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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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2
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Rodriguez Gallo MC, Uhrig RG. Phosphorylation mediated regulation of RNA splicing in plants. FRONTIERS IN PLANT SCIENCE 2023; 14:1249057. [PMID: 37780493 PMCID: PMC10539000 DOI: 10.3389/fpls.2023.1249057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 08/22/2023] [Indexed: 10/03/2023]
Abstract
For the past two decades, the study of alternative splicing (AS) and its involvement in plant development and stress response has grown in popularity. Only recently however, has the focus shifted to the study of how AS regulation (or lack-thereof) affects downstream mRNA and protein landscapes and how these AS regulatory events impact plant development and stress tolerance. In humans, protein phosphorylation represents one of the predominant mechanisms by which AS is regulated and thus the protein kinases governing these phosphorylation events are of interest for further study. Large-scale phosphoproteomic studies in plants have consistently found that RNA splicing-related proteins are extensively phosphorylated, however, the signaling pathways involved in AS regulation have not been resolved. In this mini-review, we summarize our current knowledge of the three major splicing-related protein kinase families in plants that are suggested to mediate AS phospho-regulation and draw comparisons to their metazoan orthologs. We also summarize and contextualize the phosphorylation events identified as occurring on splicing-related protein families to illustrate the high degree to which splicing-related proteins are modified, placing a new focus on elucidating the impacts of AS at the protein and PTM-level.
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Affiliation(s)
| | - R. Glen Uhrig
- University of Alberta, Department of Biological Sciences, Edmonton, AB, Canada
- University of Alberta, Department of Biochemistry, Edmonton, AB, Canada
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3
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Hussain SS, Abbas M, Abbas S, Wei M, El-Sappah AH, Sun Y, Li Y, Ragauskas AJ, Li Q. Alternative splicing: transcriptional regulatory network in agroforestry. FRONTIERS IN PLANT SCIENCE 2023; 14:1158965. [PMID: 37123829 PMCID: PMC10132464 DOI: 10.3389/fpls.2023.1158965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 03/13/2023] [Indexed: 05/03/2023]
Abstract
Alternative splicing (AS) in plants plays a key role in regulating the expression of numerous transcripts from a single gene in a regulatory pathway. Variable concentrations of growth regulatory hormones and external stimuli trigger alternative splicing to switch among different growth stages and adapt to environmental stresses. In the AS phenomenon, a spliceosome causes differential transcriptional modifications in messenger RNA (mRNAs), resulting in partial or complete retention of one or more introns as compared to fully spliced mRNA. Differentially expressed proteins translated from intron-retaining messenger RNA (mRNAir) perform vital functions in the feedback mechanism. At the post-transcriptional level, AS causes the remodeling of transcription factors (TFs) by the addition or deletion of binding domains to activate and/or repress transcription. In this study, we have summarized the specific role of AS in the regulation of gene expression through repression and activation of the transcriptional regulatory network under external stimuli and switch among developmental stages.
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Affiliation(s)
- Syed Sarfaraz Hussain
- State Key Laboratory of Tree Genetics and Breeding, Engineering Technology Research Center of Black Locust of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Manzar Abbas
- Faculty of Agriculture, Forestry and Food Engineering, Yibin University, Yibin, Sichuan, China
| | - Sammar Abbas
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, China
| | - Mingke Wei
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Ahmed H. El-Sappah
- Faculty of Agriculture, Forestry and Food Engineering, Yibin University, Yibin, Sichuan, China
- Genetics Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Yuhan Sun
- State Key Laboratory of Tree Genetics and Breeding, Engineering Technology Research Center of Black Locust of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Yun Li
- State Key Laboratory of Tree Genetics and Breeding, Engineering Technology Research Center of Black Locust of National Forestry and Grassland Administration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- *Correspondence: Yun Li, ; Arthur J. Ragauskas, ; Quanzi Li,
| | - Arthur J. Ragauskas
- Department of Forestry, Wildlife, and Fisheries, Center for Renewable Carbon, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
- Joint Institute for Biological Science, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
- Department of Chemical and Biomolecular Engineering, The University of Tennessee-Knoxville, Knoxville, TN, United States
- *Correspondence: Yun Li, ; Arthur J. Ragauskas, ; Quanzi Li,
| | - Quanzi Li
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
- *Correspondence: Yun Li, ; Arthur J. Ragauskas, ; Quanzi Li,
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Lan W, Qiu Y, Xu Y, Liu Y, Miao Y. Ubiquitination and Ubiquitin-Like Modifications as Mediators of Alternative Pre-mRNA Splicing in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 13:869870. [PMID: 35646014 PMCID: PMC9134077 DOI: 10.3389/fpls.2022.869870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 04/07/2022] [Indexed: 06/15/2023]
Abstract
Alternative splicing (AS) is a common post-transcriptional regulatory process in eukaryotes. AS has an irreplaceable role during plant development and in response to environmental stress as it evokes differential expression of downstream genes or splicing factors (e.g., serine/arginine-rich proteins). Numerous studies have reported that loss of AS capacity leads to defects in plant growth and development, and induction of stress-sensitive phenotypes. A role for post-translational modification (PTM) of AS components has emerged in recent years. These modifications are capable of regulating the activity, stability, localization, interaction, and folding of spliceosomal proteins in human cells and yeast, indicating that PTMs represent another layer of AS regulation. In this review, we summarize the recent reports concerning ubiquitin and ubiquitin-like modification of spliceosome components and analyze the relationship between spliceosome and the ubiquitin/26S proteasome pathway in plants. Based on the totality of the evidence presented, we further speculate on the roles of protein ubiquitination mediated AS in plant development and environmental response.
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Temperature-Dependent Alternative Splicing of Precursor mRNAs and Its Biological Significance: A Review Focused on Post-Transcriptional Regulation of a Cold Shock Protein Gene in Hibernating Mammals. Int J Mol Sci 2020; 21:ijms21207599. [PMID: 33066638 PMCID: PMC7590145 DOI: 10.3390/ijms21207599] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 01/18/2023] Open
Abstract
Multiple mRNA isoforms are often generated during processing such as alternative splicing of precursor mRNAs (pre-mRNA), resulting in a diversity of generated proteins. Alternative splicing is an essential mechanism for the functional complexity of eukaryotes. Temperature, which is involved in all life activities at various levels, is one of regulatory factors for controlling patterns of alternative splicing. Temperature-dependent alternative splicing is associated with various phenotypes such as flowering and circadian clock in plants and sex determination in poikilothermic animals. In some specific situations, temperature-dependent alternative splicing can be evoked even in homothermal animals. For example, the splicing pattern of mRNA for a cold shock protein, cold-inducible RNA-binding protein (CIRP or CIRBP), is changed in response to a marked drop in body temperature during hibernation of hamsters. In this review, we describe the current knowledge about mechanisms and functions of temperature-dependent alternative splicing in plants and animals. Then we discuss the physiological significance of hypothermia-induced alternative splicing of a cold shock protein gene in hibernating and non-hibernating animals.
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7
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Sullivan A, Purohit PK, Freese NH, Pasha A, Esteban E, Waese J, Wu A, Chen M, Chin CY, Song R, Watharkar SR, Chan AP, Krishnakumar V, Vaughn MW, Town C, Loraine AE, Provart NJ. An 'eFP-Seq Browser' for visualizing and exploring RNA sequencing data. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 100:641-654. [PMID: 31350781 PMCID: PMC6899666 DOI: 10.1111/tpj.14468] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/25/2019] [Accepted: 07/02/2019] [Indexed: 05/10/2023]
Abstract
Improvements in next-generation sequencing technologies have resulted in dramatically reduced sequencing costs. This has led to an explosion of '-seq'-based methods, of which RNA sequencing (RNA-seq) for generating transcriptomic data is the most popular. By analysing global patterns of gene expression in organs/tissues/cells of interest or in response to chemical or environmental perturbations, researchers can better understand an organism's biology. Tools designed to work with large RNA-seq data sets enable analyses and visualizations to help generate hypotheses about a gene's function. We present here a user-friendly RNA-seq data exploration tool, called the 'eFP-Seq Browser', that shows the read map coverage of a gene of interest in each of the samples along with 'electronic fluorescent pictographic' (eFP) images that serve as visual representations of expression levels. The tool also summarizes the details of each RNA-seq experiment, providing links to archival databases and publications. It automatically computes the reads per kilobase per million reads mapped expression-level summaries and point biserial correlation scores to sort the samples based on a gene's expression level or by how dissimilar the read map profile is from a gene splice variant, to quickly identify samples with the strongest expression level or where alternative splicing might be occurring. Links to the Integrated Genome Browser desktop visualization tool allow researchers to visualize and explore the details of RNA-seq alignments summarized in eFP-Seq Browser as coverage graphs. We present four cases of use of the eFP-Seq Browser for ABI3, SR34, SR45a and U2AF65B, where we examine expression levels and identify alternative splicing. The URL for the browser is https://bar.utoronto.ca/eFP-Seq_Browser/. OPEN RESEARCH BADGES: This article has earned an Open Data Badge for making publicly available the digitally-shareable data necessary to reproduce the reported results. Tool is at https://bar.utoronto.ca/eFP-Seq_Browser/; RNA-seq data at https://s3.amazonaws.com/iplant-cdn/iplant/home/araport/rnaseq_bam/ and https://s3.amazonaws.com/iplant-cdn/iplant/home/araport/rnaseq_bam/Klepikova/. Code is available at https://github.com/BioAnalyticResource/eFP-Seq-Browser.
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Affiliation(s)
- Alexander Sullivan
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Priyank K. Purohit
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | | | - Asher Pasha
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Eddi Esteban
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Jamie Waese
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Alison Wu
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Michelle Chen
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Chih Y. Chin
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | - Richard Song
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
| | | | | | | | - Matthew W. Vaughn
- Texas Advanced Computing CenterUniversity of Texas at AustinAustinTXUSA
| | | | | | - Nicholas J. Provart
- Department of Cell and Systems Biology/CAGEFUniversity of TorontoTorontoONCanada
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8
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Genome-Wide Analysis of Serine/Arginine-Rich Protein Family in Wheat and Brachypodium distachyon. PLANTS 2019; 8:plants8070188. [PMID: 31247888 PMCID: PMC6681277 DOI: 10.3390/plants8070188] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/20/2019] [Accepted: 06/22/2019] [Indexed: 12/15/2022]
Abstract
By regulating the pre-mRNA splicing of other genes and themselves, plant serine/arginine-rich (SR) proteins play important roles in development and in response to abiotic stresses. Presently, the functions of most plant SR protein genes remain unclear. Wheat (Triticumaestivum) and Brachypodiumdistachyon are closely related species. In this study, 40 TaSR and 18 BdSR proteins were identified respectively, and they were classified into seven subfamilies: SR, RS, SCL, RSZ, RS2Z, SC35, and SR45. Similar to Arabidopsis and rice SR protein genes, most TaSR and BdSR protein genes are expressed extensively. Surprisingly, real-time polymerase chain reaction (RT-PCR) analyses showed that no alternative splicing event was found in TaSR protein genes, and only six BdSR protein genes are alternatively spliced genes. The detected alternatively spliced BdSR protein genes and transcripts are much fewer than in Arabidopsis, rice, maize, and sorghum. In the promoter regions, 92 development-related, stress-related, and hormone-related cis-elements were detected, indicating their functions in development and in response to environmental stresses. Meanwhile, 19 TaSR and 16 BdSR proteins were predicted to interact with other SR proteins or non-SR proteins, implying that they are involved in other functions in addition to modulating pre-mRNA splicing as essential components of the spliceosome. These results lay a foundation for further analyses of these genes.
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9
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Lee CC, Chang WH, Chang YS, Yang JM, Chang CS, Hsu KC, Chen YT, Liu TY, Chen YC, Lin SY, Wu YC, Chang JG. Alternative splicing in human cancer cells is modulated by the amiloride derivative 3,5-diamino-6-chloro-N-(N-(2,6-dichlorobenzoyl)carbamimidoyl)pyrazine-2-carboxide. Mol Oncol 2019; 13:1744-1762. [PMID: 31152681 PMCID: PMC6670021 DOI: 10.1002/1878-0261.12524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 04/30/2019] [Accepted: 05/30/2019] [Indexed: 12/11/2022] Open
Abstract
Alternative splicing (AS) is a process that enables the generation of multiple protein isoforms with different biological properties from a single mRNA. Cancer cells often use the maneuverability conferred by AS to produce proteins that contribute to growth and survival. In our previous studies, we identified that amiloride modulates AS in cancer cells. However, the effective concentration of amiloride required to modulate AS is too high for use in cancer treatment. In this study, we used computational algorithms to screen potential amiloride derivatives for their ability to regulate AS in cancer cells. We found that 3,5-diamino-6-chloro-N-(N-(2,6-dichlorobenzoyl)carbamimidoyl)pyrazine-2-carboxamide (BS008) can regulate AS of apoptotic gene transcripts, including HIPK3, SMAC, and BCL-X, at a lower concentration than amiloride. This splicing regulation involved various splicing factors, and it was accompanied by a change in the phosphorylation state of serine/arginine-rich proteins (SR proteins). RNA sequencing was performed to reveal that AS of many other apoptotic gene transcripts, such as AATF, ATM, AIFM1, NFKB1, and API5, was also modulated by BS008. In vivo experiments further indicated that treatment of tumor-bearing mice with BS008 resulted in a marked decrease in tumor size. BS008 also had inhibitory effects in vitro, either alone or in a synergistic combination with the cytotoxic chemotherapeutic agents sorafenib and nilotinib. BS008 enabled sorafenib dose reduction without compromising antitumor activity. These findings suggest that BS008 may possess therapeutic potential for cancer treatment.
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Affiliation(s)
- Chien-Chin Lee
- Epigenome Research Center, China Medical University Hospital, Taichung, Taiwan
| | - Wen-Hsin Chang
- Epigenome Research Center, China Medical University Hospital, Taichung, Taiwan.,Department of Primary Care Medicine, Taipei Medical University Hospital, Taiwan
| | - Ya-Sian Chang
- Epigenome Research Center, China Medical University Hospital, Taichung, Taiwan.,Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan.,Center for Precision Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Jinn-Moon Yang
- TIGP-Bioinformatics, Institute of Information Science, Academia Sinica, Taipei, Taiwan.,Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.,Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan
| | - Chih-Shiang Chang
- Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan
| | - Kai-Cheng Hsu
- Graduate Institute of Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taiwan
| | - Yun-Ti Chen
- Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan
| | - Ting-Yuan Liu
- Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Yu-Chia Chen
- Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Shyr-Yi Lin
- Department of Primary Care Medicine, Taipei Medical University Hospital, Taiwan.,Department of General Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taiwan.,TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taiwan
| | - Yang-Chang Wu
- Graduate Institute of Natural Products, Kaohsiung Medical University, Taiwan.,Research Center for Natural Products and Drug Development, Kaohsiung Medical University, Taiwan.,Department of Medical Research, Kaohsiung Medical University Hospital, Taiwan.,Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung, Taiwan
| | - Jan-Gowth Chang
- Epigenome Research Center, China Medical University Hospital, Taichung, Taiwan.,Department of Primary Care Medicine, Taipei Medical University Hospital, Taiwan.,Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan
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10
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Healy TM, Schulte PM. Patterns of alternative splicing in response to cold acclimation in fish. ACTA ACUST UNITED AC 2019; 222:jeb.193516. [PMID: 30692167 DOI: 10.1242/jeb.193516] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 01/23/2019] [Indexed: 12/26/2022]
Abstract
Phenotypic plasticity is an important aspect of an organism's response to environmental change that often requires the modulation of gene expression. These changes in gene expression can be quantitative, as a result of increases or decreases in the amounts of specific transcripts, or qualitative, as a result of the expression of alternative transcripts from the same gene (e.g. via alternative splicing of pre-mRNAs). Although the role of quantitative changes in gene expression in phenotypic plasticity is well known, relatively few studies have examined the role of qualitative changes. Here, we use skeletal muscle RNA-seq data from Atlantic killifish (Fundulus heteroclitus), threespine stickleback (Gasterosteus aculeatus) and zebrafish (Danio rerio) to investigate the extent of qualitative changes in gene expression in response to cold acclimation. Fewer genes demonstrated alternative splicing than differential expression as a result of cold acclimation; however, differences in splicing were detected for 426 to 866 genes depending on species, indicating that large numbers of qualitative changes in gene expression are associated with cold acclimation. Many of these alternatively spliced genes were also differentially expressed, and there was functional enrichment for involvement in muscle contraction among the genes demonstrating qualitative changes in response to cold acclimation. Additionally, there was a common group of 29 genes with cold-acclimation-mediated changes in splicing in all three species, suggesting that there may be a set of genes with expression patterns that respond qualitatively to prolonged exposure to cold temperatures across fishes.
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Affiliation(s)
- Timothy M Healy
- The University of British Columbia, Department of Zoology, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4
| | - Patricia M Schulte
- The University of British Columbia, Department of Zoology, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4
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Nakaminami K, Seki M. RNA Regulation in Plant Cold Stress Response. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1081:23-44. [PMID: 30288702 DOI: 10.1007/978-981-13-1244-1_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In addition to plants, all organisms react to environmental stimuli via the perception of signals and subsequently respond through alterations of gene expression. However, genes/mRNAs are usually not the functional unit themselves, and instead, resultant protein products with individual functions result in various acquired phenotypes. In order to fully characterize the adaptive responses of plants to environmental stimuli, it is essential to determine the level of proteins, in addition to the regulation of mRNA expression. This regulatory step, which is referred to as "mRNA posttranscriptional regulation," occurs subsequent to mRNA transcription and prior to translation. Although these RNA regulatory mechanisms have been well-studied in many organisms, including plants, it is not fully understood how plants respond to environmental stimuli, such as cold stress, via these RNA regulations.A recent study described several RNA regulatory factors in relation to environmental stress responses, including plant cold stress tolerance. In this chapter, the functions of RNA regulatory factors and comprehensive analyses related to the RNA regulations involved in cold stress response are summarized, such as mRNA maturation, including capping, splicing, polyadenylation of mRNA, and the quality control system of mRNA; mRNA degradation, including the decapping step; and mRNA stabilization. In addition, the putative roles of messenger ribonucleoprotein (mRNP) granules, such as processing bodies (PBs) and stress granules (SGs), which are cytoplasmic particles, are described in relation to RNA regulations under stress conditions. These RNA regulatory systems are important for adjusting or fine-tuning and determining the final levels of mRNAs and proteins in order to adapt or respond to environmental stresses. Collectively, these new areas of study revealed that plants possess precise novel regulatory mechanisms which specifically function in the response to cold stress.
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Affiliation(s)
- Kentaro Nakaminami
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan.
| | - Motoaki Seki
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan
- Plant Epigenome Regulation Laboratory, Cluster for Pioneering Research, RIKEN, Wako, Saitama, Japan
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology (JST), Kawaguchi, Saitama, Japan
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12
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Liu Z, Qin J, Tian X, Xu S, Wang Y, Li H, Wang X, Peng H, Yao Y, Hu Z, Ni Z, Xin M, Sun Q. Global profiling of alternative splicing landscape responsive to drought, heat and their combination in wheat (Triticum aestivum L.). PLANT BIOTECHNOLOGY JOURNAL 2018; 16:714-726. [PMID: 28834352 PMCID: PMC5814593 DOI: 10.1111/pbi.12822] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/17/2017] [Accepted: 08/10/2017] [Indexed: 05/13/2023]
Abstract
Plant can acquire tolerance to environmental stresses via transcriptome reprogramming at transcriptional and alternative splicing (AS) levels. However, how AS coordinates with transcriptional regulation to contribute to abiotic stresses responses is still ambiguous. In this study, we performed genome-wide analyses of AS responses to drought stress (DS), heat stress (HS) and their combination (HD) in wheat seedlings, and further compared them with transcriptional responses. In total, we found 200, 3576 and 4056 genes exhibiting significant AS pattern changes in response to DS, HS and HD, respectively, and combined drought and heat stress can induce specific AS compared with individual one. In addition, wheat homeologous genes exhibited differential AS responses under stress conditions that more AS events occurred on B subgenome than on A and D genomes. Comparison of genes regulated at AS and transcriptional levels showed that only 12% of DS-induced AS genes were subjected to transcriptional regulation, whereas the proportion increased to ~40% under HS and HD. Functional enrichment analysis revealed that abiotic stress-responsive pathways tended to be highly overrepresented among these overlapped genes under HS and HD. Thus, we proposed that transcriptional regulation may play a major role in response to DS, which coordinates with AS regulation to contribute to HS and HD tolerance in wheat.
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Affiliation(s)
- Zhenshan Liu
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of AgronomyNorthwest A&F UniversityYanglingShaanxiChina
| | - Jinxia Qin
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of AgronomyNorthwest A&F UniversityYanglingShaanxiChina
| | - Xuejun Tian
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Shengbao Xu
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of AgronomyNorthwest A&F UniversityYanglingShaanxiChina
| | - Yu Wang
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of AgronomyNorthwest A&F UniversityYanglingShaanxiChina
| | - Hongxia Li
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of AgronomyNorthwest A&F UniversityYanglingShaanxiChina
| | - Xiaoming Wang
- State Key Laboratory of Crop Stress Biology for Arid AreasCollege of AgronomyNorthwest A&F UniversityYanglingShaanxiChina
| | - Huiru Peng
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Yingyin Yao
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Zhaorong Hu
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Zhongfu Ni
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Mingming Xin
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Qixin Sun
- State Key Laboratory for AgrobiotechnologyKey Laboratory of Crop Heterosis Utilization (MOE)Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
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13
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Kiegle EA, Garden A, Lacchini E, Kater MM. A Genomic View of Alternative Splicing of Long Non-coding RNAs during Rice Seed Development Reveals Extensive Splicing and lncRNA Gene Families. FRONTIERS IN PLANT SCIENCE 2018; 9:115. [PMID: 29467783 PMCID: PMC5808331 DOI: 10.3389/fpls.2018.00115] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 01/22/2018] [Indexed: 05/08/2023]
Abstract
Alternative splicing (AS) is a key modulator of development in many eukaryotic organisms. In plants, alternative splice forms of non-coding RNAs (ncRNAs) are known to modulate flowering time in Arabidopsis and fertility in rice. Here we demonstrate that alternative splicing of coding and long non-coding RNAs occurs during rice seed development by comparing AS in immature seeds vs. embryo and endosperm of mature seeds. Based on computational predictions of AS events determined from a Bayesian analysis of junction counts of RNA-seq datasets, differential splicing of protein-coding, and non-coding RNAs was determined. In contrast to roots, leaves, flowers, buds, and reproductive meristems, developing seeds had 5.8-57 times more predicted AS. Primers designed to span introns and exons were used to detect AS events predicted by rMATs in cDNA derived from early (milk) seed, embryo, and endosperm. Comparing milk seed vs. mature embryo and endosperm, AS of MORC7 (a gene implicated in epigenetic gene silencing), was markedly different. Long non-coding RNAs (lncRNAs) also underwent AS during the transition from milk seed to mature embryo and endosperm, with a complex gene structure, and were more extensively processed than predicted by current genome annotation. Exon retention of lncRNAs was enhanced in embryos. Searching all 5,515 lncRNAs in the NCBI genome annotation uncovered gene families based on highly conserved regions shared by groups of 3-35 lncRNAs. The homologies to other lncRNAs, as well as homologies to coding sequences, and the genomic context of lncRNAs provide inroads for functional analysis of multi-exonic lncRNAs that can be extensively processed during seed development.
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Abstract
This article comments on: Capovilla G, Symeonidi E, Wu R, Schmid M. 2017. Contribution of major FLM isoforms to temperature-dependent mediated flowering in Arabidopsis thaliana. Journal of Experimental Botany 68, 5117–5127.
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Affiliation(s)
- Rainer Melzer
- School of Biology and Environmental Science, University College Dublin, Dublin, Ireland
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15
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Healy TM, Bryant HJ, Schulte PM. Mitochondrial genotype and phenotypic plasticity of gene expression in response to cold acclimation in killifish. Mol Ecol 2017; 26:814-830. [DOI: 10.1111/mec.13945] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 11/11/2016] [Accepted: 11/16/2016] [Indexed: 01/07/2023]
Affiliation(s)
- Timothy M. Healy
- Department of Zoology; The University of British Columbia; 6270 University Blvd Vancouver BC Canada V6T 1Z4
| | - Heather J. Bryant
- Department of Zoology; The University of British Columbia; 6270 University Blvd Vancouver BC Canada V6T 1Z4
| | - Patricia M. Schulte
- Department of Zoology; The University of British Columbia; 6270 University Blvd Vancouver BC Canada V6T 1Z4
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16
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Kim DW, Jeon SJ, Hwang SM, Hong JC, Bahk JD. The C3H-type zinc finger protein GDS1/C3H42 is a nuclear-speckle-localized protein that is essential for normal growth and development in Arabidopsis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 250:141-153. [PMID: 27457991 DOI: 10.1016/j.plantsci.2016.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 06/10/2016] [Accepted: 06/12/2016] [Indexed: 05/27/2023]
Abstract
Eukaryotic C3H-type zinc finger proteins (Znfs) comprise a large family of regulatory proteins involved in many aspects of plant stress response, growth and development. However, compared to mammalian, only a few plant Znfs have been functionally characterized. Here, T-DNA inserted gds1 (growth, development and splicing 1) mutant, displayed abnormal growth throughout the lifecycle owing to the reduction of cell size and number. Inverse PCR analysis revealed that the abnormal growth was caused by the disruption of At3g47120, which encodes a C3H42 protein belonging to the C-X7-C-X5-C-X3-H class of the Znf family. GDS1 was ubiquitously transcribed, but shows high levels of expression in young seedling and unexpanded new leaves. In gds1, the transcripts of many growth- and development-related genes were down-regulated, and the auxin response was dramatically reduced. A fluorescence-based assay revealed that the GDS1 protein was localized to the nucleus, prominently in the speckle compartments. Its arginine/serine dipeptide-rich-like (RS-like) domain was essential for nuclear localization. In addition, the SR1, SRm102 and U1-70K components of the U1 spliceosome interacted with GDS1 in the nuclear speckle compartments. Taken together, these suggest that GDS1, a nuclear-speckle-associated Znf, might play a significant role in splicing during plant growth and development.
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Affiliation(s)
- Dae Won Kim
- Division of Applied Life Science (BK21Plus), PMBBRC, Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Su Jeong Jeon
- Division of Applied Life Science (BK21Plus), PMBBRC, Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Sung Min Hwang
- Division of Applied Life Science (BK21Plus), PMBBRC, Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Jong Chan Hong
- Division of Applied Life Science (BK21Plus), PMBBRC, Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Jeong Dong Bahk
- Division of Applied Life Science (BK21Plus), PMBBRC, Graduate School of Gyeongsang National University, Jinju 660-701, Republic of Korea.
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17
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Abdel-Ghany SE, Hamilton M, Jacobi JL, Ngam P, Devitt N, Schilkey F, Ben-Hur A, Reddy ASN. A survey of the sorghum transcriptome using single-molecule long reads. Nat Commun 2016; 7:11706. [PMID: 27339290 PMCID: PMC4931028 DOI: 10.1038/ncomms11706] [Citation(s) in RCA: 320] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 04/20/2016] [Indexed: 12/31/2022] Open
Abstract
Alternative splicing and alternative polyadenylation (APA) of pre-mRNAs greatly contribute to transcriptome diversity, coding capacity of a genome and gene regulatory mechanisms in eukaryotes. Second-generation sequencing technologies have been extensively used to analyse transcriptomes. However, a major limitation of short-read data is that it is difficult to accurately predict full-length splice isoforms. Here we sequenced the sorghum transcriptome using Pacific Biosciences single-molecule real-time long-read isoform sequencing and developed a pipeline called TAPIS (Transcriptome Analysis Pipeline for Isoform Sequencing) to identify full-length splice isoforms and APA sites. Our analysis reveals transcriptome-wide full-length isoforms at an unprecedented scale with over 11,000 novel splice isoforms. Additionally, we uncover APA of ∼11,000 expressed genes and more than 2,100 novel genes. These results greatly enhance sorghum gene annotations and aid in studying gene regulation in this important bioenergy crop. The TAPIS pipeline will serve as a useful tool to analyse Iso-Seq data from any organism. Alternative splicing and alternative polyadenylation (APA) contribute to mRNA diversity but are difficult to assess using short read RNA-seq data. Here, the authors use single molecule long-read isoform sequencing and develop a computational pipeline to identify full-length splice isoforms and APA sites in sorghum.
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Affiliation(s)
- Salah E Abdel-Ghany
- Department of Biology, Program in Molecular Plant Biology, Program in Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Michael Hamilton
- Department of Computer Science, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Jennifer L Jacobi
- National Center for Genome Resources, 2935 Rodeo Park Dr East, Santa Fe, New Mexico 87505, USA
| | - Peter Ngam
- National Center for Genome Resources, 2935 Rodeo Park Dr East, Santa Fe, New Mexico 87505, USA
| | - Nicholas Devitt
- National Center for Genome Resources, 2935 Rodeo Park Dr East, Santa Fe, New Mexico 87505, USA
| | - Faye Schilkey
- National Center for Genome Resources, 2935 Rodeo Park Dr East, Santa Fe, New Mexico 87505, USA
| | - Asa Ben-Hur
- Department of Computer Science, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Anireddy S N Reddy
- Department of Biology, Program in Molecular Plant Biology, Program in Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523, USA
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18
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Capovilla G, Pajoro A, Immink RGH, Schmid M. Role of alternative pre-mRNA splicing in temperature signaling. CURRENT OPINION IN PLANT BIOLOGY 2015; 27:97-103. [PMID: 26190743 DOI: 10.1016/j.pbi.2015.06.016] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/18/2015] [Accepted: 06/20/2015] [Indexed: 05/20/2023]
Abstract
Developmental plasticity enables plants to respond rapidly to changing environmental conditions, such as temperature fluctuations. Understanding how plants measure temperature and integrate this information into developmental programs at the molecular level will be essential to breed thermo-tolerant crop varieties. Recent studies identified alternative splicing (AS) as a possible 'molecular thermometer', allowing plants to quickly adjust the abundance of functional transcripts to environmental perturbations. In this review, recent advances regarding the effects of temperature-responsive AS on plant development will be discussed, with emphasis on the circadian clock and flowering time control. The challenge for the near future will be to understand the molecular mechanisms by which temperature can influence AS regulation.
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Affiliation(s)
- Giovanna Capovilla
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, 72074 Tübingen, Germany
| | - Alice Pajoro
- Plant Research International, Bioscience, 6708 PB Wageningen, The Netherlands; Laboratory of Molecular Biology, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Richard G H Immink
- Plant Research International, Bioscience, 6708 PB Wageningen, The Netherlands; Laboratory of Molecular Biology, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Markus Schmid
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, 72074 Tübingen, Germany; Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, S-901 87 Umea, Sweden.
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19
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Abstract
Alternative pre-messenger RNA splicing in higher plants emerges as an important layer of regulation upon exposure to exogenous and endogenous cues. Accordingly, mutants defective in RNA-binding proteins predicted to function in the splicing process show severe phenotypic alterations. Among those are developmental defects, impaired responses to pathogen threat or abiotic stress factors, and misregulation of the circadian timing system. A suite of splicing factors has been identified in the model plant Arabidopsis thaliana. Here we summarize recent insights on how defects in these splicing factors impair plant performance.
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20
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MAF2 Is Regulated by Temperature-Dependent Splicing and Represses Flowering at Low Temperatures in Parallel with FLM. PLoS One 2015; 10:e0126516. [PMID: 25955034 PMCID: PMC4425511 DOI: 10.1371/journal.pone.0126516] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/03/2015] [Indexed: 11/19/2022] Open
Abstract
Plants enter their reproductive phase when the environmental conditions are favourable for the successful production of progeny. The transition from vegetative to reproductive phase is influenced by several environmental factors including ambient temperature. In the model plant Arabidopsis thaliana, SHORT VEGETATIVE PHASE (SVP) is critical for this pathway; svp mutants cannot modify their flowering time in response to ambient temperature. SVP encodes a MADS-box transcription factor that directly represses genes that promote flowering. SVP binds DNA in complexes with other MADS-box transcription factors, including FLOWERING LOCUS M (FLM), which acts with SVP to repress the floral transition at low temperatures. Small temperature changes post-transcriptionally regulate FLM through temperature-dependent alternative splicing (TD-AS). As ambient temperature increases, the predominant FLM splice isoform shifts to encode a protein incapable of exerting a repressive effect on flowering. Here we characterize a closely related MADS-box transcription factor, MADS AFFECTING FLOWERING2 (MAF2), which has independently evolved TD-AS. At low temperatures the most abundant MAF2 splice variant encodes a protein that interacts with SVP to repress flowering. At increased temperature the relative abundance of splice isoforms shifts in favour of an intron-retaining variant that introduces a premature termination codon. We show that this isoform encodes a protein that cannot interact with SVP or repress flowering. At lower temperatures MAF2 and SVP repress flowering in parallel with FLM and SVP, providing an additional input to sense ambient temperature for the control of flowering.
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21
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Palusa SG, Reddy ASN. Differential recruitment of splice variants from SR pre-mRNAs to polysomes during development and in response to stresses. PLANT & CELL PHYSIOLOGY 2015; 56:421-7. [PMID: 25637375 DOI: 10.1093/pcp/pcv010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We have previously shown that precursor mRNAs (pre-mRNAs) of serine/arginine-rich (SR) proteins are extensively alternatively spliced to generate approximately 100 distinct splice variants from 14 SR genes and that the splicing pattern of SR pre-mRNAs changes in different organs and in response to abiotic stresses. About half of the splice variants are potential targets of nonsense-mediated decay (NMD) and 25 splice forms were confirmed to be real NMD targets. However, it is not known whether (i) all splice variants are recruited to polysomes for translation; (ii) there is a preferential recruitment of specific splice isoforms to polysomes; and (iii) there is a differential recruitment of splice variants during development and in response to stresses. To address these questions, we analyzed the association of SR splice variants with polysomes from seedlings, different organs and seedlings exposed to heat and cold stress. In seedlings, about one-third of the splice variants (22 out of 72) are not recruited to polysomes. Among those associated with polysomes, the functional isoforms that code for full-length proteins and some candidate putative and confirmed NMD targets were identified. There was preferential recruitment of some splice forms over others. Predominant recruitment of functional isoforms along with a few NMD candidates was found in different organs. Furthermore, we observed differential recruitment of isoforms in different organs. Heat and cold stress enhanced or reduced recruitment of specific splice variants. Our studies reveal differential recruitment of SR splice variants to polysomes under normal conditions, during development and in response to stresses.
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Affiliation(s)
- Saiprasad Goud Palusa
- Department of Biology, Program in Molecular Plant Biology, Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Anireddy S N Reddy
- Department of Biology, Program in Molecular Plant Biology, Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
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22
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Comprehensive analysis of alternative splicing in Digitalis purpurea by strand-specific RNA-Seq. PLoS One 2014; 9:e106001. [PMID: 25167195 PMCID: PMC4148352 DOI: 10.1371/journal.pone.0106001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/25/2014] [Indexed: 12/23/2022] Open
Abstract
Digitalis purpurea (D. purpurea) is one of the most important medicinal plants and is well known in the treatment of heart failure because of the cardiac glycosides that are its main active compounds. However, in the absence of strand specific sequencing information, the post-transcriptional mechanism of gene regulation in D. purpurea thus far remains unknown. In this study, a strand-specific RNA-Seq library was constructed and sequenced using Illumina HiSeq platforms to characterize the transcriptome of D. purpurea with a focus on alternative splicing (AS) events and the effect of AS on protein domains. De novo RNA-Seq assembly resulted in 48,475 genes. Based on the assembled transcripts, we reported a list of 3,265 AS genes, including 5,408 AS events in D. purpurea. Interestingly, both glycosyltransferases and monooxygenase, which were involved in the biosynthesis of cardiac glycosides, are regulated by AS. A total of 2,422 AS events occurred in coding regions, and 959 AS events were located in the regions of 882 unique protein domains, which could affect protein function. This D. purpurea transcriptome study substantially increased the expressed sequence resource and presented a better understanding of post-transcriptional regulation to further facilitate the medicinal applications of D. purpurea for human health.
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23
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Cui Z, Xu Q, Wang X. Regulation of the circadian clock through pre-mRNA splicing in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:1973-80. [PMID: 24604736 DOI: 10.1093/jxb/eru085] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Alternative splicing plays an important role in regulating gene functions and enhancing the diversity of the proteome in plants. Most of the genes are interrupted by introns in Arabidopsis. More than half of the intron-split genes involved in multiple biological processes including the circadian clock are alternatively spliced. In this review, we focus on the involvement of alternative splicing in the regulation of the circadian clock.
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Affiliation(s)
- Zhibo Cui
- Rice Research Institute; Key Laboratory of Northeast Rice Biology and Breeding, Ministry of Agriculture; Key Laboratory of Northern Japonica Super Rice Breeding, Ministry of Education; Shenyang Agricultural University, Shenyang 110866, China
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24
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Rauch HB, Patrick TL, Klusman KM, Battistuzzi FU, Mei W, Brendel VP, Lal SK. Discovery and expression analysis of alternative splicing events conserved among plant SR proteins. Mol Biol Evol 2013; 31:605-13. [PMID: 24356560 DOI: 10.1093/molbev/mst238] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The high frequency of alternative splicing among the serine/arginine-rich (SR) family of proteins in plants has been linked to important roles in gene regulation during development and in response to environmental stress. In this article, we have searched and manually annotated all the SR proteins in the genomes of maize and sorghum. The experimental validation of gene structure by reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed, with few exceptions, that SR genes produced multiple isoforms of transcripts by alternative splicing. Despite sharing high structural similarity and conserved positions of the introns, the profile of alternative splicing diverged significantly between maize and sorghum for the vast majority of SR genes. These include many transcript isoforms discovered by RT-PCR and not represented in extant expressed sequence tag (EST) collection. However, we report the occurrence of various maize and sorghum SR mRNA isoforms that display evolutionary conservation of splicing events with their homologous SR genes in Arabidopsis and moss. Our data also indicate an important role of both 5' and 3' untranslated regions in the regulation of SR gene expression. These observations have potentially important implications for the processes of evolution and adaptation of plants to land.
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25
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Reddy AS, Marquez Y, Kalyna M, Barta A. Complexity of the alternative splicing landscape in plants. THE PLANT CELL 2013; 25:3657-83. [PMID: 24179125 PMCID: PMC3877793 DOI: 10.1105/tpc.113.117523] [Citation(s) in RCA: 515] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Revised: 09/27/2013] [Accepted: 10/08/2013] [Indexed: 05/18/2023]
Abstract
Alternative splicing (AS) of precursor mRNAs (pre-mRNAs) from multiexon genes allows organisms to increase their coding potential and regulate gene expression through multiple mechanisms. Recent transcriptome-wide analysis of AS using RNA sequencing has revealed that AS is highly pervasive in plants. Pre-mRNAs from over 60% of intron-containing genes undergo AS to produce a vast repertoire of mRNA isoforms. The functions of most splice variants are unknown. However, emerging evidence indicates that splice variants increase the functional diversity of proteins. Furthermore, AS is coupled to transcript stability and translation through nonsense-mediated decay and microRNA-mediated gene regulation. Widespread changes in AS in response to developmental cues and stresses suggest a role for regulated splicing in plant development and stress responses. Here, we review recent progress in uncovering the extent and complexity of the AS landscape in plants, its regulation, and the roles of AS in gene regulation. The prevalence of AS in plants has raised many new questions that require additional studies. New tools based on recent technological advances are allowing genome-wide analysis of RNA elements in transcripts and of chromatin modifications that regulate AS. Application of these tools in plants will provide significant new insights into AS regulation and crosstalk between AS and other layers of gene regulation.
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Affiliation(s)
- Anireddy S.N. Reddy
- Department of Biology, Program in Molecular Plant Biology, Program in Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado 80523
- Address correspondence to
| | - Yamile Marquez
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna A-1030, Austria
| | - Maria Kalyna
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna A-1030, Austria
| | - Andrea Barta
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna A-1030, Austria
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26
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Valledor L, Furuhashi T, Hanak AM, Weckwerth W. Systemic cold stress adaptation of Chlamydomonas reinhardtii. Mol Cell Proteomics 2013; 12:2032-47. [PMID: 23564937 PMCID: PMC3734567 DOI: 10.1074/mcp.m112.026765] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 03/15/2013] [Indexed: 11/06/2022] Open
Abstract
Chlamydomonas reinhardtii is one of the most important model organisms nowadays phylogenetically situated between higher plants and animals (Merchant et al. 2007). Stress adaptation of this unicellular model algae is in the focus because of its relevance to biomass and biofuel production. Here, we have studied cold stress adaptation of C. reinhardtii hitherto not described for this algae whereas intensively studied in higher plants. Toward this goal, high throughput mass spectrometry was employed to integrate proteome, metabolome, physiological and cell-morphological changes during a time-course from 0 to 120 h. These data were complemented with RT-qPCR for target genes involved in central metabolism, signaling, and lipid biosynthesis. Using this approach dynamics in central metabolism were linked to cold-stress dependent sugar and autophagy pathways as well as novel genes in C. reinhardtii such as CKIN1, CKIN2 and a hitherto functionally not annotated protein named CKIN3. Cold stress affected extensively the physiology and the organization of the cell. Gluconeogenesis and starch biosynthesis pathways are activated leading to a pronounced starch and sugar accumulation. Quantitative lipid profiles indicate a sharp decrease in the lipophilic fraction and an increase in polyunsaturated fatty acids suggesting this as a mechanism of maintaining membrane fluidity. The proteome is completely remodeled during cold stress: specific candidates of the ribosome and the spliceosome indicate altered biosynthesis and degradation of proteins important for adaptation to low temperatures. Specific proteasome degradation may be mediated by the observed cold-specific changes in the ubiquitinylation system. Sparse partial least squares regression analysis was applied for protein correlation network analysis using proteins as predictors and Fv/Fm, FW, total lipids, and starch as responses. We applied also Granger causality analysis and revealed correlations between proteins and metabolites otherwise not detectable. Twenty percent of the proteins responsive to cold are uncharacterized proteins. This presents a considerable resource for new discoveries in cold stress biology in alga and plants.
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Affiliation(s)
- Luis Valledor
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
| | - Takeshi Furuhashi
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
| | - Anne-Mette Hanak
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
| | - Wolfram Weckwerth
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
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27
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Streitner C, Simpson CG, Shaw P, Danisman S, Brown JW, Staiger D. Small changes in ambient temperature affect alternative splicing in Arabidopsis thaliana. PLANT SIGNALING & BEHAVIOR 2013; 8:e24638. [PMID: 23656882 PMCID: PMC3907436 DOI: 10.4161/psb.24638] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/10/2013] [Accepted: 04/10/2013] [Indexed: 05/20/2023]
Abstract
Alternative splicing (AS) gives rise to multiple mRNA isoforms from the same gene, providing possibilities to regulate gene expression beyond the level of transcription. In a recent paper in Nucleic Acids Research we used a high resolution RT-PCR based panel to study changes in AS patterns in plants with altered levels of an hnRNP-like RNA-binding protein in Arabidopsis thaliana. Furthermore, we detected significant changes in AS patterns between different Arabidopsis ecotypes. Here we investigated how small changes in ambient temperature affect AS. We found significant changes in AS for 12 of 28 investigated events (43%) upon transfer of Arabidopsis plants from 20°C to 16°C and for 6 of the 28 investigated events (21%) upon transfer from 20°C to 24°C.
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Affiliation(s)
| | - Craig G. Simpson
- Cell and Molecular Sciences; The James Hutton Institute; Invergowrie, Scotland, UK
| | - Paul Shaw
- Information and Computational Sciences; The James Hutton Institute; Invergowrie, Scotland UK
| | | | - John W.S. Brown
- Cell and Molecular Sciences; The James Hutton Institute; Invergowrie, Scotland, UK
- Division of Plant Sciences; University of Dundee at The James Hutton Institute; Invergowrie, Scotland UK
| | - Dorothee Staiger
- Molecular Cell Physiology; Bielefeld University; Bielefeld, Germany
- Institute for Genome Research and Systems Biology; CeBiTec; Bielefeld, Germany
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28
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Seo PJ, Park MJ, Park CM. Alternative splicing of transcription factors in plant responses to low temperature stress: mechanisms and functions. PLANTA 2013; 237:1415-24. [PMID: 23624977 PMCID: PMC3664756 DOI: 10.1007/s00425-013-1882-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 04/08/2013] [Indexed: 05/19/2023]
Abstract
Transcription factors play a central role in the gene regulatory networks that mediate various aspects of plant developmental processes and responses to environmental changes. Therefore, their activities are elaborately regulated at multiple steps. In particular, accumulating evidence illustrates that post-transcriptional control of mRNA metabolism is a key molecular scheme that modulates the transcription factor activities in plant responses to temperature fluctuations. Transcription factors have a modular structure consisting of distinct protein domains essential for DNA binding, dimerization, and transcriptional regulation. Alternative splicing produces multiple proteins having different structural domain compositions from a single transcription factor gene. Recent studies have shown that alternative splicing of some transcription factor genes generates small interfering peptides (siPEPs) that negatively regulate the target transcription factors via peptide interference (PEPi), constituting self-regulatory circuits in plant cold stress response. A number of splicing factors, which are involved in RNA binding, splice site selection, and spliceosome assembly, are also affected by temperature fluctuations, supporting the close association of alternative splicing of transcription factors with plant responses to low temperatures. In this review, we summarize recent progress on the temperature-responsive alternative splicing of transcription factors in plants with emphasis on the siPEP-mediated PEPi mechanism.
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Affiliation(s)
- Pil Joon Seo
- Department of Chemistry, Chonbuk National University, Jeonju, 561-756 Korea
| | - Mi-Jeong Park
- Department of Chemistry, Seoul National University, Seoul, 151-742 Korea
| | - Chung-Mo Park
- Department of Chemistry, Seoul National University, Seoul, 151-742 Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, 151-742 Korea
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29
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Syed NH, Kalyna M, Marquez Y, Barta A, Brown JW. Alternative splicing in plants--coming of age. TRENDS IN PLANT SCIENCE 2012; 17:616-23. [PMID: 22743067 PMCID: PMC3466422 DOI: 10.1016/j.tplants.2012.06.001] [Citation(s) in RCA: 335] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 05/30/2012] [Accepted: 06/02/2012] [Indexed: 05/18/2023]
Abstract
More than 60% of intron-containing genes undergo alternative splicing (AS) in plants. This number will increase when AS in different tissues, developmental stages, and environmental conditions are explored. Although the functional impact of AS on protein complexity is still understudied in plants, recent examples demonstrate its importance in regulating plant processes. AS also regulates transcript levels and the link with nonsense-mediated decay and generation of unproductive mRNAs illustrate the need for both transcriptional and AS data in gene expression analyses. AS has influenced the evolution of the complex networks of regulation of gene expression and variation in AS contributed to adaptation of plants to their environment and therefore will impact strategies for improving plant and crop phenotypes.
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Affiliation(s)
- Naeem H. Syed
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, UK
| | - Maria Kalyna
- Max F. Perutz Laboratories, Medical University of Vienna, Dr Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Yamile Marquez
- Max F. Perutz Laboratories, Medical University of Vienna, Dr Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Andrea Barta
- Max F. Perutz Laboratories, Medical University of Vienna, Dr Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - John W.S. Brown
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, UK
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, UK
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Yoshimura K, Mori T, Yokoyama K, Koike Y, Tanabe N, Sato N, Takahashi H, Maruta T, Shigeoka S. Identification of alternative splicing events regulated by an Arabidopsis serine/arginine-like protein, atSR45a, in response to high-light stress using a tiling array. PLANT & CELL PHYSIOLOGY 2011; 52:1786-805. [PMID: 21862516 DOI: 10.1093/pcp/pcr115] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We have demonstrated that an Arabidopsis serine/arginine rich-like protein, atSR45a, interacts with other splicing factors and its expression is markedly induced by high-light stress, suggesting the involvement of atSR45a in the regulation of stress-responsive alternative splicing. A whole-genome tiling array identified the alternative splicing of genes regulated by atSR45a by comparing gene expression profiles in wild-type and knockout atSR45a (KO-sr45a) plants under high-light stress. The expression levels of genomic regions within 217 genes were significantly altered in the KO-sr45a plants compared with the wild-type plants. Many genes encoded factors involved in signal transduction, cell cycle and DNA processing, protein fate and transcription. A semi-quantitative reverse transcription-PCR (RT-PCR) analysis confirmed changes in the transcript levels and/or alternative splicing efficiency under high-light stress in 18 genes, suggesting that atSR45a affects directly or indirectly not only alternative splicing efficiency but also the transcription of these target genes. Changes in the expression of atSR45a in response to high-light stress temporally correlated with changes in the alternative splicing efficiency and transcript levels of three and one target genes, respectively. Sequencing of the alternatively spliced variants of three target genes showed that atSR45a suppresses the splicing efficiency of intron retention-type alternative splicing events. These findings indicated the importance of atSR45a to the diversification of the transcriptome under high-light stress.
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Affiliation(s)
- Kazuya Yoshimura
- Department of Food and Nutritional Science, College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan
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Reddy ASN, Shad Ali G. Plant serine/arginine-rich proteins: roles in precursor messenger RNA splicing, plant development, and stress responses. WILEY INTERDISCIPLINARY REVIEWS-RNA 2011; 2:875-89. [PMID: 21766458 DOI: 10.1002/wrna.98] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Global analyses of splicing of precursor messenger RNAs (pre-mRNAs) have revealed that alternative splicing (AS) is highly pervasive in plants. Despite the widespread occurrence of AS in plants, the mechanisms that control splicing and the roles of splice variants generated from a gene are poorly understood. Studies on plant serine/arginine-rich (SR) proteins, a family of highly conserved proteins, suggest their role in both constitutive splicing and AS of pre-mRNAs. SR proteins have a characteristic domain structure consisting of one or two RNA recognition motifs at the N-terminus and a C-terminal RS domain rich in arginine/serine dipeptides. Plants have many more SR proteins compared to animals including several plant-specific subfamilies. Pre-mRNAs of plant SR proteins are extensively alternatively spliced to increase the transcript complexity by about six-fold. Some of this AS is controlled in a tissue- and development-specific manner. Furthermore, AS of SR pre-mRNAs is altered by various stresses, raising the possibility of rapid reprogramming of the whole transcriptome by external signals through regulation of the splicing of these master regulators of splicing. Most SR splice variants contain a premature termination codon and are degraded by up-frameshift 3 (UPF3)-mediated nonsense-mediated decay (NMD), suggesting a link between NMD and regulation of expression of the functional transcripts of SR proteins. Limited functional studies with plant SRs suggest key roles in growth and development and plant responses to the environment. Here, we discuss the current status of research on plant SRs and some promising approaches to address many unanswered questions about plant SRs.
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Affiliation(s)
- Anireddy S N Reddy
- Department of Biology, Program in Molecular Plant Biology, Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, USA.
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Support vector machines-based identification of alternative splicing in Arabidopsis thaliana from whole-genome tiling arrays. BMC Bioinformatics 2011; 12:55. [PMID: 21324185 PMCID: PMC3051901 DOI: 10.1186/1471-2105-12-55] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Accepted: 02/16/2011] [Indexed: 11/15/2022] Open
Abstract
Background Alternative splicing (AS) is a process which generates several distinct mRNA isoforms from the same gene by splicing different portions out of the precursor transcript. Due to the (patho-)physiological importance of AS, a complete inventory of AS is of great interest. While this is in reach for human and mammalian model organisms, our knowledge of AS in plants has remained more incomplete. Experimental approaches for monitoring AS are either based on transcript sequencing or rely on hybridization to DNA microarrays. Among the microarray platforms facilitating the discovery of AS events, tiling arrays are well-suited for identifying intron retention, the most prevalent type of AS in plants. However, analyzing tiling array data is challenging, because of high noise levels and limited probe coverage. Results In this work, we present a novel method to detect intron retentions (IR) and exon skips (ES) from tiling arrays. While statistical tests have typically been proposed for this purpose, our method instead utilizes support vector machines (SVMs) which are appreciated for their accuracy and robustness to noise. Existing EST and cDNA sequences served for supervised training and evaluation. Analyzing a large collection of publicly available microarray and sequence data for the model plant A. thaliana, we demonstrated that our method is more accurate than existing approaches. The method was applied in a genome-wide screen which resulted in the discovery of 1,355 IR events. A comparison of these IR events to the TAIR annotation and a large set of short-read RNA-seq data showed that 830 of the predicted IR events are novel and that 525 events (39%) overlap with either the TAIR annotation or the IR events inferred from the RNA-seq data. Conclusions The method developed in this work expands the scarce repertoire of analysis tools for the identification of alternative mRNA splicing from whole-genome tiling arrays. Our predictions are highly enriched with known AS events and complement the A. thaliana genome annotation with respect to AS. Since all predicted AS events can be precisely attributed to experimental conditions, our work provides a basis for follow-up studies focused on the elucidation of the regulatory mechanisms underlying tissue-specific and stress-dependent AS in plants.
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Duque P. A role for SR proteins in plant stress responses. PLANT SIGNALING & BEHAVIOR 2011; 6:49-54. [PMID: 21258207 PMCID: PMC3122005 DOI: 10.4161/psb.6.1.14063] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Accepted: 10/31/2010] [Indexed: 05/19/2023]
Abstract
Members of the SR (serine/arginine-rich) protein gene family are key players in the regulation of alternative splicing, an important means of generating proteome diversity and regulating gene expression. In plants, marked changes in alternative splicing are induced by a wide variety of abiotic stresses, suggesting a role for this highly versatile gene regulation mechanism in the response to environmental cues. In support of this notion, the expression of plant SR proteins is stress-regulated at multiple levels, with environmental signals controlling their own alternative splicing patterns, phosphorylation status and subcellular distribution. Most importantly, functional links between these RNA-binding proteins and plant stress tolerance are beginning to emerge, including a role in the regulation of abscisic acid (ABA) signaling. Future identification of the physiological mRNA targets of plant SR proteins holds much promise for the elucidation of the molecular mechanisms underlying their role in the response to abiotic stress.
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Affiliation(s)
- Paula Duque
- Instituto Gulbenkian de Ciência, Oeiras, Portugal.
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Mullen MA, Olson KJ, Dallaire P, Major F, Assmann SM, Bevilacqua PC. RNA G-Quadruplexes in the model plant species Arabidopsis thaliana: prevalence and possible functional roles. Nucleic Acids Res 2010; 38:8149-63. [PMID: 20860998 PMCID: PMC3001093 DOI: 10.1093/nar/gkq804] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 08/24/2010] [Accepted: 08/30/2010] [Indexed: 01/25/2023] Open
Abstract
Tandem stretches of guanines can associate in hydrogen-bonded arrays to form G-quadruplexes, which are stabilized by K(+) ions. Using computational methods, we searched for G-Quadruplex Sequence (GQS) patterns in the model plant species Arabidopsis thaliana. We found ∼ 1200 GQS with a G(3) repeat sequence motif, most of which are located in the intergenic region. Using a Markov modeled genome, we determined that GQS are significantly underrepresented in the genome. Additionally, we found ∼ 43,000 GQS with a G(2) repeat sequence motif; notably, 80% of these were located in genic regions, suggesting that these sequences may fold at the RNA level. Gene Ontology functional analysis revealed that GQS are overrepresented in genes encoding proteins of certain functional categories, including enzyme activity. Conversely, GQS are underrepresented in other categories of genes, notably those for non-coding RNAs such as tRNAs and rRNAs. We also find that genes that are differentially regulated by drought are significantly more likely to contain a GQS. CD-detected K(+) titrations performed on representative RNAs verified formation of quadruplexes at physiological K(+) concentrations. Overall, this study indicates that GQS are present at unique locations in Arabidopsis and that folding of RNA GQS may play important roles in regulating gene expression.
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Affiliation(s)
- Melissa A. Mullen
- Department of Chemistry, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-5302, USA and Institute for Research in Immunology and Cancer (IRIC), Department of Computer Science and Operations Research, Université de Montréal, PO Box 6128, Downtown Station, Montréal, Québec H3C 3J7, Canada
| | - Kalee J. Olson
- Department of Chemistry, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-5302, USA and Institute for Research in Immunology and Cancer (IRIC), Department of Computer Science and Operations Research, Université de Montréal, PO Box 6128, Downtown Station, Montréal, Québec H3C 3J7, Canada
| | - Paul Dallaire
- Department of Chemistry, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-5302, USA and Institute for Research in Immunology and Cancer (IRIC), Department of Computer Science and Operations Research, Université de Montréal, PO Box 6128, Downtown Station, Montréal, Québec H3C 3J7, Canada
| | - François Major
- Department of Chemistry, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-5302, USA and Institute for Research in Immunology and Cancer (IRIC), Department of Computer Science and Operations Research, Université de Montréal, PO Box 6128, Downtown Station, Montréal, Québec H3C 3J7, Canada
| | - Sarah M. Assmann
- Department of Chemistry, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-5302, USA and Institute for Research in Immunology and Cancer (IRIC), Department of Computer Science and Operations Research, Université de Montréal, PO Box 6128, Downtown Station, Montréal, Québec H3C 3J7, Canada
| | - Philip C. Bevilacqua
- Department of Chemistry, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-5302, USA and Institute for Research in Immunology and Cancer (IRIC), Department of Computer Science and Operations Research, Université de Montréal, PO Box 6128, Downtown Station, Montréal, Québec H3C 3J7, Canada
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Raczynska KD, Simpson CG, Ciesiolka A, Szewc L, Lewandowska D, McNicol J, Szweykowska-Kulinska Z, Brown JWS, Jarmolowski A. Involvement of the nuclear cap-binding protein complex in alternative splicing in Arabidopsis thaliana. Nucleic Acids Res 2009; 38:265-78. [PMID: 19864257 PMCID: PMC2800227 DOI: 10.1093/nar/gkp869] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The nuclear cap-binding protein complex (CBC) participates in 5′ splice site selection of introns that are proximal to the mRNA cap. However, it is not known whether CBC has a role in alternative splicing. Using an RT–PCR alternative splicing panel, we analysed 435 alternative splicing events in Arabidopsis thaliana genes, encoding mainly transcription factors, splicing factors and stress-related proteins. Splicing profiles were determined in wild type plants, the cbp20 and cbp80(abh1) single mutants and the cbp20/80 double mutant. The alternative splicing events included alternative 5′ and 3′ splice site selection, exon skipping and intron retention. Significant changes in the ratios of alternative splicing isoforms were found in 101 genes. Of these, 41% were common to all three CBC mutants and 15% were observed only in the double mutant. The cbp80(abh1) and cbp20/80 mutants had many more changes in alternative splicing in common than did cbp20 and cbp20/80 suggesting that CBP80 plays a more significant role in alternative splicing than CBP20, probably being a platform for interactions with other splicing factors. Cap-binding proteins and the CBC are therefore directly involved in alternative splicing of some Arabidopsis genes and in most cases influenced alternative splicing of the first intron, particularly at the 5′ splice site.
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36
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Zhang XN, Mount SM. Two alternatively spliced isoforms of the Arabidopsis SR45 protein have distinct roles during normal plant development. PLANT PHYSIOLOGY 2009; 150:1450-8. [PMID: 19403727 PMCID: PMC2705014 DOI: 10.1104/pp.109.138180] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Accepted: 04/16/2009] [Indexed: 05/18/2023]
Abstract
The serine-arginine-rich (SR) proteins constitute a conserved family of pre-mRNA splicing factors. In Arabidopsis (Arabidopsis thaliana), they are encoded by 19 genes, most of which are themselves alternatively spliced. In the case of SR45, the use of alternative 3' splice sites 21 nucleotides apart generates two alternatively spliced isoforms. Isoform 1 (SR45.1) has an insertion relative to isoform 2 (SR45.2) that replaces a single arginine with eight amino acids (TSPQRKTG). The biological implications of SR45 alternative splicing have been unclear. A previously described loss-of-function mutant affecting both isoforms, sr45-1, shows several developmental defects, including defects in petal development and root growth. We found that the SR45 promoter is highly active in regions with actively growing and dividing cells. We also tested the ability of each SR45 isoform to complement the sr45-1 mutant by overexpression of isoform-specific green fluorescent protein (GFP) fusion proteins. As expected, transgenic plants overexpressing either isoform displayed both nuclear speckles and GFP fluorescence throughout the nucleoplasm. We found that SR45.1-GFP complements the flower petal phenotype, but not the root growth phenotype. Conversely, SR45.2-GFP complements root growth but not floral morphology. Mutation of a predicted phosphorylation site within the alternatively spliced segment, SR45.1-S219A-GFP, does not affect complementation. However, a double mutation affecting both serine-219 and the adjacent threonine-218 (SR45.1-T218A + S219A-GFP) behaves like isoform 2, complementing the root but not the floral phenotype. In conclusion, our study provides evidence that the two alternatively spliced isoforms of SR45 have distinct biological functions.
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Affiliation(s)
- Xiao-Ning Zhang
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20740, USA
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37
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Schöning JC, Streitner C, Meyer IM, Gao Y, Staiger D. Reciprocal regulation of glycine-rich RNA-binding proteins via an interlocked feedback loop coupling alternative splicing to nonsense-mediated decay in Arabidopsis. Nucleic Acids Res 2008; 36:6977-87. [PMID: 18987006 PMCID: PMC2602770 DOI: 10.1093/nar/gkn847] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Arabidopsis RNA-binding protein AtGRP8 undergoes negative autoregulation at the post-transcriptional level. An elevated AtGRP8 protein level promotes the use of a cryptic 5' splice site to generate an alternatively spliced transcript, as_AtGRP8, retaining the 5' half of the intron with a premature termination codon. In mutants defective in nonsense-mediated decay (NMD) abundance of as_AtGRP8 but not its pre-mRNA is elevated, indicating that as_AtGRP8 is a direct NMD target, thus limiting the production of functional AtGRP8 protein. In addition to its own pre-mRNA, AtGRP8 negatively regulates the AtGRP7 transcript through promoting the formation of the equivalent alternatively spliced as_AtGRP7 transcript, leading to a decrease in AtGRP7 abundance. Recombinant AtGRP8 binds to its own and the AtGRP7 pre-mRNA, suggesting that this interaction is relevant for the splicing decision in vivo. AtGRP7 itself is part of a negative autoregulatory circuit that influences circadian oscillations of its own and the AtGRP8 transcript through alternative splicing linked to NMD. Thus, we identify an interlocked feedback loop through which two RNA-binding proteins autoregulate and reciprocally crossregulate by coupling unproductive splicing to NMD. A high degree of evolutionary sequence conservation in the introns retained in as_AtGRP8 or as_AtGRP7 points to an important function of these sequences.
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Affiliation(s)
- Jan C Schöning
- Molecular Cell Physiology, Bielefeld University, Bielefeld, Germany
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38
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Abstract
The spliceosome is a large nuclear structure consisting of dynamically interacting RNAs and proteins. This chapter briefly reviews some of the known components and their interactions. Large-scale proteomics and gene expression studies may be required to unravel the many intricate mechanisms involved in splice site recognition and selection.
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Abstract
A substantial fraction (approximately 30%) of plant genes is alternatively spliced, but how alternative splicing is regulated remains unknown. Many plant genes undergo alternative splicing in response to a variety of stresses. Large-scale computational analyses and experimental approaches focused on select genes are beginning to reveal that alternative splicing constitutes an integral part of gene regulation in stress responses. Based on the studies discussed in this chapter, it appears that alternative splicing generates transcriptome/proteome complexity that is likely to be important for stress adaptation. However, the signaling pathways that relay stress conditions to splicing machinery and if and how the alternative spliced products confer adaptive advantages to plants are poorly understood.
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40
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Alternative splicing at NAGNAG acceptors in Arabidopsis thaliana SR and SR-related protein-coding genes. BMC Genomics 2008; 9:159. [PMID: 18402682 PMCID: PMC2375911 DOI: 10.1186/1471-2164-9-159] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Accepted: 04/10/2008] [Indexed: 11/10/2022] Open
Abstract
Background Several recent studies indicate that alternative splicing in Arabidopsis and other plants is a common mechanism for post-transcriptional modulation of gene expression. However, few analyses have been done so far to elucidate the functional relevance of alternative splicing in higher plants. Representing a frequent and universal subtle alternative splicing event among eukaryotes, alternative splicing at NAGNAG acceptors contributes to transcriptome diversity and therefore, proteome plasticity. Alternatively spliced NAGNAG acceptors are overrepresented in genes coding for proteins with RNA-recognition motifs (RRMs). As SR proteins, a family of RRM-containing important splicing factors, are known to be extensively alternatively spliced in Arabidopsis, we analyzed alternative splicing at NAGNAG acceptors in SR and SR-related genes. Results In a comprehensive analysis of the Arabidopsis thaliana genome, we identified 6,772 introns that exhibit a NAGNAG acceptor motif. Alternative splicing at these acceptors was assessed using available EST data, complemented by a sequence-based prediction method. Of the 36 identified introns within 30 SR and SR-related protein-coding genes that have a NAGNAG acceptor, we selected 15 candidates for an experimental analysis of alternative splicing under several conditions. We provide experimental evidence for 8 of these candidates being alternatively spliced. Quantifying the ratio of NAGNAG-derived splice variants under several conditions, we found organ-specific splicing ratios in adult plants and changes in seedlings of different ages. Splicing ratio changes were observed in response to heat shock and most strikingly, cold shock. Interestingly, the patterns of differential splicing ratios are similar for all analyzed genes. Conclusion NAGNAG acceptors frequently occur in the Arabidopsis genome and are particularly prevalent in SR and SR-related protein-coding genes. A lack of extensive EST coverage can be compensated by using the proposed sequence-based method to predict alternative splicing at these acceptors. Our findings indicate that the differential effects on NAGNAG alternative splicing in SR and SR-related genes are organ- and condition-specific rather than gene-specific.
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Simpson CG, Fuller J, Maronova M, Kalyna M, Davidson D, McNicol J, Barta A, Brown JWS. Monitoring changes in alternative precursor messenger RNA splicing in multiple gene transcripts. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 53:1035-48. [PMID: 18088312 DOI: 10.1111/j.1365-313x.2007.03392.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Alternative splicing (AS) increases the proteomic and functional capacity of genomes through the generation of alternative mRNA transcripts from the same gene. AS is now estimated to occur in a third of Arabidopsis and rice genes, and includes genes involved in the control of growth and development, responses to stress and signalling. Regulation of AS reflects the interactions between positive and negative cis sequences in the precursor messenger RNA and a range of trans-acting factors. The levels and activities of these factors differ in different cells and growth conditions. To identify changes in AS in multiple genes simultaneously, we have established a reproducible RT-PCR panel that can analyse 96 alternative splicing events and accurately measure the ratio of alternatively spliced products. This procedure detected statistically significant changes in AS in different plant organs, in plants grown under different light and day-length conditions, and in plants overexpressing splicing factors. The system provides a convenient, medium-throughput means of monitoring changes in AS in multiple genes. It can readily be applied to much larger or targeted sets of gene transcripts to generate information on the significance and regulation of AS in plant growth and development, specific processes and responses to external stimuli.
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Abstract
SR proteins are a family of splicing factors important for splice site recognition and spliceosome assembly. Their ability to bind to RNA and to interact with proteins as well identifies them as important players in splice site choice and alternative splicing. Plants possess twice as many SR proteins as animals, and some of the subfamilies are plant specific. Arabidopsis SR proteins are involved in different aspects of plant growth and development as well as in responses to environmental cues. The plant-specific subfamilies have been shown to be regulated by alternative splicing events, which are highly conserved in evolution. The tight regulation of splicing factors by alternative splicing might allow coordinated responses of their target genes.
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Goetz M, Hooper LC, Johnson SD, Rodrigues JCM, Vivian-Smith A, Koltunow AM. Expression of aberrant forms of AUXIN RESPONSE FACTOR8 stimulates parthenocarpy in Arabidopsis and tomato. PLANT PHYSIOLOGY 2007; 145:351-66. [PMID: 17766399 PMCID: PMC2048734 DOI: 10.1104/pp.107.104174] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Accepted: 08/22/2007] [Indexed: 05/17/2023]
Abstract
Fruit initiation in Arabidopsis (Arabidopsis thaliana) is generally repressed until fertilization occurs. However, mutations in AUXIN RESPONSE FACTOR8 (ARF8) uncouple fruit initiation from fertilization, resulting in the formation of seedless, parthenocarpic fruit. Here we induced parthenocarpy in wild-type Arabidopsis by introducing either the mutant genomic (g) Atarf8-4 sequence or gAtARF8:beta-glucuronidase translational fusion constructs by plant transformation. Silencing of endogenous AtARF8 transcription was not observed, indicating that the introduced, aberrant ARF8 transcripts were compromising the function of endogenous ARF8 and/or associated factors involved in suppressing fruit initiation. To analyze the role of ARF8 in tomato (Solanum lycopersicum) we initially emasculated 23 tomato cultivars to test for background parthenocarpy. Surprisingly, all had a predisposition to initiate fertilization-independent fruit growth. Expression of gAtarf8-4 in transgenic tomato ('Monalbo') resulted in a significant increase in the number and size of parthenocarpic fruit. Isolation of tomato ARF8 cDNA indicated significant sequence conservation with AtARF8. SlARF8 may therefore control tomato fruit initiation in a similar manner as AtARF8 does in Arabidopsis. Two SlARF8 cDNAs differing in size by 5 bp were found, both arising from the same gene. The smaller cDNA is a splice variant and is also present in Arabidopsis. We propose that low endogenous levels of the splice variant products might interfere with efficient formation/function of a complex repressing fruit initiation, thereby providing an explanation for the observed ovary expansion in tomato and also Arabidopsis after emasculation. Increasing the levels of aberrant Atarf8-4 transcripts may further destabilize formation/function of the complex in a dosage-dependent manner enhancing tomato parthenocarpic fruit initiation frequency and size and mimicking the parthenocarpic dehiscent silique phenotype found in homozygous Atarf8-4 mutants. Collectively these data suggest that similar mechanisms involving auxin signaling exist to inhibit parthenocarpic fruit set in tomato and Arabidopsis.
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Affiliation(s)
- Marc Goetz
- Commonwealth Scientific and Industrial Research Organization, Plant Industry, Glen Osmond, South Australia 5064, Australia
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44
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Tanabe N, Yoshimura K, Kimura A, Yabuta Y, Shigeoka S. Differential expression of alternatively spliced mRNAs of Arabidopsis SR protein homologs, atSR30 and atSR45a, in response to environmental stress. PLANT & CELL PHYSIOLOGY 2007; 48:1036-49. [PMID: 17556373 DOI: 10.1093/pcp/pcm069] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Serine/arginine-rich (SR) proteins are associated with either the regulation or the execution of both constitutive splicing and the selection of alternative splice sites in animals and plants. We demonstrated the molecular characterization of a homolog of SR protein, atSR45a, in Arabidopsis plants. Six types of mRNA variants (atSR45a-1a-e and atSR45a-2) were generated by the alternative selection of transcriptional initiation sites and the alternative splicing of introns in atSR45a pre-mRNA. The atSR45a-1a and -2 proteins, presumed mature forms, were located in the nucleus and interacted with U1-70K, suggesting that these proteins function as a splicing factor in Arabidopsis. The levels of the transcripts atSR45a and atSR30, SF2/ASF-like SR proteins, were increased by various types of stress, such as high-light irradiation and salinity. Furthermore, the splicing patterns of atSR45a and atSR30 pre-mRNA themselves were altered under these stressful conditions. In particular, the expression of atSR45a-1a, atSR45a-2, atSR30 mRNA1 and atSR30 mRNA3 was greatly increased by high-light irradiation. These results indicate that the regulation of transcription and alternative splicing of atSR45a and atSR30 is responsive to various stressful conditions.
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Affiliation(s)
- Noriaki Tanabe
- Advanced Bioscience, Graduate School, Kinki University, 3327-204 Nakamachi, Nara, 631-8505 Japan
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45
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Abstract
AbstractAlternative splicing is an important cellular mechanism that increases the diversity of gene products. The study of alternatively spliced genes reported so far in plants is far less documented than that in mammals, but considerable results have been reported, showing the role of these genes in regulating mechanisms, influencing factors, and specificities and function of alternative splicing in plants. This review summarizes briefly the major progress made on alternative splicing in plants.
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Ali GS, Palusa SG, Golovkin M, Prasad J, Manley JL, Reddy AS. Regulation of plant developmental processes by a novel splicing factor. PLoS One 2007; 2:e471. [PMID: 17534421 PMCID: PMC1868597 DOI: 10.1371/journal.pone.0000471] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Accepted: 04/28/2007] [Indexed: 11/18/2022] Open
Abstract
Serine/arginine-rich (SR) proteins play important roles in constitutive and alternative splicing and other aspects of mRNA metabolism. We have previously isolated a unique plant SR protein (SR45) with atypical domain organization. However, the biological and molecular functions of this novel SR protein are not known. Here, we report biological and molecular functions of this protein. Using an in vitro splicing complementation assay, we showed that SR45 functions as an essential splicing factor. Furthermore, the alternative splicing pattern of transcripts of several other SR genes was altered in a mutant, sr45-1, suggesting that the observed phenotypic abnormalities in sr45-1 are likely due to altered levels of SR protein isoforms, which in turn modulate splicing of other pre-mRNAs. sr45-1 exhibited developmental abnormalities, including delayed flowering, narrow leaves and altered number of petals and stamens. The late flowering phenotype was observed under both long days and short days and was rescued by vernalization. FLC, a key flowering repressor, is up-regulated in sr45-1 demonstrating that SR45 influences the autonomous flowering pathway. Changes in the alternative splicing of SR genes and the phenotypic defects in the mutant were rescued by SR45 cDNA, further confirming that the observed defects in the mutant are due to the lack of SR45. These results indicate that SR45 is a novel plant-specific splicing factor that plays a crucial role in regulating developmental processes.
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Affiliation(s)
- Gul Shad Ali
- Department of Biology and Program in Molecular Plant Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Saiprasad G. Palusa
- Department of Biology and Program in Molecular Plant Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Maxim Golovkin
- Department of Biology and Program in Molecular Plant Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Jayendra Prasad
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - James L. Manley
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - Anireddy S.N. Reddy
- Department of Biology and Program in Molecular Plant Biology, Colorado State University, Fort Collins, Colorado, United States of America
- * To whom correspondence should be addressed. E-mail:
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Pertea M, Mount SM, Salzberg SL. A computational survey of candidate exonic splicing enhancer motifs in the model plant Arabidopsis thaliana. BMC Bioinformatics 2007; 8:159. [PMID: 17517127 PMCID: PMC1892810 DOI: 10.1186/1471-2105-8-159] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Accepted: 05/21/2007] [Indexed: 02/05/2023] Open
Abstract
Background Algorithmic approaches to splice site prediction have relied mainly on the consensus patterns found at the boundaries between protein coding and non-coding regions. However exonic splicing enhancers have been shown to enhance the utilization of nearby splice sites. Results We have developed a new computational technique to identify significantly conserved motifs involved in splice site regulation. First, 84 putative exonic splicing enhancer hexamers are identified in Arabidopsis thaliana. Then a Gibbs sampling program called ELPH was used to locate conserved motifs represented by these hexamers in exonic regions near splice sites in confirmed genes. Oligomers containing 35 of these motifs have been shown experimentally to induce significant inclusion of A. thaliana exons. Second, integration of our regulatory motifs into two different splice site recognition programs significantly improved the ability of the software to correctly predict splice sites in a large database of confirmed genes. We have released GeneSplicerESE, the improved splice site recognition code, as open source software. Conclusion Our results show that the use of the ESE motifs consistently improves splice site prediction accuracy.
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Affiliation(s)
- Mihaela Pertea
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD 20742, USA.
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Palusa SG, Ali GS, Reddy ASN. Alternative splicing of pre-mRNAs of Arabidopsis serine/arginine-rich proteins: regulation by hormones and stresses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2007; 49:1091-107. [PMID: 17319848 DOI: 10.1111/j.1365-313x.2006.03020.x] [Citation(s) in RCA: 283] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Precursor mRNAs with introns can undergo alternative splicing (AS) to produce structurally and functionally different proteins from the same gene. Here, we show that the pre-mRNAs of Arabidopsis genes that encode serine/arginine-rich (SR) proteins, a conserved family of splicing regulators in eukaryotes, are extensively alternatively spliced. Remarkably about 95 transcripts are produced from only 15 genes, thereby increasing the complexity of the SR gene family transcriptome by six-fold. The AS of some SR genes is controlled in a developmental and tissue-specific manner. Interestingly, among the various hormones and abiotic stresses tested, temperature stress (cold and heat) dramatically altered the AS of pre-mRNAs of several SR genes, whereas hormones altered the splicing of only three SR genes. These results indicate that abiotic stresses regulate the AS of the pre-mRNAs of SR genes to produce different isoforms of SR proteins that are likely to have altered function(s) in pre-mRNA splicing. Sequence analysis of splice variants revealed that predicted proteins from a majority of these variants either lack one or more modular domains or contain truncated domains. Because of the modular nature of the various domains in SR proteins, the proteins produced from splice variants are likely to have distinct functions. Together our results indicate that Arabidopsis SR genes generate surprisingly large transcriptome complexity, which is altered by stresses and hormones.
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Reddy ASN. Alternative splicing of pre-messenger RNAs in plants in the genomic era. ANNUAL REVIEW OF PLANT BIOLOGY 2007; 58:267-94. [PMID: 17222076 DOI: 10.1146/annurev.arplant.58.032806.103754] [Citation(s) in RCA: 208] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Primary transcripts (precursor-mRNAs) with introns can undergo alternative splicing to produce multiple transcripts from a single gene by differential use of splice sites, thereby increasing the transcriptome and proteome complexity within and between cells and tissues. Alternative splicing in plants is largely an unexplored area of gene expression, as this phenomenon used to be considered rare. However, recent genome-wide computational analyses have revealed that alternative splicing in flowering plants is far more prevalent than previously thought. Interestingly, pre-mRNAs of many spliceosomal proteins, especially serine/arginine-rich (SR) proteins, are extensively alternatively spliced. Furthermore, stresses have a dramatic effect on alternative splicing of pre-mRNAs including those that encode many spliceosomal proteins. Although the mechanisms that regulate alternative splicing in plants are largely unknown, several reports strongly suggest a key role for SR proteins in spliceosome assembly and regulated splicing. Recent studies suggest that alternative splicing in plants is an important posttranscriptional regulatory mechanism in modulating gene expression and eventually plant form and function.
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Affiliation(s)
- Anireddy S N Reddy
- Department of Biology and Program in Molecular Plant Biology, Colorado State University, Fort Collins, CO 80523, USA.
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Tillemans V, Leponce I, Rausin G, Dispa L, Motte P. Insights into nuclear organization in plants as revealed by the dynamic distribution of Arabidopsis SR splicing factors. THE PLANT CELL 2006; 18:3218-34. [PMID: 17114353 PMCID: PMC1693954 DOI: 10.1105/tpc.106.044529] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Serine/arginine-rich (SR) proteins are splicing regulators that share a modular structure consisting of one or two N-terminal RNA recognition motif domains and a C-terminal RS-rich domain. We investigated the dynamic localization of the Arabidopsis thaliana SR protein RSZp22, which, as we showed previously, distributes in predominant speckle-like structures and in the nucleolus. To determine the role of RSZp22 diverse domains in its nucleolar distribution, we investigated the subnuclear localization of domain-deleted mutant proteins. Our results suggest that the nucleolar localization of RSZp22 does not depend on a single targeting signal but likely involves different domains/motifs. Photobleaching experiments demonstrated the unrestricted dynamics of RSZp22 between nuclear compartments. Selective inhibitor experiments of ongoing cellular phosphorylation influenced the rates of exchange of RSZp22 between the different nuclear territories, indicating that SR protein mobility is dependent on the phosphorylation state of the cell. Furthermore, based on a leptomycin B- and fluorescence loss in photobleaching-based sensitive assay, we suggest that RSZp22 is a nucleocytoplasmic shuttling protein. Finally, with electron microscopy, we confirmed that RSp31, a plant-specific SR protein, is dynamically distributed in nucleolar cap-like structures upon phosphorylation inhibition. Our findings emphasize the high mobility of Arabidopsis SR splicing factors and provide insights into the dynamic relationships between the different nuclear compartments.
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Affiliation(s)
- Vinciane Tillemans
- Laboratory of Plant Cell and Molecular Biology, Department of Life Sciences, Institute of Botany, University of Liège, B-4000 Liège, Belgium
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