1
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Shamnas v M, Singh A, Kumar A, Mishra GP, Sinha SK. Exitrons: offering new roles to retained introns-the novel regulators of protein diversity and utility. AOB PLANTS 2024; 16:plae014. [PMID: 38566894 PMCID: PMC10985678 DOI: 10.1093/aobpla/plae014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 03/15/2024] [Indexed: 04/04/2024]
Abstract
Exitrons are exonic introns. This subclass of intron retention alternative splicing does not contain a Pre-Terminating stop Codon. Therefore, when retained, they are always a part of a protein. Intron retention is a frequent phenomenon predominantly found in plants, which results in either the degradation of the transcripts or can serve as a stable intermediate to be processed upon induction by specific signals or the cell status. Interestingly, exitrons have coding ability and may confer additional attributes to the proteins that retain them. Therefore, exitron-containing and exitron-spliced isoforms will be a driving force for creating protein diversity in the proteome of an organism. This review establishes a basic understanding of exitron, discussing its genesis, key features, identification methods and functions. We also try to depict its other potential roles. The present review also aims to provide a fundamental background to those who found such exitronic sequences in their gene(s) and to speculate the future course of studies.
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Affiliation(s)
- Muhammed Shamnas v
- ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi 110012, India
| | - Akanksha Singh
- ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi 110012, India
- Department of Botany and Plant Pathology, Lilly Hall of Life Sciences, Purdue University, West Lafayette 47906, Indiana, USA
| | - Anuj Kumar
- ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi 110012, India
| | - Gyan Prakash Mishra
- Division of Genetics, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi 110012, India
| | - Subodh Kumar Sinha
- ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi 110012, India
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2
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Dwivedi SL, Quiroz LF, Reddy ASN, Spillane C, Ortiz R. Alternative Splicing Variation: Accessing and Exploiting in Crop Improvement Programs. Int J Mol Sci 2023; 24:15205. [PMID: 37894886 PMCID: PMC10607462 DOI: 10.3390/ijms242015205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Alternative splicing (AS) is a gene regulatory mechanism modulating gene expression in multiple ways. AS is prevalent in all eukaryotes including plants. AS generates two or more mRNAs from the precursor mRNA (pre-mRNA) to regulate transcriptome complexity and proteome diversity. Advances in next-generation sequencing, omics technology, bioinformatics tools, and computational methods provide new opportunities to quantify and visualize AS-based quantitative trait variation associated with plant growth, development, reproduction, and stress tolerance. Domestication, polyploidization, and environmental perturbation may evolve novel splicing variants associated with agronomically beneficial traits. To date, pre-mRNAs from many genes are spliced into multiple transcripts that cause phenotypic variation for complex traits, both in model plant Arabidopsis and field crops. Cataloguing and exploiting such variation may provide new paths to enhance climate resilience, resource-use efficiency, productivity, and nutritional quality of staple food crops. This review provides insights into AS variation alongside a gene expression analysis to select for novel phenotypic diversity for use in breeding programs. AS contributes to heterosis, enhances plant symbiosis (mycorrhiza and rhizobium), and provides a mechanistic link between the core clock genes and diverse environmental clues.
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Affiliation(s)
| | - Luis Felipe Quiroz
- Agriculture and Bioeconomy Research Centre, Ryan Institute, University of Galway, University Road, H91 REW4 Galway, Ireland
| | - Anireddy S N Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Charles Spillane
- Agriculture and Bioeconomy Research Centre, Ryan Institute, University of Galway, University Road, H91 REW4 Galway, Ireland
| | - Rodomiro Ortiz
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 23053 Alnarp, SE, Sweden
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Li Y, Sun W, Wang Z, Wan C, Zhang J, Qi X, Zhang J. SDG102, a H3K36-Methyltransferase-Encoding Gene, Plays Pleiotropic Roles in Growth and Development of Maize ( Zea mays L.). Int J Mol Sci 2022; 23:ijms23137458. [PMID: 35806471 PMCID: PMC9267571 DOI: 10.3390/ijms23137458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/01/2022] [Accepted: 07/02/2022] [Indexed: 02/01/2023] Open
Abstract
Although histone lysine methylation has been studied in thale cress (Arabidopsis thaliana (L.) Heynh.) and rice (Oryza sativa L.) in recent years, its function in maize (Zea mays L.) remains poorly characterized. To better understand the function of histone lysine methylation in maize, SDG102, a H3 lysine 36 (H3K36) methylase, was chosen for functional characterization using overexpressed and knockout transgenic plants. SDG102-deficiency in maize caused multiple phenotypes including yellow leaves in seedlings, late-flowering, and increased adult plant height, while the overexpression of SDG102 led to reduced adult plant height. The key flowering genes, ZCN8/ZCN7 and MADS4/MADA67, were downregulated in SDG102-deficient plants. Chromatin immunoprecipitation (ChIP) experiments showed that H3 lysine 36 trimethylation (H3K36me3) levels were reduced at these loci. Perturbation of SDG102 expression caused the misexpression of multiple genes. Interestingly, the overexpression or knockout of SDG102 also led to genome-wide decreases and increases in the H3K36me3 levels, respectively. Together, our results suggest that SDG102 is a methyltransferase that catalyzes the trimethylation of H3K36 of many genes across the maize genome, which are involved in multiple biological processes including those controlling flowering time.
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Affiliation(s)
- Yongjian Li
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
| | - Weifeng Sun
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
| | - Zhenhui Wang
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
| | - Chang Wan
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
| | - Jun Zhang
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
| | - Xin Qi
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
- Correspondence: (X.Q.); (J.Z.)
| | - Jian Zhang
- Faculty of Agronomy, Jilin Agricultural University, Changchun 130118, China; (Y.L.); (W.S.); (C.W.); (Z.W.); (J.Z.)
- Department of Biology, University of British Columbia, Okanagan, Kelowna, BC V1V 1V7, Canada
- Correspondence: (X.Q.); (J.Z.)
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4
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Hwarari D, Guan Y, Ahmad B, Movahedi A, Min T, Hao Z, Lu Y, Chen J, Yang L. ICE-CBF-COR Signaling Cascade and Its Regulation in Plants Responding to Cold Stress. Int J Mol Sci 2022; 23:ijms23031549. [PMID: 35163471 PMCID: PMC8835792 DOI: 10.3390/ijms23031549] [Citation(s) in RCA: 84] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/18/2022] [Accepted: 01/21/2022] [Indexed: 12/19/2022] Open
Abstract
Cold stress limits plant geographical distribution and influences plant growth, development, and yields. Plants as sessile organisms have evolved complex biochemical and physiological mechanisms to adapt to cold stress. These mechanisms are regulated by a series of transcription factors and proteins for efficient cold stress acclimation. It has been established that the ICE-CBF-COR signaling pathway in plants regulates how plants acclimatize to cold stress. Cold stress is perceived by receptor proteins, triggering signal transduction, and Inducer of CBF Expression (ICE) genes are activated and regulated, consequently upregulating the transcription and expression of the C-repeat Binding Factor (CBF) genes. The CBF protein binds to the C-repeat/Dehydration Responsive Element (CRT/DRE), a homeopathic element of the Cold Regulated genes (COR gene) promoter, activating their transcription. Transcriptional regulations and post-translational modifications regulate and modify these entities at different response levels by altering their expression or activities in the signaling cascade. These activities then lead to efficient cold stress tolerance. This paper contains a concise summary of the ICE-CBF-COR pathway elucidating on the cross interconnections with other repressors, inhibitors, and activators to induce cold stress acclimation in plants.
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Affiliation(s)
- Delight Hwarari
- College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; (D.H.); (Y.G.); (B.A.); (A.M.); (T.M.)
| | - Yuanlin Guan
- College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; (D.H.); (Y.G.); (B.A.); (A.M.); (T.M.)
| | - Baseer Ahmad
- College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; (D.H.); (Y.G.); (B.A.); (A.M.); (T.M.)
| | - Ali Movahedi
- College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; (D.H.); (Y.G.); (B.A.); (A.M.); (T.M.)
| | - Tian Min
- College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; (D.H.); (Y.G.); (B.A.); (A.M.); (T.M.)
| | - Zhaodong Hao
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China; (Z.H.); (Y.L.)
| | - Ye Lu
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China; (Z.H.); (Y.L.)
| | - Jinhui Chen
- College of Forestry, Nanjing Forestry University, Nanjing 210037, China; (Z.H.); (Y.L.)
- Correspondence: (J.C.); (L.Y.)
| | - Liming Yang
- College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; (D.H.); (Y.G.); (B.A.); (A.M.); (T.M.)
- Correspondence: (J.C.); (L.Y.)
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5
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Lohani N, Singh MB, Bhalla PL. Biological Parts for Engineering Abiotic Stress Tolerance in Plants. BIODESIGN RESEARCH 2022; 2022:9819314. [PMID: 37850130 PMCID: PMC10521667 DOI: 10.34133/2022/9819314] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 12/17/2021] [Indexed: 10/19/2023] Open
Abstract
It is vital to ramp up crop production dramatically by 2050 due to the increasing global population and demand for food. However, with the climate change projections showing that droughts and heatwaves becoming common in much of the globe, there is a severe threat of a sharp decline in crop yields. Thus, developing crop varieties with inbuilt genetic tolerance to environmental stresses is urgently needed. Selective breeding based on genetic diversity is not keeping up with the growing demand for food and feed. However, the emergence of contemporary plant genetic engineering, genome-editing, and synthetic biology offer precise tools for developing crops that can sustain productivity under stress conditions. Here, we summarize the systems biology-level understanding of regulatory pathways involved in perception, signalling, and protective processes activated in response to unfavourable environmental conditions. The potential role of noncoding RNAs in the regulation of abiotic stress responses has also been highlighted. Further, examples of imparting abiotic stress tolerance by genetic engineering are discussed. Additionally, we provide perspectives on the rational design of abiotic stress tolerance through synthetic biology and list various bioparts that can be used to design synthetic gene circuits whose stress-protective functions can be switched on/off in response to environmental cues.
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Affiliation(s)
- Neeta Lohani
- Plant Molecular Biology and Biotechnology Laboratory, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Mohan B. Singh
- Plant Molecular Biology and Biotechnology Laboratory, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Prem L. Bhalla
- Plant Molecular Biology and Biotechnology Laboratory, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
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6
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Jian Y, Shim WB, Ma Z. Multiple functions of SWI/SNF chromatin remodeling complex in plant-pathogen interactions. STRESS BIOLOGY 2021; 1:18. [PMID: 37676626 PMCID: PMC10442046 DOI: 10.1007/s44154-021-00019-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 11/22/2021] [Indexed: 09/08/2023]
Abstract
The SWI/SNF chromatin remodeling complex utilizes the energy of ATP hydrolysis to facilitate chromatin access and plays essential roles in DNA-based events. Studies in animals, plants and fungi have uncovered sophisticated regulatory mechanisms of this complex that govern development and various stress responses. In this review, we summarize the composition of SWI/SNF complex in eukaryotes and discuss multiple functions of the SWI/SNF complex in regulating gene transcription, mRNA splicing, and DNA damage response. Our review further highlights the importance of SWI/SNF complex in regulating plant immunity responses and fungal pathogenesis. Finally, the potentials in exploiting chromatin remodeling for management of crop disease are presented.
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Affiliation(s)
- Yunqing Jian
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Won-Bo Shim
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| | - Zhonghua Ma
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, China.
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7
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Rashid MM, Vaishnav A, Verma RK, Sharma P, Suprasanna P, Gaur RK. Epigenetic regulation of salinity stress responses in cereals. Mol Biol Rep 2021; 49:761-772. [PMID: 34773178 DOI: 10.1007/s11033-021-06922-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/30/2021] [Indexed: 10/19/2022]
Abstract
Cereals are important crops and are exposed to various types of environmental stresses that affect the overall growth and yield. Among the various abiotic stresses, salt stress is a major environmental factor that influences the genetic, physiological, and biochemical responses of cereal crops. Epigenetic regulation which includes DNA methylation, histone modification, and chromatin remodelling plays an important role in salt stress tolerance. Recent studies in rice genomics have highlighted that the epigenetic changes are heritable and therefore can be considered as molecular signatures. An epigenetic mechanism under salinity induces phenotypic responses involving modulations in gene expression. Association between histone modification and altered DNA methylation patterns and differential gene expression has been evidenced for salt sensitivity in rice and other cereal crops. In addition, epigenetics also creates stress memory that helps the plant to better combat future stress exposure. In the present review, we have discussed epigenetic influences in stress tolerance, adaptation, and evolution processes. Understanding the epigenetic regulation of salinity could help for designing salt-tolerant varieties leading to improved crop productivity.
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Affiliation(s)
- Md Mahtab Rashid
- Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.,Department of Plant Pathology, Bihar Agricultural University, Sabour, Bhagalpur, Bihar, India
| | - Anukool Vaishnav
- Department of Biotechnology, GLA University, Mathura, Uttar Pradesh, 281121, India.,Agroecology and Environment, Agroscope (Reckenholz), 8046, Zürich, Switzerland
| | - Rakesh Kumar Verma
- Department of Biosciences, Mody University of Science and Technology, Lakshmangarh, Sikar, Rajasthan, India
| | - Pradeep Sharma
- Department of Biotechnology, ICAR-Indian Institute of Wheat and Barley Research, Karnal, Haryana, India
| | - P Suprasanna
- Nuclear Agriculture & Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
| | - R K Gaur
- Department of Biotechnology, Deen Dayal Upadhyay Gorakhpur University, Gorakhpur, Uttar Pradesh, India.
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8
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Alternative splicing in plant abiotic stress responses. Biochem Soc Trans 2021; 48:2117-2126. [PMID: 32869832 DOI: 10.1042/bst20200281] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/05/2020] [Accepted: 08/07/2020] [Indexed: 02/06/2023]
Abstract
Modifications of the cellular proteome pool upon stress allow plants to tolerate environmental changes. Alternative splicing is the most significant mechanism responsible for the production of multiple protein isoforms from a single gene. The spliceosome, a large ribonucleoprotein complex, together with several associated proteins, controls this pre-mRNA processing, adding an additional level of regulation to gene expression. Deep sequencing of transcriptomes revealed that this co- or post-transcriptional mechanism is highly induced by abiotic stress, and concerns vast numbers of stress-related genes. Confirming the importance of splicing in plant stress adaptation, key players of stress signaling have been shown to encode alternative transcripts, whereas mutants lacking splicing factors or associated components show a modified sensitivity and defective responses to abiotic stress. Here, we examine recent literature on alternative splicing and splicing alterations in response to environmental stresses, focusing on its role in stress adaptation and analyzing the future perspectives and directions for research.
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9
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Decoding co-/post-transcriptional complexities of plant transcriptomes and epitranscriptome using next-generation sequencing technologies. Biochem Soc Trans 2021; 48:2399-2414. [PMID: 33196096 DOI: 10.1042/bst20190492] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/06/2020] [Accepted: 10/22/2020] [Indexed: 12/12/2022]
Abstract
Next-generation sequencing (NGS) technologies - Illumina RNA-seq, Pacific Biosciences isoform sequencing (PacBio Iso-seq), and Oxford Nanopore direct RNA sequencing (DRS) - have revealed the complexity of plant transcriptomes and their regulation at the co-/post-transcriptional level. Global analysis of mature mRNAs, transcripts from nuclear run-on assays, and nascent chromatin-bound mRNAs using short as well as full-length and single-molecule DRS reads have uncovered potential roles of different forms of RNA polymerase II during the transcription process, and the extent of co-transcriptional pre-mRNA splicing and polyadenylation. These tools have also allowed mapping of transcriptome-wide start sites in cap-containing RNAs, poly(A) site choice, poly(A) tail length, and RNA base modifications. The emerging theme from recent studies is that reprogramming of gene expression in response to developmental cues and stresses at the co-/post-transcriptional level likely plays a crucial role in eliciting appropriate responses for optimal growth and plant survival under adverse conditions. Although the mechanisms by which developmental cues and different stresses regulate co-/post-transcriptional splicing are largely unknown, a few recent studies indicate that the external cues target spliceosomal and splicing regulatory proteins to modulate alternative splicing. In this review, we provide an overview of recent discoveries on the dynamics and complexities of plant transcriptomes, mechanistic insights into splicing regulation, and discuss critical gaps in co-/post-transcriptional research that need to be addressed using diverse genomic and biochemical approaches.
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10
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Yu H, Du Q, Campbell M, Yu B, Walia H, Zhang C. Genome-wide discovery of natural variation in pre-mRNA splicing and prioritising causal alternative splicing to salt stress response in rice. THE NEW PHYTOLOGIST 2021; 230:1273-1287. [PMID: 33453070 PMCID: PMC8048671 DOI: 10.1111/nph.17189] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/04/2021] [Indexed: 05/14/2023]
Abstract
Pre-mRNA splicing is an essential step for the regulation of gene expression. In order to specifically capture splicing variants in plants for genome-wide association studies (GWAS), we developed a software tool to quantify and visualise Variations of Splicing in Population (VaSP). VaSP can quantify splicing variants from short-read RNA-seq datasets and discover genotype-specific splicing (GSS) events, which can be used to prioritise causal pre-mRNA splicing events in GWAS. We applied our method to an RNA-seq dataset with 328 samples from 82 genotypes from a rice diversity panel exposed to optimal and saline growing conditions. In total, 764 significant GSS events were identified in salt stress conditions. GSS events were used as markers for a GWAS with the shoot Na+ accumulation, which identified six GSS events in five genes significantly associated with the shoot Na+ content. Two of these genes, OsNUC1 and OsRAD23 emerged as top candidate genes with splice variants that exhibited significant divergence between the variants for shoot growth under salt stress conditions. VaSP is a versatile tool for alternative splicing analysis in plants and a powerful tool for prioritising candidate causal pre-mRNA splicing and corresponding genomic variations in GWAS.
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Affiliation(s)
- Huihui Yu
- School of Biological SciencesUniversity of NebraskaLincolnNE68588USA
| | - Qian Du
- School of Biological SciencesUniversity of NebraskaLincolnNE68588USA
| | - Malachy Campbell
- Department of Agronomy and HorticultureUniversity of NebraskaLincolnNE68583USA
- Department of Plant BiologyCornell UniversityIthacaNY14850USA
| | - Bin Yu
- School of Biological SciencesUniversity of NebraskaLincolnNE68588USA
- Center for Plant Science and InnovationUniversity of NebraskaLincolnNE68588USA
| | - Harkamal Walia
- Department of Agronomy and HorticultureUniversity of NebraskaLincolnNE68583USA
- Center for Plant Science and InnovationUniversity of NebraskaLincolnNE68588USA
| | - Chi Zhang
- School of Biological SciencesUniversity of NebraskaLincolnNE68588USA
- Center for Plant Science and InnovationUniversity of NebraskaLincolnNE68588USA
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Ganie SA, Reddy ASN. Stress-Induced Changes in Alternative Splicing Landscape in Rice: Functional Significance of Splice Isoforms in Stress Tolerance. BIOLOGY 2021; 10:309. [PMID: 33917813 PMCID: PMC8068108 DOI: 10.3390/biology10040309] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 04/01/2021] [Accepted: 04/06/2021] [Indexed: 12/20/2022]
Abstract
Improvements in yield and quality of rice are crucial for global food security. However, global rice production is substantially hindered by various biotic and abiotic stresses. Making further improvements in rice yield is a major challenge to the rice research community, which can be accomplished through developing abiotic stress-resilient rice varieties and engineering durable agrochemical-independent pathogen resistance in high-yielding elite rice varieties. This, in turn, needs increased understanding of the mechanisms by which stresses affect rice growth and development. Alternative splicing (AS), a post-transcriptional gene regulatory mechanism, allows rapid changes in the transcriptome and can generate novel regulatory mechanisms to confer plasticity to plant growth and development. Mounting evidence indicates that AS has a prominent role in regulating rice growth and development under stress conditions. Several regulatory and structural genes and splicing factors of rice undergo different types of stress-induced AS events, and the functional significance of some of them in stress tolerance has been defined. Both rice and its pathogens use this complex regulatory mechanism to devise strategies against each other. This review covers the current understanding and evidence for the involvement of AS in biotic and abiotic stress-responsive genes, and its relevance to rice growth and development. Furthermore, we discuss implications of AS for the virulence of different rice pathogens and highlight the areas of further research and potential future avenues to develop climate-smart and disease-resistant rice varieties.
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Affiliation(s)
| | - Anireddy S. N. Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
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12
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Song ZT, Liu JX, Han JJ. Chromatin remodeling factors regulate environmental stress responses in plants. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:438-450. [PMID: 33421288 DOI: 10.1111/jipb.13064] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 12/23/2020] [Indexed: 05/14/2023]
Abstract
Environmental stress from climate change and agricultural activity threatens global plant biodiversity as well as crop yield and quality. As sessile organisms, plants must maintain the integrity of their genomes and adjust gene expression to adapt to various environmental changes. In eukaryotes, nucleosomes are the basic unit of chromatin around which genomic DNA is packaged by condensation. To enable dynamic access to packaged DNA, eukaryotes have evolved Snf2 (sucrose nonfermenting 2) family proteins as chromatin remodeling factors (CHRs) that modulate the position of nucleosomes on chromatin. During plant stress responses, CHRs are recruited to specific genomic loci, where they regulate the distribution or composition of nucleosomes, which in turn alters the accessibility of these loci to general transcription or DNA damage repair machinery. Moreover, CHRs interplay with other epigenetic mechanisms, including DNA methylation, histone modifications, and deposition of histone variants. CHRs are also involved in RNA processing at the post-transcriptional level. In this review, we discuss major advances in our understanding of the mechanisms by which CHRs function during plants' response to environmental stress.
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Affiliation(s)
- Ze-Ting Song
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, 650500, China
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310027, China
| | - Jian-Xiang Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310027, China
| | - Jia-Jia Han
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, 650500, China
- Laboratory of Ecology and Evolutionary Biology, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, 650500, China
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13
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Li A, Hu B, Chu C. Epigenetic regulation of nitrogen and phosphorus responses in plants. JOURNAL OF PLANT PHYSIOLOGY 2021; 258-259:153363. [PMID: 33508741 DOI: 10.1016/j.jplph.2021.153363] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/31/2020] [Accepted: 01/01/2021] [Indexed: 05/18/2023]
Abstract
Nitrogen (N) and phosphorus (P) are two of the most important nutrients for plant growth and crop yields. In the last decade, plenty of studies have revealed the genetic factors and their regulatory networks which are involved in N and/or P uptake and utilization in different model plant species, especially in Arabidopsis and rice. However, increasing evidences have shown that epigenetic regulation also plays a vital role in modulating plant responses to nutrient availability. In this review, we make a brief summary of epigenetic regulation including histone modifications, DNA methylation, and other chromatin structure alterations in tuning N and P responses. We also give an outlook for future research directions to comprehensively dissect the involvement of epigenetic regulation in modulating nutrient response in plants.
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Affiliation(s)
- Aifu Li
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin Hu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Chengcai Chu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
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14
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Jabre I, Chaudhary S, Guo W, Kalyna M, Reddy ASN, Chen W, Zhang R, Wilson C, Syed NH. Differential nucleosome occupancy modulates alternative splicing in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2021; 229:1937-1945. [PMID: 33135169 DOI: 10.1111/nph.17062] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/24/2020] [Indexed: 05/13/2023]
Abstract
Alternative splicing (AS) is a major gene regulatory mechanism in plants. Recent evidence supports co-transcriptional splicing in plants, hence the chromatin state can impact AS. However, how dynamic changes in the chromatin state such as nucleosome occupancy influence the cold-induced AS remains poorly understood. Here, we generated transcriptome (RNA-Seq) and nucleosome positioning (MNase-Seq) data for Arabidopsis thaliana to understand how nucleosome positioning modulates cold-induced AS. Our results show that characteristic nucleosome occupancy levels are strongly associated with the type and abundance of various AS events under normal and cold temperature conditions in Arabidopsis. Intriguingly, exitrons, alternatively spliced internal regions of protein-coding exons, exhibit distinctive nucleosome positioning pattern compared to other alternatively spliced regions. Likewise, nucleosome patterns differ between exitrons and retained introns, pointing to their distinct regulation. Collectively, our data show that characteristic changes in nucleosome positioning modulate AS in plants in response to cold.
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Affiliation(s)
- Ibtissam Jabre
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
- School of Biosciences and Medicine, University of Surrey, Guildford, GU2 7XH, UK
| | - Saurabh Chaudhary
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
- Cardiff School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK
| | - Wenbin Guo
- Computational Sciences, The James Hutton Institute, Dundee, DD2 5DA, UK
| | - Maria Kalyna
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences - BOKU, Muthgasse 18, 1190, Vienna, Austria
| | - Anireddy S N Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, 80523-1878, USA
| | - Weizhong Chen
- Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, 14853-2703, USA
| | - Runxuan Zhang
- Computational Sciences, The James Hutton Institute, Dundee, DD2 5DA, UK
| | - Cornelia Wilson
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Naeem H Syed
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
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15
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Agirre E, Oldfield AJ, Bellora N, Segelle A, Luco RF. Splicing-associated chromatin signatures: a combinatorial and position-dependent role for histone marks in splicing definition. Nat Commun 2021; 12:682. [PMID: 33514745 PMCID: PMC7846797 DOI: 10.1038/s41467-021-20979-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 01/05/2021] [Indexed: 12/14/2022] Open
Abstract
Alternative splicing relies on the combinatorial recruitment of splicing regulators to specific RNA binding sites. Chromatin has been shown to impact this recruitment. However, a limited number of histone marks have been studied at a global level. In this work, a machine learning approach, applied to extensive epigenomics datasets in human H1 embryonic stem cells and IMR90 foetal fibroblasts, has identified eleven chromatin modifications that differentially mark alternatively spliced exons depending on the level of exon inclusion. These marks act in a combinatorial and position-dependent way, creating characteristic splicing-associated chromatin signatures (SACS). In support of a functional role for SACS in coordinating splicing regulation, changes in the alternative splicing of SACS-marked exons between ten different cell lines correlate with changes in SACS enrichment levels and recruitment of the splicing regulators predicted by RNA motif search analysis. We propose the dynamic nature of chromatin modifications as a mechanism to rapidly fine-tune alternative splicing when necessary. Chromatin is known to regulate splicing by modulating recruitment of splicing factors. Using machine learning approaches, the authors have underlined a chromatin code for alternative splicing regulation that is conserved amongst cell lines.
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Affiliation(s)
- E Agirre
- Institute of Human Genetics, UMR9002 CNRS-University of Montpellier, 34000, Montpellier, France.,Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - A J Oldfield
- Institute of Human Genetics, UMR9002 CNRS-University of Montpellier, 34000, Montpellier, France
| | - N Bellora
- Institute of Nuclear Technologies for Health (INTECNUS), National Scientific and Technical Research Council (CONICET), Bariloche, 8400, Argentina
| | - A Segelle
- Institute of Human Genetics, UMR9002 CNRS-University of Montpellier, 34000, Montpellier, France
| | - R F Luco
- Institute of Human Genetics, UMR9002 CNRS-University of Montpellier, 34000, Montpellier, France.
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16
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Qi D, Wen Q, Meng Z, Yuan S, Guo H, Zhao H, Cui S. OsLFR is essential for early endosperm and embryo development by interacting with SWI/SNF complex members in Oryza sativa. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:901-916. [PMID: 32808364 DOI: 10.1111/tpj.14967] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 07/09/2020] [Accepted: 07/29/2020] [Indexed: 05/26/2023]
Abstract
Rice (Oryza sativa L.) endosperm provides the developing embryo with nutrients and provides human beings with a staple food. The embryo eventually develops into a new sporophyte generation. Despite their important roles, the molecular mechanisms underlying early-stage endosperm and embryo development remain elusive. Here, we established the fundamental functions of rice OsLFR, an ortholog of the Arabidopsis SWI/SNF chromatin-remodeling complex (CRC) component LFR. OsLFR was expressed primarily in the rice spikelets and seeds, and the OsLFR protein was localized to the nucleus. We conducted genetic, cellular and molecular analyses of loss-of-function mutants and transgenic rescue lines. OsLFR depletion resulted in homozygous lethality in the early seed stage through endosperm and embryo defects, which could be successfully recovered by the OsLFR genomic sequence. Cytological observations revealed that the oslfr endosperm had relatively fewer free nuclei, had abnormal and arrested cellularization, and demonstrated premature programed cell death: the embryo was reduced in size and failed to differentiate. Transcriptome profiling showed that many genes, involved in DNA replication, cell cycle, cell wall assembly and cell death, were differentially expressed in a knockout mutant of OsLFR (oslfr-1), which was consistent with the observed seed defects. Protein-protein interaction analysis showed that OsLFR physically interacts with several putative rice SWI/SNF CRC components. Our findings demonstrate that OsLFR, possibly as one component of the SWI/SNF CRC, is an essential regulator of rice seed development, and provide further insights into the regulatory mechanism of early-stage rice endosperm and embryo development.
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Affiliation(s)
- Dongmei Qi
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
| | - Qingqing Wen
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
| | - Ze Meng
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
| | - Shan Yuan
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
| | - Hong Guo
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
| | - Hongtao Zhao
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
| | - Sujuan Cui
- Hebei Key Laboratory of Molecular and Cellular Biology, Hebei Normal University, Hebei, 050024, China
- Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Normal University, Hebei, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Hebei, 050024, China
- College of Life Science, Hebei Normal University, Hebei, 050024, China
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17
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Zhang J, Zhang YZ, Jiang J, Duan CG. The Crosstalk Between Epigenetic Mechanisms and Alternative RNA Processing Regulation. Front Genet 2020; 11:998. [PMID: 32973889 PMCID: PMC7472560 DOI: 10.3389/fgene.2020.00998] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 08/05/2020] [Indexed: 12/19/2022] Open
Abstract
As a co-transcriptional process, RNA processing, including alternative splicing and alternative polyadenylation, is crucial for the generation of multiple mRNA isoforms. RNA processing mechanisms are widespread across all higher eukaryotes and play critical roles in cell differentiation, organ development and disease response. Recently, significant progresses have been made in understanding the mechanism of RNA processing. RNA processing is regulated by trans-acting factors such as splicing factors, RNA-binding proteins and cis-sequences in pre-mRNA, and increasing evidence suggests that epigenetic mechanisms, which are important for the dynamic regulation and state of specific chromatic regions, are also involved in co-transcriptional RNA processing. In contrast, recent studies also suggest that alternative RNA processing also has a feedback regulation on epigenetic mechanisms. In this review, we discuss recent studies and summarize the current knowledge on the epigenetic regulation of alternative RNA processing. In addition, a feedback regulation of RNA processing on epigenetic regulators is also discussed.
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Affiliation(s)
- Jian Zhang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yi-Zhe Zhang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jing Jiang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Cheng-Guo Duan
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China.,State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
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18
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Tognacca RS, Kubaczka MG, Servi L, Rodríguez FS, Godoy Herz MA, Petrillo E. Light in the transcription landscape: chromatin, RNA polymerase II and splicing throughout Arabidopsis thaliana's life cycle. Transcription 2020; 11:117-133. [PMID: 32748694 DOI: 10.1080/21541264.2020.1796473] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Plants have a high level of developmental plasticity that allows them to respond and adapt to changes in the environment. Among the environmental cues, light controls almost every aspect of A. thaliana's life cycle, including seed maturation, seed germination, seedling de-etiolation and flowering time. Light signals induce massive reprogramming of gene expression, producing changes in RNA polymerase II transcription, alternative splicing, and chromatin state. Since splicing reactions occur mainly while transcription takes place, the regulation of RNAPII transcription has repercussions in the splicing outcomes. This cotranscriptional nature allows a functional coupling between transcription and splicing, in which properties of the splicing reactions are affected by the transcriptional process. Chromatin landscapes influence both transcription and splicing. In this review, we highlight, summarize and discuss recent progress in the field to gain a comprehensive insight on the cross-regulation between chromatin state, RNAPII transcription and splicing decisions in plants, with a special focus on light-triggered responses. We also introduce several examples of transcription and splicing factors that could be acting as coupling factors in plants. Unravelling how these connected regulatory networks operate, can help in the design of better crops with higher productivity and tolerance.
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Affiliation(s)
- Rocío S Tognacca
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina.,Instituto De Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), CONICET-Universidad De Buenos Aires , Buenos Aires, Argentina
| | - M Guillermina Kubaczka
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina.,Instituto De Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), CONICET-Universidad De Buenos Aires , Buenos Aires, Argentina
| | - Lucas Servi
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina.,Instituto De Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), CONICET-Universidad De Buenos Aires , Buenos Aires, Argentina
| | - Florencia S Rodríguez
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina.,Instituto De Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), CONICET-Universidad De Buenos Aires , Buenos Aires, Argentina.,Departamento De Biodiversidad Y Biología Experimental, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina
| | - Micaela A Godoy Herz
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina.,Instituto De Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), CONICET-Universidad De Buenos Aires , Buenos Aires, Argentina
| | - Ezequiel Petrillo
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires , Buenos Aires, Argentina.,Instituto De Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), CONICET-Universidad De Buenos Aires , Buenos Aires, Argentina
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19
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Meng X, Yu X, Wu Y, Kim DH, Nan N, Cong W, Wang S, Liu B, Xu ZY. Chromatin Remodeling Protein ZmCHB101 Regulates Nitrate-Responsive Gene Expression in Maize. FRONTIERS IN PLANT SCIENCE 2020; 11:52. [PMID: 32117389 PMCID: PMC7031486 DOI: 10.3389/fpls.2020.00052] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 01/15/2020] [Indexed: 05/24/2023]
Abstract
Nitrate is the main source of nitrogen for plants and an essential component of fertilizers. Rapid transcriptional activation of genes encoding the high-affinity nitrate transport system (HATS) is an important strategy that plants use to cope with nitrogen deficiency. However, the specific transcriptional machineries involved in this process and the detailed transcriptional regulatory mechanism of the core HATS remain poorly understood. ZmCHB101 is the core subunit of the SWI/SNF-type ATP-dependent chromatin remodeling complex in maize. RNA-interference transgenic plants (ZmCHB101-RNAi) display abaxially curling leaves and impaired tassel and cob development. Here, we demonstrate that ZmCHB101 plays a pivotal regulatory role in nitrate-responsive gene expression. ZmCHB101-RNAi lines showed accelerated root growth and increased biomass under low nitrate conditions. An RNA sequencing analysis revealed that ZmCHB101 regulates the expression of genes involved in nitrate transport, including ZmNRT2.1 and ZmNRT2.2. The NIN-like protein (NLP) of maize, ZmNLP3.1, recognized the consensus nitrate-responsive cis-elements (NREs) in the promoter regions of ZmNRT2.1 and ZmNRT2.2, and activated the transcription of these genes in response to nitrate. Intriguingly, well-positioned nucleosomes were detected at NREs in the ZmNRT2.1 and ZmNRT2.2 gene promoters, and nucleosome densities were lower in ZmCHB101-RNAi lines than in wild-type plants, both in the absence and presence of nitrate. The ZmCHB101 protein bound to NREs and was involved in the maintenance of nucleosome occupancies at these sites, which may impact the binding of ZmNLP3.1 to NREs in the absence of nitrate. However, in the presence of nitrate, the binding affinity of ZmCHB101 for NREs decreased dramatically, leading to reduced nucleosome density at NREs and consequently increased ZmNLP3.1 binding. Our results provide novel insights into the role of chromatin remodeling proteins in the regulation of nitrate-responsive gene expression in plants.
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Affiliation(s)
- Xinchao Meng
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Xiaoming Yu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
- School of Agronomy, Jilin Agricultural Science and Technology University, Jilin, China
| | - Yifan Wu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Dae Heon Kim
- Department of Biology, Sunchon National University, Sunchon, South Korea
| | - Nan Nan
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Weixuan Cong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Shucai Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
- College of Life Sciences, Linyi University, Linyi, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Zheng-Yi Xu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
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