q.)
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6
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Cai T, Atteh LL, Zhang X, Huang C, Bai M, Ma H, Zhang C, Fu W, Gao L, Lin Y, Meng W. The N6-Methyladenosine Modification and Its Role in mRNA Metabolism and Gastrointestinal Tract Disease. Front Surg 2022; 9:819335. [PMID: 35155557 PMCID: PMC8831730 DOI: 10.3389/fsurg.2022.819335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 01/10/2022] [Indexed: 11/13/2022] Open
Abstract
The N6-methyladenosine (m6A) modification is the most abundant internal modification of messenger RNA (mRNA) in higher eukaryotes. Under the actions of methyltransferase, demethylase and methyl-binding protein, m6A resulting from RNA methylation becomes dynamic and reversible, similar to that from DNA methylation, and this effect allows the generated mRNA to participate in metabolism processes, such as splicing, transport, translation, and degradation. The most common tumors are those found in the gastrointestinal tract, and research on these tumors has flourished since the discovery of m6A. Overall, further analysis of the mechanism of m6A and its role in tumors may contribute to new ideas for the treatment of tumors. m6A also plays an important role in non-tumor diseases of the gastrointestinal tract. This manuscript reviews the current knowledge of m6A-related proteins, mRNA metabolism and their application in gastrointestinal tract disease.
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Affiliation(s)
- Teng Cai
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
- Gansu Province Key Laboratory Biotherapy and Regenerative Medicine, Lanzhou, China
| | | | - Xianzhuo Zhang
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Chongfei Huang
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Mingzhen Bai
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Haidong Ma
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Chao Zhang
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Wenkang Fu
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Long Gao
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
| | - Yanyan Lin
- The Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, China
- Gansu Province Institute of Hepatopancreatobiliary Surgery, Lanzhou, China
- Yanyan Lin
| | - Wenbo Meng
- The First Clinical Medical College, Lanzhou University, Lanzhou, China
- The Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, China
- Gansu Province Institute of Hepatopancreatobiliary Surgery, Lanzhou, China
- *Correspondence: Wenbo Meng
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Mao X, Hou N, Liu Z, He J. Profiling of N 6-Methyladenosine (m 6A) Modification Landscape in Response to Drought Stress in Apple ( Malus prunifolia (Willd.) Borkh). PLANTS (BASEL, SWITZERLAND) 2021; 11:plants11010103. [PMID: 35009106 PMCID: PMC8747461 DOI: 10.3390/plants11010103] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/15/2021] [Accepted: 12/20/2021] [Indexed: 05/26/2023]
Abstract
Drought stress is a significant environmental factor limiting crop growth worldwide. Malus prunifolia is an important apple species endemic to China and is used for apple cultivars and rootstocks with great drought tolerance. N6-methyladenosine (m6A) is a common epigenetic modification on messenger RNAs (mRNAs) in eukaryotes which is critical for various biological processes. However, there are no reports on m6A methylation in apple response to drought stress. Here, we assessed the m6A landscape of M. prunifolia seedlings in response to drought and analyzed the association between m6A modification and transcript expression. In total, we found 19,783 and 19,609 significant m6A peaks in the control and drought treatment groups, respectively, and discovered a UGUAH (H: A/U/C) motif. In M. prunifolia, under both control and drought conditions, peaks were highly enriched in the 3' untranslated region (UTR) and coding sequence (CDS). Among 4204 significant differential m6A peaks in drought-treated M. prunifolia compared to control-treated M. prunifolia, 4158 genes with m6A modification were identified. Interestingly, a large number of hypermethylated peaks (4069) were stimulated by drought treatment compared to hypomethylation. Among the hypermethylated peak-related genes, 972 and 1238 differentially expressed genes (DEGs) were up- and down-regulated in response to drought, respectively. Gene ontology (GO) analyses of differential m6A-modified genes revealed that GO slims related to RNA processing, epigenetic regulation, and stress tolerance were significantly enriched. The m6A modification landscape depicted in this study sheds light on the epigenetic regulation of M. prunifolia in response to drought stress and indicates new directions for the breeding of drought-tolerant apple trees.
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Affiliation(s)
- Xiushan Mao
- Shandong Transport Vocational College, 7369 Bohai Road, Weifang 261206, China;
| | - Nan Hou
- State Key Laboratory of Crop Stress Biology for Arid Areas, Yangling, Xianyang 712100, China;
- Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
| | - Zhenzhong Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, Yangling, Xianyang 712100, China;
- Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
| | - Jieqiang He
- State Key Laboratory of Crop Stress Biology for Arid Areas, Yangling, Xianyang 712100, China;
- Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Xianyang 712100, China
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Structure and Sequence Requirements for RNA Capping at the Venezuelan Equine Encephalitis Virus RNA 5' End. J Virol 2021; 95:e0077721. [PMID: 34011549 DOI: 10.1128/jvi.00777-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Venezuelan equine encephalitis virus (VEEV) is a reemerging arthropod-borne virus causing encephalitis in humans and domesticated animals. VEEV possesses a positive single-stranded RNA genome capped at its 5' end. The capping process is performed by the nonstructural protein nsP1, which bears methyl and guanylyltransferase activities. The capping reaction starts with the methylation of GTP. The generated m7GTP is complexed to the enzyme to form an m7GMP-nsP1 covalent intermediate. The m7GMP is then transferred onto the 5'-diphosphate end of the viral RNA. Here, we explore the specificities of the acceptor substrate in terms of length, RNA secondary structure, and/or sequence. Any diphosphate nucleosides but GDP can serve as acceptors of the m7GMP to yield m7GpppA, m7GpppC, or m7GpppU. We show that capping is more efficient on small RNA molecules, whereas RNAs longer than 130 nucleotides are barely capped by the enzyme. The structure and sequence of the short, conserved stem-loop, downstream to the cap, is an essential regulatory element for the capping process. IMPORTANCE The emergence, reemergence, and expansion of alphaviruses (genus of the family Togaviridae) are a serious public health and epizootic threat. Venezuelan equine encephalitis virus (VEEV) causes encephalitis in human and domesticated animals, with a mortality rate reaching 80% in horses. To date, no efficient vaccine or safe antivirals are available for human use. VEEV nonstructural protein 1 (nsP1) is the viral capping enzyme characteristic of the Alphavirus genus. nsP1 catalyzes methyltransferase and guanylyltransferase reactions, representing a good therapeutic target. In the present report, we provide insights into the molecular features and specificities of the cap acceptor substrate for the guanylylation reaction.
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Zhu W, Wang JZ, Wei JF, Lu C. Role of m6A methyltransferase component VIRMA in multiple human cancers (Review). Cancer Cell Int 2021; 21:172. [PMID: 33731118 PMCID: PMC7968318 DOI: 10.1186/s12935-021-01868-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/06/2021] [Indexed: 12/18/2022] Open
Abstract
N6-Methyladenosine (m6A) modification is one of the most widely distributed RNA modifications in eukaryotes. It participates in various RNA functions and plays vital roles in tissue development, stem cell formation and differentiation, heat shock response control, and circadian clock controlling, particularly during tumor development. The reversible regulation of m6A modification is affected by the so-called ‘reader’, ‘writer’ and ‘eraser’. As a required component and the largest methyltransferase, vir-like m6A methyltransferase associated (VIRMA) can promote the progression of cancer and is associated with poor survival in multiple types of cancer. The present review investigated the role of VIRMA in various types of cancer. In an m6A-dependent or -independent manner, VIRMA can play an oncogenic role by regulating cancer cell proliferation, migration and invasion, metastasis, apoptosis resistance and tumor growth in different pathways by targeting stem factors, CCAT1/2, ID2, GATA3, CDK1, c-Jun, etc. VIRMA can also predict better prognosis in kidney renal clear cell carcinoma (KIRC), kidney renal papillary cell carcinoma (KIRP) and papillary thyroid carcinoma by TCGA analysis. The obvious oncogenic roles of VIRMA observed in different types of cancer and the mechanisms of VIRMA promoting cancers provided the basis for potential therapeutic targeting for cancer treatments.
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Affiliation(s)
- Wei Zhu
- Precision Medicine Center, First Affiliated Hospital of Gannan Medical University, 128 Jinling Road, Ganzhou, 341000, China.,Research Division of Clinical Pharmacology, The First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital), 300 Guangzhou Road, Nanjing, 210029, Jiangsu, China
| | - Jing-Zi Wang
- Department of Urology, Children's Hospital of Nanjing Medical University, 72 Guangzhou Road, Nanjing, 210029, Jiangsu, China
| | - Ji-Fu Wei
- Precision Medicine Center, First Affiliated Hospital of Gannan Medical University, 128 Jinling Road, Ganzhou, 341000, China. .,Research Division of Clinical Pharmacology, The First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital), 300 Guangzhou Road, Nanjing, 210029, Jiangsu, China.
| | - Chen Lu
- Precision Medicine Center, First Affiliated Hospital of Gannan Medical University, 128 Jinling Road, Ganzhou, 341000, China.
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10
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Scarrow M, Chen N, Sun G. Insights into the N 6-methyladenosine mechanism and its functionality: progress and questions. Crit Rev Biotechnol 2020; 40:639-652. [PMID: 32321323 DOI: 10.1080/07388551.2020.1751059] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
N6-methyladenosine (m6A) RNA methylation has become a progressively popular area of molecular research since the discovery of its potentially essential regulatory role amongst eukaryotes. m6A marks are observed in the 5'UTR, 3'UTR and coding regions of eukaryotes and its mediation has been associated with various human diseases, RNA stability and translational efficiency. To understand the implications of m6A methylation in molecular governance, its functionality and mechanism must be initially understood. m6A regulation through its readers, writers and erasers as well as an insight into the potential "cross-talk" occurring between m6A and previously well documented regulatory molecular mechanisms have been characterized. The majority of research to date has been limited to few species and has yet to explore the species- and tissue specific nature or mechanistic plasticity of m6A regulation. There is still a tremendous gap in our knowledge surrounding the mechanism and functionality of m6A RNA methylation. Here we review the formation, removal, and decoding of m6A amongst animals, yeast, and plants while noting potential "cross-talk" between various mechanisms and highlighting potential areas of future research.
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Affiliation(s)
| | - Ning Chen
- Biology Department, Saint Mary's University, Halifax, Canada
| | - Genlou Sun
- Biology Department, Saint Mary's University, Halifax, Canada
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11
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MTA, an RNA m 6A Methyltransferase, Enhances Drought Tolerance by Regulating the Development of Trichomes and Roots in Poplar. Int J Mol Sci 2020; 21:ijms21072462. [PMID: 32252292 PMCID: PMC7177244 DOI: 10.3390/ijms21072462] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 03/26/2020] [Accepted: 03/31/2020] [Indexed: 11/17/2022] Open
Abstract
N6-methyladenosine (m6A) is the most prevalent internal modification present in the mRNAs of all higher eukaryotes, where it is present within both coding and noncoding regions. In mammals, methylation requires the catalysis of a multicomponent m6A methyltransferase complex. Proposed biological functions for m6A modification include pre-mRNA splicing, RNA stability, cell fate regulation, and embryonic development. However, few studies have been conducted on m6A modification in trees. In particular, the regulation mechanism of RNA m6A in Populus development remains to be further elucidated. Here, we show that PtrMTA (Populus trichocarpa methyltransferase) was colocalized with PtrFIP37 in the nucleus. Importantly, the PtrMTA-overexpressing plants significantly increased the density of trichomes and exhibited a more developed root system than that of wild-type controls. Moreover, we found that PtrMTA-overexpressing plants had better tolerance to drought stress. We also found PtrMTA was a component of the m6A methyltransferase complex, which participated in the formation of m6A methylation in poplar. Taken together, these results demonstrate that PtrMTA is involved in drought resistance by affecting the development of trichomes and roots, which will provide new clues for the study of RNA m6A modification and expand our understanding of the epigenetic molecular mechanism in woody plants.
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Chmielowska-Bąk J, Arasimowicz-Jelonek M, Deckert J. In search of the mRNA modification landscape in plants. BMC PLANT BIOLOGY 2019; 19:421. [PMID: 31610789 PMCID: PMC6791028 DOI: 10.1186/s12870-019-2033-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 09/12/2019] [Indexed: 05/09/2023]
Abstract
BACKGROUND Precise regulation of gene expression is indispensable for the proper functioning of organisms in both optimal and challenging conditions. The most commonly known regulative mechanisms include the modulation of transcription, translation and adjustment of the transcript, and protein half-life. New players have recently emerged in the arena of gene expression regulators - chemical modifications of mRNAs. MAIN TEXT The latest studies show that modified ribonucleotides affect transcript splicing, localization, secondary structures, interaction with other molecules and translation efficiency. Thus far, attention has been focused mostly on the most widespread mRNA modification - adenosine methylation at the N6 position (m6A). However, initial reports on the formation and possible functions of other modified ribonucleotides, such as cytosine methylated at the 5' position (m5C), 8-hydroxyguanosine (8-OHG) and 8-nitroguanosine (8-NO2G), have started to appear in the literature. Additionally, some reports indicate that pseudouridine (Ψ) is present in mRNAs and might perform important regulatory functions in eukaryotic cells. The present review summarizes current knowledge regarding the above-mentioned modified ribonucleotides (m6A, m5C, 8-OHG, 8-NO2G) in transcripts across various plant species, including Arabidopsis, rice, sunflower, wheat, soybean and potato. CONCLUSIONS Chemical modifications of ribonucleotides affect mRNA stability and translation efficiency. They thus constitute a newly discovered layer of gene expression regulation and have a profound effect on the development and functioning of various organisms, including plants.
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Affiliation(s)
- Jagna Chmielowska-Bąk
- Department of Plant Ecophysiology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
| | - Magdalena Arasimowicz-Jelonek
- Department of Plant Ecophysiology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - Joanna Deckert
- Department of Plant Ecophysiology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
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Yue H, Nie X, Yan Z, Weining S. N6-methyladenosine regulatory machinery in plants: composition, function and evolution. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:1194-1208. [PMID: 31070865 PMCID: PMC6576107 DOI: 10.1111/pbi.13149] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 04/28/2019] [Accepted: 05/01/2019] [Indexed: 05/04/2023]
Abstract
N6-methyladenosine (m6A) RNA methylation, one of the most pivotal internal modifications of RNA, is a conserved post-transcriptional mechanism to enrich and regulate genetic information in eukaryotes. The scope and function of this modification in plants has been an intense focus of study, especially in model plant systems. The characterization of plant m6A writers, erasers and readers, as well as the elucidation of their functions, is currently one of the most fascinating hotspots in plant biology research. The functional analysis of m6A in plants will be booming in the foreseeable future, which could contribute to crop genetic improvement through epitranscriptome manipulation. In this review, we systematically analysed and summarized recent advances in the understanding of the structure and composition of plant m6A regulatory machinery, and the biological functions of m6A in plant growth, development and stress response. Finally, our analysis showed that the evolutionary relationships between m6A modification components were highly conserved across the plant kingdom.
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Affiliation(s)
- Hong Yue
- College of Life SciencesState Key Laboratory of Crop Stress Biology in Arid AreasNorthwest A&F UniversityYanglingShaanxiChina
| | - Xiaojun Nie
- College of Life SciencesState Key Laboratory of Crop Stress Biology in Arid AreasNorthwest A&F UniversityYanglingShaanxiChina
| | - Zhaogui Yan
- College of Horticulture and Forestry SciencesHuazhong Agricultural UniversityWuhanHubeiChina
| | - Song Weining
- College of Life SciencesState Key Laboratory of Crop Stress Biology in Arid AreasNorthwest A&F UniversityYanglingShaanxiChina
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14
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Moghimi N, Desai JS, Bheemanahalli R, Impa SM, Vennapusa AR, Sebela D, Perumal R, Doherty CJ, Jagadish SVK. New candidate loci and marker genes on chromosome 7 for improved chilling tolerance in sorghum. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:3357-3371. [PMID: 30949711 DOI: 10.1093/jxb/erz143] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/20/2019] [Indexed: 06/09/2023]
Abstract
Sorghum is often exposed to suboptimal low temperature stress under field conditions, particularly at the seedling establishment stage. Enhancing chilling tolerance will facilitate earlier planting and so minimize the negative impacts of other stresses experienced at later growth stages. Genome-wide association mapping was performed on a sorghum association panel grown under control (30/20 °C; day/night) and chilling (20/10 °C) conditions. Genomic regions on chromosome 7, controlling the emergence index and seedling (root and shoot) vigor, were associated with increased chilling tolerance but they did not co-localize with undesirable tannin content quantitative trait loci (QTLs). Shoot and root samples from highly contrasting haplotype pairs expressing differential responses to chilling stress were used to identify candidate genes. Three candidate genes (an alpha/beta hydrolase domain protein, a DnaJ/Hsp40 motif-containing protein, and a YTH domain-containing RNA-binding protein) were expressed at significantly higher levels under chilling stress in the tolerant haplotype compared with the sensitive haplotype and BTx623. Moreover, two CBF/DREB1A transcription factors on chromosome 2 showed a divergent response to chilling in the contrasting haplotypes. These studies identify haplotype differences on chromosome 7 that modulate chilling tolerance by either regulating CBF or feeding back into this signaling pathway. We have identified new candidate genes that will be useful markers in ongoing efforts to develop tannin-free chilling-tolerant sorghum hybrids.
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Affiliation(s)
- Naghmeh Moghimi
- Department of Agronomy, Kansas State University, Manhattan, KS, USA
| | - Jigar S Desai
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA
| | | | - Somayanda M Impa
- Department of Agronomy, Kansas State University, Manhattan, KS, USA
| | | | - David Sebela
- Department of Agronomy, Kansas State University, Manhattan, KS, USA
| | - Ramasamy Perumal
- Agricultural Research Center, Kansas State University, Hays, KS, USA
| | - Colleen J Doherty
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA
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Li Z, Zhao P, Xia Q. Epigenetic Methylations on N6-Adenine and N6-Adenosine with the same Input but Different Output. Int J Mol Sci 2019; 20:ijms20122931. [PMID: 31208067 PMCID: PMC6627651 DOI: 10.3390/ijms20122931] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 12/15/2022] Open
Abstract
Epigenetic modifications on individual bases in DNA and RNA can encode inheritable genetic information beyond the canonical bases. Among the nucleic acid modifications, DNA N6-methadenine (6mA) and RNA N6-methyladenosine (m6A) have recently been well-studied due to the technological development of detection strategies and the functional identification of modification enzymes. The current findings demonstrate a wide spectrum of 6mA and m6A distributions from prokaryotes to eukaryotes and critical roles in multiple cellular processes. It is interesting that the processes of modification in which the methyl group is added to adenine and adenosine are the same, but the outcomes of these modifications in terms of their physiological impacts in organisms are quite different. In this review, we summarize the latest progress in the study of enzymes involved in the 6mA and m6A methylation machinery, including methyltransferases and demethylases, and their functions in various biological pathways. In particular, we focus on the mechanisms by which 6mA and m6A regulate the expression of target genes, and we highlight the future challenges in epigenetic regulation.
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Affiliation(s)
- Zhiqing Li
- Biological Science Research Center, Southwest University, Chongqing 400715, China.
- Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China.
| | - Ping Zhao
- Biological Science Research Center, Southwest University, Chongqing 400715, China.
- Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China.
| | - Qingyou Xia
- Biological Science Research Center, Southwest University, Chongqing 400715, China.
- Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing 400715, China.
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16
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Zhu W, Wang JZ, Xu Z, Cao M, Hu Q, Pan C, Guo M, Wei JF, Yang H. Detection of N6‑methyladenosine modification residues (Review). Int J Mol Med 2019; 43:2267-2278. [PMID: 31017262 PMCID: PMC6488182 DOI: 10.3892/ijmm.2019.4169] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 04/12/2019] [Indexed: 12/30/2022] Open
Abstract
Among a number of mRNA modifications, N6‑methyladenosine (m6A) modification is the most common type in eukaryotes and nuclear‑replicating viruses. m6A has a significant role in numerous cancer types, including leukemia, brain tumors, liver cancer, breast cancer and lung cancer. Although m6A methyltransferases are essential during RNA modifications, the biological functions of m6A and the underlying mechanisms remain to be fully elucidated, predominantly due to the limited detection methods for m6A. In the present review, the currently available m6A detection methods and the respective scope of their applications are presented to facilitate the further investigation of the roles of m6A in biological process.
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Affiliation(s)
- Wei Zhu
- Research Division of Clinical Pharmacology
| | - Jing-Zi Wang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | | | - Mengda Cao
- Research Division of Clinical Pharmacology
| | - Qiaoli Hu
- Research Division of Clinical Pharmacology
| | - Chen Pan
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 210000, P.R. China
| | - Miao Guo
- Research Division of Clinical Pharmacology
| | - Ji-Fu Wei
- Research Division of Clinical Pharmacology
| | - Haiwei Yang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
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17
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Shen L, Liang Z, Wong CE, Yu H. Messenger RNA Modifications in Plants. TRENDS IN PLANT SCIENCE 2019; 24:328-341. [PMID: 30745055 DOI: 10.1016/j.tplants.2019.01.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/16/2019] [Accepted: 01/17/2019] [Indexed: 05/21/2023]
Abstract
Over 160 distinct RNA modifications are known and collectively termed the epitranscriptome. Some of these modifications have been discovered in mRNA, uncovering a new layer of gene regulation. Transcriptome-wide mapping of epitranscriptomic codes and the discovery of their writers, erasers, and readers that dynamically install, remove, and interpret RNA modifications, respectively, are fundamental to understanding the epitranscriptome. Recent technologies have enabled the transcriptome-wide profiling of several mRNA modifications in Arabidopsis thaliana, providing key insights into regulating these modifications and their effects on plant development. Here we review technological innovations and recent progress in epitranscriptomics, with specific focus on N6-methyladenosine (m6A), 5-methylcytosine (m5C), uridylation, and their roles in multiple aspects of plant development.
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Affiliation(s)
- Lisha Shen
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, 117604, Singapore; These authors contributed equally to this manuscript.
| | - Zhe Liang
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore; These authors contributed equally to this manuscript
| | - Chui Eng Wong
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, 117604, Singapore; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore
| | - Hao Yu
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, 117604, Singapore; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore.
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18
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N⁶-methyladenosine (m⁶A): Revisiting the Old with Focus on New, an Arabidopsis thaliana Centered Review. Genes (Basel) 2018; 9:genes9120596. [PMID: 30513695 PMCID: PMC6316766 DOI: 10.3390/genes9120596] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 11/26/2018] [Accepted: 11/28/2018] [Indexed: 01/24/2023] Open
Abstract
N6-methyladenosine (m6A) is known to occur in plant and animal messenger RNAs (mRNAs) since the 1970s. However, the scope and function of this modification remained un-explored till very recently. Since the beginning of this decade, owing to major technological breakthroughs, the interest in m6A has peaked again. Similar to animal mRNAs, plant mRNAs are also m6A methylated, within a specific sequence motif which is conserved across these kingdoms. m6A has been found to be pivotal for plant development and necessary for processes ranging from seed germination to floral development. A wide range of proteins involved in methylation of adenosine have been identified alongside proteins that remove or identify m6A. This review aims to put together the current knowledge regarding m6A in Arabidopsis thaliana.
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19
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Duan HC, Wang Y, Jia G. Dynamic and reversible RNA N 6 -methyladenosine methylation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 10:e1507. [PMID: 30252201 DOI: 10.1002/wrna.1507] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/01/2018] [Accepted: 08/20/2018] [Indexed: 12/31/2022]
Abstract
N6 -methyladenosine (m6 A) is the most abundant internal chemical modification in eukaryotic messenger RNAs (mRNAs). The discovery in 2011 that m6 A is reversed by the fat mass and obesity-associated protein stimulated extensive worldwide research efforts on the regulatory biological functions of dynamic m6 A and other RNA modifications. The epitranscriptomic mark m6 A is written, read, and erased through the activities of a complicated network of enzymes and other proteins. m6 A-binding proteins read m6 A marks and transduce their downstream regulatory effects by altering RNA metabolic processes. In this review, we summarize the current knowledge of m6 A modifications, with particular focus on the functions of its writer, eraser, and reader proteins in posttranscriptional gene regulation and discuss the impact of m6 A marks on human health. This article is categorized under: RNA Processing > RNA Editing and Modification RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Hong-Chao Duan
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Ye Wang
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Guifang Jia
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
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20
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Vandivier LE, Gregory BD. New insights into the plant epitranscriptome. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:4659-4665. [PMID: 30020491 DOI: 10.1093/jxb/ery262] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/09/2018] [Indexed: 06/08/2023]
Abstract
Throughout all kingdoms of life, ribonucleotides are marked with covalent chemical modifications that change the structure and binding properties of modified RNA molecules. These marks are deposited by 'writer' proteins, recognized by 'readers', and removed by 'erasers', thus forming an epitranscriptomic system of marks and binding proteins directly analogous to the epigenome. Recent advances in marrying classical biochemical techniques with high-throughput sequencing have enabled detailed mapping of plant epitranscriptomic marks, which in turn yielded insights into how these marks regulate a host of biological processes, from shoot stem cell fate to floral transition and from leaf development to viral activity. In this review, we highlight recent developments in the study of plant epitranscriptomics, with an emphasis on N6-methyladenosine (m6A) and 5-methylcytosine (m5C). These studies have advanced the field beyond descriptive mapping or isolated genetic studies, and produced a more nuanced understanding of how components of the epitranscriptome and their binding proteins directly regulate critical aspects of plant biology.
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Affiliation(s)
- Lee E Vandivier
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Brian D Gregory
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
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21
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Dynamic transcriptomic m 6A decoration: writers, erasers, readers and functions in RNA metabolism. Cell Res 2018; 28:616-624. [PMID: 29789545 PMCID: PMC5993786 DOI: 10.1038/s41422-018-0040-8] [Citation(s) in RCA: 920] [Impact Index Per Article: 153.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 04/22/2018] [Indexed: 02/06/2023] Open
Abstract
N6-methyladenosine (m6A) is a chemical modification present in multiple RNA species, being most abundant in mRNAs. Studies on enzymes or factors that catalyze, recognize, and remove m6A have revealed its comprehensive roles in almost every aspect of mRNA metabolism, as well as in a variety of physiological processes. This review describes the current understanding of the m6A modification, particularly the functions of its writers, erasers, readers in RNA metabolism, with an emphasis on its role in regulating the isoform dosage of mRNAs.
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23
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Abstract
The recent discovery of reversible mRNA methylation has opened a new realm of post-transcriptional gene regulation in eukaryotes. The identification and functional characterization of proteins that specifically recognize RNA N6-methyladenosine (m6A) unveiled it as a modification that cells utilize to accelerate mRNA metabolism and translation. N6-adenosine methylation directs mRNAs to distinct fates by grouping them for differential processing, translation and decay in processes such as cell differentiation, embryonic development and stress responses. Other mRNA modifications, including N1-methyladenosine (m1A), 5-methylcytosine (m5C) and pseudouridine, together with m6A form the epitranscriptome and collectively code a new layer of information that controls protein synthesis.
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Affiliation(s)
- Boxuan Simen Zhao
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, Howard Hughes Medical Institute, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA
| | - Ian A Roundtree
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, Howard Hughes Medical Institute, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA
| | - Chuan He
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, Howard Hughes Medical Institute, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA
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24
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Zhou X, He L, Wan D, Yang H, Yao K, Wu G, Wu X, Yin Y. Methionine restriction on lipid metabolism and its possible mechanisms. Amino Acids 2016; 48:1533-40. [DOI: 10.1007/s00726-016-2247-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 04/29/2016] [Indexed: 12/26/2022]
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Li Y, Wang X, Li C, Hu S, Yu J, Song S. Transcriptome-wide N⁶-methyladenosine profiling of rice callus and leaf reveals the presence of tissue-specific competitors involved in selective mRNA modification. RNA Biol 2015; 11:1180-8. [PMID: 25483034 PMCID: PMC5155352 DOI: 10.4161/rna.36281] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
N(6)-methyladenosine (m(6)A) is the most prevalent internal modification present in mRNAs of all higher eukaryotes. With the development of MeRIP-seq technique, in-depth identification of mRNAs with m(6)A modification becomes feasible. Here we present a transcriptome-wide m(6)A modification profiling effort for rice transcriptomes of differentiated callus and leaf, which yields 8,138 and 14,253 m(6)A-modified genes, respectively. The m(6)A peak (m(6)A-modified nucleotide position on mRNAs) distribution exhibits preference toward both translation termination and initiation sites. The m(6)A peak enrichment is negatively correlated with gene expression and weakly positively correlated with certain gene features, such as exon length and number. By comparing m(6)A-modified genes between the 2 samples, we define 1,792 and 6,508 tissue-specific m(6)A-modified genes (TSMGs) in callus and leaf, respectively. Among which, 626 and 5,509 TSMGs are actively expressed in both tissues but are selectively m(6)A-modified (SMGs) only in one of the 2 tissues. Further analyses reveal characteristics of SMGs: (1) Most SMGs are differentially expressed between callus and leaf. (2) Two conserved RNA-binding motifs, predicted to be recognized by PUM and RNP4F, are significantly over-represented in SMGs. (3) GO enrichment analysis shows that SMGs in callus mainly participate in transcription regulator/factor activity whereas SMGs in leaf are mainly involved in plastid and thylakoid. Our results suggest the presence of tissue-specific competitors involved in SMGs. These findings provide a resource for plant RNA epitranscriptomic studies and further enlarge our knowledge on the function of RNA m(6)A modification.
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Affiliation(s)
- Yuli Li
- a CAS Key Laboratory of Genome Sciences and Information ; Beijing Institute of Genomics; Chinese Academy of Sciences ; Beijing , P.R. China
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Abstract
N6-methyladenosine (m6A) is the most prevalent internal modification that occurs in the messenger RNA (mRNA) of most eukaryotes. In this review, Yue et al. summarize recent progress in the study of the m6A mRNA methylation machineries across eukaryotes and discuss their newly uncovered roles in post-transcriptional gene expression regulation. N6-methyladenosine (m6A) is the most prevalent and internal modification that occurs in the messenger RNAs (mRNA) of most eukaryotes, although its functional relevance remained a mystery for decades. This modification is installed by the m6A methylation “writers” and can be reversed by demethylases that serve as “erasers.” In this review, we mainly summarize recent progress in the study of the m6A mRNA methylation machineries across eukaryotes and discuss their newly uncovered biological functions. The broad roles of m6A in regulating cell fates and embryonic development highlight the existence of another layer of epigenetic regulation at the RNA level, where mRNA is subjected to chemical modifications that affect protein expression.
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Affiliation(s)
- Yanan Yue
- Department of Chemistry, Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois 60637, USA
| | - Jianzhao Liu
- Department of Chemistry, Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois 60637, USA
| | - Chuan He
- Department of Chemistry, Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA; Howard Hughes Medical Institute, The University of Chicago, Chicago, Illinois 60637, USA
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Liu J, Jia G. Methylation modifications in eukaryotic messenger RNA. J Genet Genomics 2013; 41:21-33. [PMID: 24480744 DOI: 10.1016/j.jgg.2013.10.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 10/09/2013] [Accepted: 10/20/2013] [Indexed: 10/26/2022]
Abstract
RNA methylation modifications have been found for decades of years, which occur at different RNA types of numerous species, and their distribution is species-specific. However, people rarely know their biological functions. There are several identified methylation modifications in eukaryotic messenger RNA (mRNA), such as N(7)-methylguanosine (m(7)G) at the cap, N(6)-methyl-2'-O-methyladenosine (m(6)Am), 2'-O-methylation (Nm) within the cap and the internal positions, and internal N(6)-methyladenosine (m(6)A) and 5-methylcytosine (m(5)C). Among them, m(7)G cap was studied more clearly and found to have vital roles in several important mRNA processes like mRNA translation, stability and nuclear export. m(6)A as the most abundant modification in mRNA was found in the 1970s and has been proposed to function in mRNA splicing, translation, stability, transport and so on. m(6)A has been discovered as the first RNA reversible modification which is demethylated directly by human fat mass and obesity associated protein (FTO) and its homolog protein, alkylation repair homolog 5 (ALKBH5). FTO has a special demethylation mechanism that demethylases m(6)A to A through two over-oxidative intermediate states: N(6)-hydroxymethyladenosine (hm(6)A) and N(6)-formyladenosine (f(6)A). The two newly discovered m(6)A demethylases, FTO and ALKBH5, significantly control energy homeostasis and spermatogenesis, respectively, indicating that the dynamic and reversible m(6)A, analogous to DNA and histone modifications, plays broad roles in biological kingdoms and brings us an emerging field "RNA Epigenetics". 5-methylcytosine (5mC) as an epigenetic mark in DNA has been studied widely, but m(5)C in mRNA is seldom explored. The bisulfide sequencing showed m(5)C is another abundant modification in mRNA, suggesting that it might be another RNA epigenetic mark. This review focuses on the main methylation modifications in mRNA to describe their formation, distribution, function and demethylation from the current knowledge and to provide future perspectives on functional studies.
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Affiliation(s)
- Jun Liu
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Guifang Jia
- Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
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Sibbritt T, Patel HR, Preiss T. Mapping and significance of the mRNA methylome. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:397-422. [PMID: 23681756 DOI: 10.1002/wrna.1166] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 03/20/2013] [Accepted: 03/22/2013] [Indexed: 12/25/2022]
Abstract
Internal methylation of eukaryotic mRNAs in the form of N6-methyladenosine (m(6)A) and 5-methylcytidine (m(5)C) has long been known to exist, but progress in understanding its role was hampered by difficulties in identifying individual sites. This was recently overcome by high-throughput sequencing-based methods that mapped thousands of sites for both modifications throughout mammalian transcriptomes, with most sites found in mRNAs. The topology of m(6)A in mouse and human revealed both conserved and variable sites as well as plasticity in response to extracellular cues. Within mRNAs, m(5)C and m(6)A sites were relatively depleted in coding sequences and enriched in untranslated regions, suggesting functional interactions with post-transcriptional gene control. Finer distribution analyses and preexisting literature point toward roles in the regulation of mRNA splicing, translation, or decay, through an interplay with RNA-binding proteins and microRNAs. The methyltransferase (MTase) METTL3 'writes' m(6)A marks on mRNA, whereas the demethylase FTO can 'erase' them. The RNA:m(5)C MTases NSUN2 and TRDMT1 have roles in tRNA methylation but they also act on mRNA. Proper functioning of these enzymes is important in development and there are clear links to human disease. For instance, a common variant of FTO is a risk allele for obesity carried by 1 billion people worldwide and mutations cause a lethal syndrome with growth retardation and brain deficits. NSUN2 is linked to cancer and stem cell biology and mutations cause intellectual disability. In this review, we summarize the advances, open questions, and intriguing possibilities in this emerging field that might be called RNA modomics or epitranscriptomics.
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Affiliation(s)
- Tennille Sibbritt
- Genome Biology Department, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
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Niu Y, Zhao X, Wu YS, Li MM, Wang XJ, Yang YG. N6-methyl-adenosine (m6A) in RNA: an old modification with a novel epigenetic function. GENOMICS PROTEOMICS & BIOINFORMATICS 2012; 11:8-17. [PMID: 23453015 PMCID: PMC4357660 DOI: 10.1016/j.gpb.2012.12.002] [Citation(s) in RCA: 318] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 12/10/2012] [Accepted: 12/11/2012] [Indexed: 12/02/2022]
Abstract
N6-methyl-adenosine (m6A) is one of the most common and abundant modifications on RNA molecules present in eukaryotes. However, the biological significance of m6A methylation remains largely unknown. Several independent lines of evidence suggest that the dynamic regulation of m6A may have a profound impact on gene expression regulation. The m6A modification is catalyzed by an unidentified methyltransferase complex containing at least one subunit methyltransferase like 3 (METTL3). m6A modification on messenger RNAs (mRNAs) mainly occurs in the exonic regions and 3′-untranslated region (3′-UTR) as revealed by high-throughput m6A-seq. One significant advance in m6A research is the recent discovery of the first two m6A RNA demethylases fat mass and obesity-associated (FTO) gene and ALKBH5, which catalyze m6A demethylation in an α-ketoglutarate (α-KG)- and Fe2+-dependent manner. Recent studies in model organisms demonstrate that METTL3, FTO and ALKBH5 play important roles in many biological processes, ranging from development and metabolism to fertility. Moreover, perturbation of activities of these enzymes leads to the disturbed expression of thousands of genes at the cellular level, implicating a regulatory role of m6A in RNA metabolism. Given the vital roles of DNA and histone methylations in epigenetic regulation of basic life processes in mammals, the dynamic and reversible chemical m6A modification on RNA may also serve as a novel epigenetic marker of profound biological significances.
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Affiliation(s)
- Yamei Niu
- Disease Genomics and Individualized Medicine Laboratory, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
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Jia G, Fu Y, He C. Reversible RNA adenosine methylation in biological regulation. Trends Genet 2012; 29:108-15. [PMID: 23218460 DOI: 10.1016/j.tig.2012.11.003] [Citation(s) in RCA: 289] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 11/01/2012] [Accepted: 11/05/2012] [Indexed: 01/20/2023]
Abstract
N(6)-methyladenosine (m(6)A) is a ubiquitous modification in mRNA and other RNAs across most eukaryotes. For many years, however, the exact functions of m(6)A were not clearly understood. The discovery that the fat mass and obesity-associated protein (FTO) is an m(6)A demethylase indicates that this modification is reversible and dynamically regulated, suggesting that it has regulatory roles. In addition, it has been shown that m(6)A affects cell fate decisions in yeast and plant development. Recent affinity-based m(6)A profiling in mouse and human cells further showed that this modification is a widespread mark in coding and noncoding RNA (ncRNA) transcripts and is likely dynamically regulated throughout developmental processes. Therefore, reversible RNA methylation, analogous to reversible DNA and histone modifications, may affect gene expression and cell fate decisions by modulating multiple RNA-related cellular pathways, which potentially provides rapid responses to various cellular and environmental signals, including energy and nutrient availability in mammals.
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Affiliation(s)
- Guifang Jia
- Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, 929 East 57th Street, Chicago, IL 60637, USA
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31
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Bodi Z, Zhong S, Mehra S, Song J, Graham N, Li H, May S, Fray RG. Adenosine Methylation in Arabidopsis mRNA is Associated with the 3' End and Reduced Levels Cause Developmental Defects. FRONTIERS IN PLANT SCIENCE 2012; 3:48. [PMID: 22639649 PMCID: PMC3355605 DOI: 10.3389/fpls.2012.00048] [Citation(s) in RCA: 192] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 02/27/2012] [Indexed: 05/19/2023]
Abstract
We previously showed that the N6-methyladenosine (m(6)A) mRNA methylase is essential during Arabidopsis thaliana embryonic development. We also demonstrated that this modification is present at varying levels in all mature tissues. However, the requirement for the m(6)A in the mature plant was not tested. Here we show that a 90% reduction in m(6)A levels during later growth stages gives rise to plants with altered growth patterns and reduced apical dominance. The flowers of these plants commonly show defects in their floral organ number, size, and identity. The global analysis of gene expression from reduced m(6)A plants show that a significant number of down-regulated genes are involved in transport, or targeted transport, and most of the up-regulated genes are involved in stress and stimulus response processes. An analysis of m(6)A distribution in fragmented mRNA suggests that the m(6)A is predominantly positioned toward the 3' end of transcripts in a region 100-150 bp before the poly(A) tail. In addition to the analysis of the phenotypic changes in the low methylation Arabidopsis plants we will review the latest advances in the field of mRNA internal methylation.
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Affiliation(s)
- Zsuzsanna Bodi
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Silin Zhong
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Surbhi Mehra
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Jie Song
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Neil Graham
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Hongying Li
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Sean May
- School of Biosciences, University of NottinghamLoughborough, UK
| | - Rupert George Fray
- School of Biosciences, University of NottinghamLoughborough, UK
- *Correspondence: Rupert George Fray, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK. e-mail:
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Abstract
N6-Methyladenosine (m6A) is a modified base present in the mRNA of all higher eukaryotes and in Saccharomyces cerevisiae, where there is an increase in m6A levels during sporulation. The methyltransferase, Ime4, is responsible for this modification and has a role in the initiation of meiosis. However, neither the function, nor the extent of distribution of this nucleotide modification is established. We demonstrate that in S. cerevisiae, substantial levels of internal adenosine methylation are present in the GpA context in mRNA from sporulating cells, which is consistent with the preferred methylation consensus of higher eukaryotes. Based upon our quantification data, every second transcript could contain one m6A during meiosis. As methylation is distributed across all mRNA size ranges, it is likely that m6A is not limited to a small population of messages. We developed a new antibody based method for identifying m6A containing messages, and using this method the transcripts of three key, early regulators of meiosis, IME1, IME2 and IME4 itself, were identified as being methylated. The position of m6A in IME2 was narrowed down to a region in the 3′-end. Methylation of these and other targets suggests mechanisms by which IME4 could control developmental choices leading to meiosis.
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Affiliation(s)
- Zsuzsanna Bodi
- School of Biosciences, Plant Sciences Division, University of Nottingham, Sutton Bonington, Loughborough LE12 5RD, UK
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Zhong S, Li H, Bodi Z, Button J, Vespa L, Herzog M, Fray RG. MTA is an Arabidopsis messenger RNA adenosine methylase and interacts with a homolog of a sex-specific splicing factor. THE PLANT CELL 2008; 20:1278-88. [PMID: 18505803 PMCID: PMC2438467 DOI: 10.1105/tpc.108.058883] [Citation(s) in RCA: 431] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 04/23/2008] [Accepted: 05/12/2008] [Indexed: 05/18/2023]
Abstract
N6-Methyladenosine is a ubiquitous modification identified in the mRNA of numerous eukaryotes, where it is present within both coding and noncoding regions. However, this base modification does not alter the coding capacity, and its biological significance remains unclear. We show that Arabidopsis thaliana mRNA contains N6-methyladenosine at levels similar to those previously reported for animal cells. We further show that inactivation of the Arabidopsis ortholog of the yeast and human mRNA adenosine methylase (MTA) results in failure of the developing embryo to progress past the globular stage. We also demonstrate that the arrested seeds are deficient in mRNAs containing N6-methyladenosine. Expression of MTA is strongly associated with dividing tissues, particularly reproductive organs, shoot meristems, and emerging lateral roots. Finally, we show that MTA interacts in vitro and in vivo with At FIP37, a homolog of the Drosophila protein FEMALE LETHAL2D and of human WILMS' TUMOUR1-ASSOCIATING PROTEIN. The results reported here provide direct evidence for an essential function for N6-methyladenosine in a multicellular eukaryote, and the interaction with At FIP37 suggests possible RNA processing events that might be regulated or altered by this base modification.
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Affiliation(s)
- Silin Zhong
- Plant Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, United Kingdom
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34
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Leach RA, Tuck MT. Methionine depletion induces transcription of the mRNA (N6-adenosine)methyltransferase. Int J Biochem Cell Biol 2001; 33:1116-28. [PMID: 11551827 DOI: 10.1016/s1357-2725(01)00072-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study examines the genetic expression of the S-adenosyl-L-methionine binding subunit of the mRNA (N6-adenosine)methyltransferase (MT-A70) in cultured cells under conditions known to affect transmethylation reactions. Methionine dependence, disrupted methionine metabolism, and increased transmethylation reactions are all phenotypes characteristic of cancer cells. The results show that both methionine depletion and inhibition of S-adenosyl-L-methionine formation can induce up to a four-fold increase in transcription of this S-adenosyl-L-methionine binding subunit. The two splice-variant mRNAs produced from the MT-A70 gene are transcribed at different rates depending on the level of S-adenosyl-L-methionine inhibition. This result may reflect differing Km values toward the substrate for the different enzyme isoforms. 3-Deazaadenosine, an inhibitor known to block certain mRNA transmethylations, was shown to have no effect on MT-A70 gene expression. This result indicates that the control of MT-A70 gene expression is directly related to methionine availability and the subsequent synthesis of S-adenosyl-L-methionine.
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Affiliation(s)
- R A Leach
- Department of Biological Sciences, Ohio University, Athens, OH 45701, USA
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35
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Tuck MT, Wiehl PE, Pan T. Inhibition of 6-methyladenine formation decreases the translation efficiency of dihydrofolate reductase transcripts. Int J Biochem Cell Biol 1999; 31:837-51. [PMID: 10481270 DOI: 10.1016/s1357-2725(99)00041-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Cycloleucine was used to inhibit the formation of internal N6-methyladenosine residues in the messenger ribonucleic acid transcripts from cultured methotrexate resistant mouse sarcoma cells. Cells cultured in cycloleucine produced transcripts deficient in N6-methyladenosine residues and the 2'-O-methylated nucleosides of the cap structure; however, the formation of the 7-methylguanine nucleoside of the cap was not effected. Cytoplasmic polyadenylated transcripts were isolated from cells which had been pretreated with media containing cycloleucine and translated in an in vitro translation assay. The levels of translated dihydrofolate reductase were then analyzed by polyacrylamide gel electrophoresis. The amount of dihydrofolate reductase protein produced from the transcripts of the cycloleucine treated cells was 20% less than untreated transcripts. Ribonuclease protection assays demonstrated little difference in the cytoplasmic levels of dihydrofolate reductase transcripts between treated and untreated cells suggesting that the decrease in translation efficiency was not caused solely by an alteration in the processing or cytoplasmic transport of the transcripts. Translation of in vitro transcribed transcripts showed the presence of 2'-O-methylated nucleosides in the cap structure had a negative effect on translation efficiency, demonstrating that the results observed from cycloleucine treatment could not be due to the inhibition of 2'-O-methylation in the cap. These experiments therefore suggest that an inhibition of N6-methyladenosine residues in dihydrofolate reductase transcripts significantly alters their rate of translation.
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Affiliation(s)
- M T Tuck
- Department of Chemistry and Biochemistry, Ohio University, Athens 45701, USA.
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36
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Heilman KL, Leach RA, Tuck MT. Internal 6-methyladenine residues increase the in vitro translation efficiency of dihydrofolate reductase messenger RNA. Int J Biochem Cell Biol 1996; 28:823-9. [PMID: 8925412 DOI: 10.1016/1357-2725(96)00014-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
N6-Methyladenosine (m6A) is found internally in a number of mRNA molecules from higher eucaryotic cells. In these investigations, it was found that the presence of m6A residues increase the in vitro translation efficiency of capped T7 transcripts of mouse dihydrofolate reductase (DHFR) mRNA. Using an in vitro rabbit reticulocyte translation system, the formation of internal m6A residues in the DHFR transcripts resulted in a 1.5-fold increase in translated DHFR compared to transcripts void of internal m6A residues. Translation in a wheat germ system, however, resulted in no increase in translation efficiency upon m6A formation, suggesting that the mechanism may be species-specific.
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Affiliation(s)
- K L Heilman
- Department of Chemistry, Ohio University, Athens 45701, USA
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37
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Tuck MT, James CB, Kelder B, Kopchick JJ. Elevation of internal 6-methyladenine mRNA methyltransferase activity after cellular transformation. Cancer Lett 1996; 103:107-13. [PMID: 8616802 DOI: 10.1016/0304-3835(96)04203-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A comparison of internal 6-methyladenine mRNA methyltransferase activity in a variety of cell types demonstrated an 8-15-fold increase as a result of cellular transformation. Utilizing adenovirus transformed rat embryo cells, it was found that the increase in methyltransferase activity was concomitant with or occurred rapidly after transformation. An 80-fold increase in activity was observed in the cells isolated from the transformed foci and remained elevated through subsequent passages. The relationship between methyltransferase activity and tumor formation was also investigated. High level expression of the avian ski oncogene in mouse L cells causes a reversion of the transformed phenotype to a non-transformed state, and resulted in a 47% reduction in the specific activity of the methyltransferase as compared with mock transfected cells.
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Affiliation(s)
- M T Tuck
- Department of Chemistry, Clippinger Laboratories, Ohio University, Athens 45701, USA
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38
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Tuck MT. Partial purification of a 6-methyladenine mRNA methyltransferase which modifies internal adenine residues. Biochem J 1992; 288 ( Pt 1):233-40. [PMID: 1445268 PMCID: PMC1132103 DOI: 10.1042/bj2880233] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Two forms of a 6-methyladenine mRNA methyltransferase have been partially purified using a T7 transcript coding for mouse dihydrofolate reductase as an RNA substrate. Both enzyme forms modify internal adenine residues within the RNA substrate. The enzymes were purified 357- and 37-fold respectively from nuclear salt extracts prepared from HeLa cells using DEAE-cellulose and phosphocellulose chromatography. The activity of the first form of the enzyme eluted from DEAE-cellulose (major form) was at least 3-fold greater than that of the second (minor form). H.p.l.c. analysis of the hydrolysed, methylated mRNA substrates demonstrated that both forms of the enzyme produced only 6-methyladenine. The two forms of the enzyme differed in their RNA substrate specificity as well as in the dependence for a 5' cap structure. The 6-methyladenine mRNA methyltransferase activity was found to be elevated in HeLa nuclei as compared with nuclear extracts from rat kidney and brain. Enzymic activity could not be detected in nuclei from either normal rat liver or regenerating rat liver. In the case of the HeLa cell, activity could only be detected in nuclear extracts, with a small amount in the ribosomal fraction. Other HeLa subcellular fractions were void of activity.
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Affiliation(s)
- M T Tuck
- Department of Chemistry, Ohio University, Athens 45701
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39
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Tuck MT. The formation of internal 6-methyladenine residues in eucaryotic messenger RNA. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1992; 24:379-86. [PMID: 1551452 DOI: 10.1016/0020-711x(92)90028-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. The formation of internal 6-methyladenine (m6A) residues in eucaryotic messenger RNA (mRNA) is a postsynthetic modification in which S-adenosyl-L-methionine (SAM) serves as the methyl donor. 2. Of the methyl groups incorporated into mature mRNA 30-50% occur in m6A residues. 3. Although most cellular and certain viral mRNAs contain at least one m6A residue, some transcripts such as those coding for histone and globin are completely lacking in this modification. 4. 6-Methyladenine residues have also been localized to heterogeneous nuclear RNA (HnRNA), and for the most part these residues are conserved during mRNA processing. 5. In all known cases, the m6A residues are also found in a strict consensus sequence, Gm6AC or Am6AC, within the transcript. 6. Although the biological significance of internal adenine methylation in eucaryotic mRNA remains unclear, a great deal of research has indicated that this modification may be required for mRNA transport to the cytoplasm, the selection of splice sites or other RNA processing reactions.
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Affiliation(s)
- M T Tuck
- Department of Chemistry, Ohio University, Athens 45701
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40
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Rana AP, Tuck MT. Analysis and in vitro localization of internal methylated adenine residues in dihydrofolate reductase mRNA. Nucleic Acids Res 1990; 18:4803-8. [PMID: 2395644 PMCID: PMC331949 DOI: 10.1093/nar/18.16.4803] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A T7 RNA transcript coding for mouse dihydrofolate reductase (DHFR) was utilized as a substrate for the N6-methyladenosine mRNA methyltransferase isolated from HeLa cell nuclei. This transcript acted as a 3 fold better substrate than either prolactin mRNA or a synthetic RNA substrate which contained multiple methylation consensus sequences. Formation of internal N6-methyladenine (m6A) residues in the DHFR transcript was shown to increase slightly by the absence of a 7-methylguanine-2'-O-methyl cap structure. Using T7 transcripts from different regions of the DHFR gene, the majority of the m6A residues were localized to the coding region and a segment of the transcript just 3' to the coding region. This data suggests that DHFR mRNA contains multiple methylation sites with most of these sites concentrated in the coding region of the transcript.
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Affiliation(s)
- A P Rana
- Department of Chemistry, Ohio University, Athens 45701
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41
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Horowitz S, Horowitz A, Nilsen TW, Munns TW, Rottman FM. Mapping of N6-methyladenosine residues in bovine prolactin mRNA. Proc Natl Acad Sci U S A 1984; 81:5667-71. [PMID: 6592581 PMCID: PMC391771 DOI: 10.1073/pnas.81.18.5667] [Citation(s) in RCA: 112] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
N6-Methyladenosine (m6A) residues, which are found internally in viral and cellular mRNA populations at the sequences Apm6ApC and Gpm6ApC, have been proposed to play a role in mRNA processing and transport. We have developed a sensitive approach to analyze the level and location of m6A in specific purified cellular mRNAs in an attempt to correlate m6A location with function. Polyadenylylated mRNA is hybridized to cDNA clones representing the full size mRNA under study or fragments of it, and the protected RNA is digested and labeled with polynucleotide kinase in vitro. After enrichment for m6A with anti-m6A antibody, the [32P]-pm6A is separated on TLC plates, and compared with the total amount of radiolabeled nucleotides. Using this combination of in vitro RNA labeling and antibody selection, we were able to detect m6A in purified stable mRNAs that cannot be readily labeled in cells with greater sensitivity than was possible by previous techniques. We applied this technique to bovine prolactin mRNA and showed that this mRNA contains m6A. Moreover, all of the m6A residues in this message are found within the 3' two-thirds of the molecule and are highly concentrated (61%) within a sequence of 108 nucleotides at the 3' noncoding region of the message. The nonrandom distribution of m6A in a specific cellular mRNA, as demonstrated for bovine prolactin, will have to be taken into account when designing a model for m6A function.
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42
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Lane BG, Tumaitis-Kennedy TD. Comparative study of levels of secondary processing in bulk mRNA from dry and germinating wheat embryos. EUROPEAN JOURNAL OF BIOCHEMISTRY 1981; 114:457-63. [PMID: 6113140 DOI: 10.1111/j.1432-1033.1981.tb05167.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
There has been no previous study of levels of secondary processing in the template-active RNA of dry seeds and embryos. Such information is needed to evaluate the role of transcription in changing the cell-free translational capacity of bulk RNA during early imbibition of water by dry wheat embryos [J. Biol. Chem. 255, 5969-5970 (1980)]. Although it probably contains a higher proportion of "hidden breaks' than bulk mRNA from imbibing embryos, bulk mRNA in dry wheat embryos is also "capped' by 7-methylguanosine at 5' termini, devoid of unmethylated "caps', methylated internally (N6-methyladenosine) and polyadenylated at 3' termini. In contrast to other developing systems, there is no evidence that there are signal changes in levels of secondary processing in the bulk mRNA populations which support change in cell-free translational capacity of RNA 1-5 h postimbibition of dry wheat embryos. Change in the pattern of protein synthesis 5-24 h postimbibition also takes place without signal changes in levels of secondary processing in template-active RNA. The analytical data are evaluated and discussed in terms of difficulties allied with comparative analyses of poly(A)-rich RNA from dry and imbibing embryos, the former being refractory to, and the latter being most easily analyzed by, labeling in vivo.
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43
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Nichols J, Welder L. Nucleotides adjacent to N6-methyladenosine in maize poly(A)-containing RNA. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/0304-4211(81)90071-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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44
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Nichols JL, Welder L. A modified nucleotide in the poly(A) tract of maize RNA. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 652:99-108. [PMID: 6163465 DOI: 10.1016/0005-2787(81)90213-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
poly(A)+ RNA was isolated from maize by affinity chromatography on columns of oligo(dT)-cellulose. A modified nucleotide ('X') was detected in ribonuclease T2 digests of the RNA as part of a resistant dinucleotide. The dinucleotide was detected by means of the polynucleotide kinase-mediated transfer of a radioactive phosphate atom from adenosine triphosphate to the 5'-OH position of the dinucleotide. Intact poly(A) tracts were released from poly(A)+ RNA by digestion with ribonuclease T1 and A in a high salt buffer and were isolated by oligo(dT)-cellulose chromatography. The poly(A) preparation was found to consist of a series of polyadenylate fragments which varied in chain length from approximately 17 to greater than 70. The modified nucleotide was shown to occupy an internal position in these poly(A) tracts.
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