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Sybilska E, Collin A, Sadat Haddadi B, Mur LAJ, Beckmann M, Guo W, Simpson CG, Daszkowska-Golec A. The cap-binding complex modulates ABA-responsive transcript splicing during germination in barley (Hordeum vulgare). Sci Rep 2024; 14:18278. [PMID: 39107424 PMCID: PMC11303550 DOI: 10.1038/s41598-024-69373-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 08/05/2024] [Indexed: 08/10/2024] Open
Abstract
To decipher the molecular bases governing seed germination, this study presents the pivotal role of the cap-binding complex (CBC), comprising CBP20 and CBP80, in modulating the inhibitory effects of abscisic acid (ABA) in barley. Using both single and double barley mutants in genes encoding the CBC, we revealed that the double mutant hvcbp20.ab/hvcbp80.b displays ABA insensitivity, in stark contrast to the hypersensitivity observed in single mutants during germination. Our comprehensive transcriptome and metabolome analysis not only identified significant alterations in gene expression and splicing patterns but also underscored the regulatory nexus among CBC, ABA, and brassinosteroid (BR) signaling pathways.
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Affiliation(s)
- Ewa Sybilska
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Jagiellońska 28, 40-032, Katowice, Poland
| | - Anna Collin
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Jagiellońska 28, 40-032, Katowice, Poland
| | | | - Luis A J Mur
- Department of Life Science, Aberystwyth University, Aberystwyth, UK
| | - Manfred Beckmann
- Department of Life Science, Aberystwyth University, Aberystwyth, UK
| | - Wenbin Guo
- Information and Computational Sciences, James Hutton Institute, Dundee, DD2 5DA, Scotland, UK
| | - Craig G Simpson
- Cell and Molecular Sciences, James Hutton Institute, Dundee, DD2 5DA, Scotland, UK
| | - Agata Daszkowska-Golec
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Jagiellońska 28, 40-032, Katowice, Poland.
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2
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Fanara S, Schloesser M, Joris M, De Franco S, Vandevenne M, Kerff F, Hanikenne M, Motte P. The Arabidopsis SR45 splicing factor bridges the splicing machinery and the exon-exon junction complex. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2280-2298. [PMID: 38180875 DOI: 10.1093/jxb/erae002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 01/04/2024] [Indexed: 01/07/2024]
Abstract
The Arabidopsis splicing factor serine/arginine-rich 45 (SR45) contributes to several biological processes. The sr45-1 loss-of-function mutant exhibits delayed root development, late flowering, unusual numbers of floral organs, shorter siliques with decreased seed sets, narrower leaves and petals, and altered metal distribution. SR45 bears a unique RNA recognition motif (RRM) flanked by one serine/arginine-rich (RS) domain on both sides. Here, we studied the function of each SR45 domains by examining their involvement in: (i) the spatial distribution of SR45; (ii) the establishment of a protein-protein interaction network including spliceosomal and exon-exon junction complex (EJC) components; and (iii) the RNA binding specificity. We report that the endogenous SR45 promoter is active during vegetative and reproductive growth, and that the SR45 protein localizes in the nucleus. We demonstrate that the C-terminal arginine/serine-rich domain is a determinant of nuclear localization. We show that the SR45 RRM domain specifically binds purine-rich RNA motifs via three residues (H101, H141, and Y143), and is also involved in protein-protein interactions. We further show that SR45 bridges both mRNA splicing and surveillance machineries as a partner of EJC core components and peripheral factors, which requires phosphoresidues probably phosphorylated by kinases from both the CLK and SRPK families. Our findings provide insights into the contribution of each SR45 domain to both spliceosome and EJC assemblies.
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Affiliation(s)
- Steven Fanara
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000, Liège, Belgium
| | - Marie Schloesser
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000, Liège, Belgium
| | - Marine Joris
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000, Liège, Belgium
| | - Simona De Franco
- InBioS-Center for Protein Engineering, Laboratory of Biological Macromolecules, University of Liège, 4000, Liège, Belgium
| | - Marylène Vandevenne
- InBioS-Center for Protein Engineering, Laboratory of Biological Macromolecules, University of Liège, 4000, Liège, Belgium
| | - Frédéric Kerff
- InBioS-Center for Protein Engineering, Laboratory of Crystallography, University of Liège, 4000, Liège, Belgium
| | - Marc Hanikenne
- InBioS-PhytoSystems, Translational Plant Biology, University of Liège, 4000, Liège, Belgium
| | - Patrick Motte
- InBioS-PhytoSystems, Functional Genomics and Plant Molecular Imaging, University of Liège, 4000, Liège, Belgium
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3
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Li Y, Gao J, Wang Y, Cai J, Wu D, Wang L, Pu W, Yu F, Zhu S. The functions of a 5' tRNA-Ala-derived fragment in gene expression. PLANT PHYSIOLOGY 2023; 193:1126-1141. [PMID: 37350495 DOI: 10.1093/plphys/kiad361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 05/04/2023] [Accepted: 05/22/2023] [Indexed: 06/24/2023]
Abstract
Transfer RNA (tRNA) can produce smaller RNA fragments called tRNA-derived fragments (tRFs). tRFs play critical roles in multiple cellular programs, although the functional mechanisms of tRFs remain largely unknown in plants. In this study, we examined the phenotype associated with 5' tRF-Ala (tRF-Ala, produced from tRNA-Ala) overexpression and knockdown lines (tDR-Ala-OE and tDR-Ala-kd, respectively) and the mechanisms by which tRF-Ala affects mRNA levels in Arabidopsis (Arabidopsis thaliana). We investigated the candidate proteins associated with tRF-Ala by quantitative proteomics and confirmed the direct interaction between tRF-Ala and the splicing factor SERINE-ARGININE RICH PROTEIN 34 (SR34). A transcriptome sequencing analysis showed that 318 genes among all the genes (786) with substantial alternative splicing (AS) variance in tDR-Ala-OE lines are targets of SR34. tRF-Ala diminished the binding affinity between SR34 and its targets by direct competition for interaction with SR34. These findings reveal the critical roles of tRF-Ala in regulating mRNA levels and splicing.
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Affiliation(s)
- Yuanyuan Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
| | - Junping Gao
- Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China
| | - Ying Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
| | - Jun Cai
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
| | - Dousheng Wu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
| | - Long Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
| | - Wenxuan Pu
- Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China
| | - Feng Yu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
| | - Sirui Zhu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, China
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4
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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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5
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Jung H, Park HJ, Jo SH, Lee A, Lee HJ, Kim HS, Jung C, Cho HS. Nuclear OsFKBP20-1b maintains SR34 stability and promotes the splicing of retained introns upon ABA exposure in rice. THE NEW PHYTOLOGIST 2023; 238:2476-2494. [PMID: 36942934 DOI: 10.1111/nph.18892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/16/2023] [Indexed: 05/19/2023]
Abstract
Alternative splicing (AS) is a critical means by which plants respond to changes in the environment, but few splicing factors contributing to AS have been reported and functionally characterized in rice (Oryza sativa L.). Here, we explored the function and molecular mechanism of the spliceosome-associated protein OsFKBP20-1b during AS. We determined the AS landscape of wild-type and osfkbp20-1b knockout plants upon abscisic acid (ABA) treatment by transcriptome deep sequencing. To capture the dynamics of translating intron-containing mRNAs, we blocked transcription with cordycepin and performed polysome profiling. We also analyzed whether OsFKBP20-1b and the splicing factors OsSR34 and OsSR45 function together in AS using protoplast transfection assays. We show that OsFKBP20-1b interacts with OsSR34 and regulates its stability, suggesting a role as a chaperone-like protein in the spliceosome. OsFKBP20-1b facilitates the splicing of mRNAs with retained introns after ABA treatment; some of these mRNAs are translatable and encode functional transcriptional regulators of stress-responsive genes. In addition, interacting proteins, OsSR34 and OsSR45, regulate the splicing of the same retained introns as OsFKBP20-1b after ABA treatment. Our findings reveal that spliceosome-associated immunophilin functions in alternative RNA splicing in rice by positively regulating the splicing of retained introns to limit ABA response.
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Affiliation(s)
- Haemyeong Jung
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Hyun Ji Park
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
| | - Seung Hee Jo
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Areum Lee
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Hyo-Jun Lee
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Functional Genomics, KRIBB School of Bioscience, UST, Daejeon, 34113, South Korea
| | - Hyun-Soon Kim
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Choonkyun Jung
- Department of International Agricultural Technology and Crop Biotechnology Institute/Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, South Korea
- Department of Agriculture, Forestry, and Bioresources and Integrated Major in Global Smart Farm, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Hye Sun Cho
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
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Jia ZC, Das D, Zhang Y, Fernie AR, Liu YG, Chen M, Zhang J. Plant serine/arginine-rich proteins: versatile players in RNA processing. PLANTA 2023; 257:109. [PMID: 37145304 DOI: 10.1007/s00425-023-04132-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 04/05/2023] [Indexed: 05/06/2023]
Abstract
MAIN CONCLUSION Serine/arginine-rich (SR) proteins participate in RNA processing by interacting with precursor mRNAs or other splicing factors to maintain plant growth and stress responses. Alternative splicing is an important mechanism involved in mRNA processing and regulation of gene expression at the posttranscriptional level, which is the main reason for the diversity of genes and proteins. The process of alternative splicing requires the participation of many specific splicing factors. The SR protein family is a splicing factor in eukaryotes. The vast majority of SR proteins' existence is an essential survival factor. Through its RS domain and other unique domains, SR proteins can interact with specific sequences of precursor mRNA or other splicing factors and cooperate to complete the correct selection of splicing sites or promote the formation of spliceosomes. They play essential roles in the composition and alternative splicing of precursor mRNAs, providing pivotal functions to maintain growth and stress responses in animals and plants. Although SR proteins have been identified in plants for three decades, their evolutionary trajectory, molecular function, and regulatory network remain largely unknown compared to their animal counterparts. This article reviews the current understanding of this gene family in eukaryotes and proposes potential key research priorities for future functional studies.
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Affiliation(s)
- Zi-Chang Jia
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guiyang, 550025, China
| | - Debatosh Das
- College of Agriculture, Food and Natural Resources (CAFNR), Division of Plant Sciences and Technology, 52 Agricultural Building, University of Missouri, Columbia, MO, 65201, USA
- Department of Biology, Hong Kong Baptist University, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Youjun Zhang
- Center of Plant System Biology and Biotechnology, 4000, Plovdiv, Bulgaria
- Max-Planck-Institut Für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
| | - Alisdair R Fernie
- Center of Plant System Biology and Biotechnology, 4000, Plovdiv, Bulgaria
- Max-Planck-Institut Für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
| | - Ying-Gao Liu
- State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Taian, Shandong, China
| | - Moxian Chen
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guiyang, 550025, China.
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Jianhua Zhang
- Department of Biology, Hong Kong Baptist University, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong.
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7
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Kumar K, Sinha SK, Maity U, Kirti PB, Kumar KRR. Insights into established and emerging roles of SR protein family in plants and animals. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1763. [PMID: 36131558 DOI: 10.1002/wrna.1763] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 08/11/2022] [Accepted: 08/22/2022] [Indexed: 05/13/2023]
Abstract
Splicing of pre-mRNA is an essential part of eukaryotic gene expression. Serine-/arginine-rich (SR) proteins are highly conserved RNA-binding proteins present in all metazoans and plants. SR proteins are involved in constitutive and alternative splicing, thereby regulating the transcriptome and proteome diversity in the organism. In addition to their role in splicing, SR proteins are also involved in mRNA export, nonsense-mediated mRNA decay, mRNA stability, and translation. Due to their pivotal roles in mRNA metabolism, SR proteins play essential roles in normal growth and development. Hence, any misregulation of this set of proteins causes developmental defects in both plants and animals. SR proteins from the animal kingdom are extensively studied for their canonical and noncanonical functions. Compared with the animal kingdom, plant genomes harbor more SR protein-encoding genes and greater diversity of SR proteins, which are probably evolved for plant-specific functions. Evidence from both plants and animals confirms the essential role of SR proteins as regulators of gene expression influencing cellular processes, developmental stages, and disease conditions. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
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Affiliation(s)
- Kundan Kumar
- Department of Biotechnology, Indira Gandhi National Tribal University (IGNTU), Amarkantak, India
| | - Shubham Kumar Sinha
- Department of Biotechnology, Indira Gandhi National Tribal University (IGNTU), Amarkantak, India
| | - Upasana Maity
- Department of Biotechnology, Indira Gandhi National Tribal University (IGNTU), Amarkantak, India
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8
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Edris S, Abulfaraj AA, Makki RM, Abo-Aba S, Algandaby MM, Sabir J, Jansen RK, El Domyati FM, Bahieldin A. Early Fruit Development Regulation-Related Genes Concordantly Expressed with TCP Transcription Factors in Tomato (Solanum lycopersicum). Curr Issues Mol Biol 2023; 45:2372-2380. [PMID: 36975523 PMCID: PMC10099719 DOI: 10.3390/cimb45030153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/15/2023] [Accepted: 02/20/2023] [Indexed: 03/14/2023] Open
Abstract
The tomato (Solanum lycopersicum L.) is considered one of the most important vegetable crops globally, both agronomically and economically; however, its fruit development regulation network is still unclear. The transcription factors serve as master regulators, activating many genes and/or metabolic pathways throughout the entire plant life cycle. In this study, we identified the transcription factors that are coordinated with TCP gene family regulation in early fruit development by making use of the high-throughput sequencing of RNA (RNAseq) technique. A total of 23 TCP-encoding genes were found to be regulated at various stages during the growth of the fruit. The expression patterns of five TCPs were consistent with those of other transcription factors and genes. There are two unique subgroups of this larger family: class I and class II TCPs. Others were directly associated with the growth and/or ripening of fruit, while others were involved in the production of the hormone auxin. Moreover, it was discovered that TCP18 had an expression pattern that was similar to that of the ethylene-responsive transcription factor 4 (ERF4). Tomato fruit set and overall development are under the direction of a gene called auxin response factor 5 (ARF5). TCP15 revealed an expression that was in sync with this gene. This study provides insight into the potential processes that help in acquiring superior fruit qualities by accelerating fruit growth and ripening.
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Affiliation(s)
- Sherif Edris
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders (PACER-HD), Faculty of Medicine, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo 11241, Egypt
- R&D Department, Al Borg Diagnostics, Jeddah 23514, Saudi Arabia
- Correspondence: ; Tel.: +966-59-366-2384
| | - Aala A. Abulfaraj
- Biological Sciences Department, College of Science & Arts, King Abdulaziz University, Rabigh 21911, Saudi Arabia
| | - Rania M. Makki
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Salah Abo-Aba
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- National Research Centre, Department of Microbial Genetics, Genetic Engineering and Biotechnology Division, Giza 12622, Egypt
| | - Mardi M. Algandaby
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Jamal Sabir
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Robert K. Jansen
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Fotouh M. El Domyati
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo 11241, Egypt
| | - Ahmed Bahieldin
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo 11241, Egypt
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9
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Parakkunnel R, Naik K B, Vanishree G, C S, Purru S, Bhaskar K U, Bhat KV, Kumar S. Gene fusions, micro-exons and splice variants define stress signaling by AP2/ERF and WRKY transcription factors in the sesame pan-genome. FRONTIERS IN PLANT SCIENCE 2022; 13:1076229. [PMID: 36618639 PMCID: PMC9817154 DOI: 10.3389/fpls.2022.1076229] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Evolutionary dynamics of AP2/ERF and WRKY genes, the major components of defense response were studied extensively in the sesame pan-genome. Massive variation was observed for gene copy numbers, genome location, domain structure, exon-intron structure and protein parameters. In the pan-genome, 63% of AP2/ERF members were devoid of introns whereas >99% of WRKY genes contained multiple introns. AP2 subfamily was found to be micro-exon rich with the adjoining intronic sequences sharing sequence similarity to many stress-responsive and fatty acid metabolism genes. WRKY family included extensive multi-domain gene fusions where the additional domains significantly enhanced gene and exonic sizes as well as gene copy numbers. The fusion genes were found to have roles in acquired immunity, stress response, cell and membrane integrity as well as ROS signaling. The individual genomes shared extensive synteny and collinearity although ecological adaptation was evident among the Chinese and Indian accessions. Significant positive selection effects were noticed for both micro-exon and multi-domain genes. Splice variants with changes in acceptor, donor and branch sites were common and 6-7 splice variants were detected per gene. The study ascertained vital roles of lipid metabolism and chlorophyll biosynthesis in the defense response and stress signaling pathways. 60% of the studied genes localized in the nucleus while 20% preferred chloroplast. Unique cis-element distribution was noticed in the upstream promoter region with MYB and STRE in WRKY genes while MYC was present in the AP2/ERF genes. Intron-less genes exhibited great diversity in the promoter sequences wherein the predominance of dosage effect indicated variable gene expression levels. Mimicking the NBS-LRR genes, a chloroplast localized WRKY gene, Swetha_24868, with additional domains of chorismate mutase, cAMP and voltage-dependent potassium channel was found to act as a master regulator of defense signaling, triggering immunity and reducing ROS levels.
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Affiliation(s)
- Ramya Parakkunnel
- ICAR- Indian Institute of Seed Science, Regional Station, Gandhi Krishi Vigyana Kendra (GKVK) Campus, Bengaluru, India
| | - Bhojaraja Naik K
- ICAR- Indian Institute of Seed Science, Regional Station, Gandhi Krishi Vigyana Kendra (GKVK) Campus, Bengaluru, India
| | - Girimalla Vanishree
- ICAR- Indian Institute of Seed Science, Regional Station, Gandhi Krishi Vigyana Kendra (GKVK) Campus, Bengaluru, India
| | - Susmita C
- ICAR- Indian Institute of Seed Science, Mau, Uttar Pradesh, India
| | - Supriya Purru
- ICAR- National Academy of Agricultural Research Management, Hyderabad, Telengana, India
| | - Udaya Bhaskar K
- ICAR- Indian Institute of Seed Science, Regional Station, Gandhi Krishi Vigyana Kendra (GKVK) Campus, Bengaluru, India
| | - KV. Bhat
- Division of Genomic Resources, ICAR- National Bureau of Plant Genetic Resources, New Delhi, India
| | - Sanjay Kumar
- ICAR- Indian Institute of Seed Science, Mau, Uttar Pradesh, India
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10
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Jin X. Regulatory Network of Serine/Arginine-Rich (SR) Proteins: The Molecular Mechanism and Physiological Function in Plants. Int J Mol Sci 2022; 23:ijms231710147. [PMID: 36077545 PMCID: PMC9456285 DOI: 10.3390/ijms231710147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/10/2022] [Accepted: 08/29/2022] [Indexed: 12/05/2022] Open
Abstract
Serine/arginine-rich (SR) proteins are a type of splicing factor. They play significant roles in constitutive and alternative pre-mRNA splicing, and are involved in post-splicing activities, such as mRNA nuclear export, nonsense-mediated mRNA decay, mRNA translation, and miRNA biogenesis. In plants, SR proteins function under a complex regulatory network by protein–protein and RNA–protein interactions between SR proteins, other splicing factors, other proteins, or even RNAs. The regulatory networks of SR proteins are complex—they are regulated by the SR proteins themselves, they are phosphorylated and dephosphorylated through interactions with kinase, and they participate in signal transduction pathways, whereby signaling cascades can link the splicing machinery to the exterior environment. In a complex network, SR proteins are involved in plant growth and development, signal transduction, responses to abiotic and biotic stresses, and metabolism. Here, I review the current status of research on plant SR proteins, construct a model of SR proteins function, and ask many questions about SR proteins in plants.
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Affiliation(s)
- Xiaoli Jin
- Departmeng of Agronomy, College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China
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11
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Interactome of Arabidopsis Thaliana. PLANTS 2022; 11:plants11030350. [PMID: 35161331 PMCID: PMC8838453 DOI: 10.3390/plants11030350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 01/24/2023]
Abstract
More than 95,000 protein–protein interactions of Arabidopsis thaliana have been published and deposited in databases. This dataset was supplemented by approximately 900 additional interactions, which were identified in the literature from the years 2002–2021. These protein–protein interactions were used as the basis for a Cytoscape network and were supplemented with data on subcellular localization, gene ontologies, biochemical properties and co-expression. The resulting network has been exemplarily applied in unraveling the PPI-network of the plant vacuolar proton-translocating ATPase (V-ATPase), which was selected due to its central importance for the plant cell. In particular, it is involved in cellular pH homeostasis, providing proton motive force necessary for transport processes, trafficking of proteins and, thereby, cell wall synthesis. The data points to regulation taking place on multiple levels: (a) a phosphorylation-dependent regulation by 14-3-3 proteins and by kinases such as WNK8 and NDPK1a, (b) an energy-dependent regulation via HXK1 and the glucose receptor RGS1 and (c) a Ca2+-dependent regulation by SOS2 and IDQ6. The known importance of V-ATPase for cell wall synthesis is supported by its interactions with several proteins involved in cell wall synthesis. The resulting network was further analyzed for (experimental) biases and was found to be enriched in nuclear, cytosolic and plasma membrane proteins but depleted in extracellular and mitochondrial proteins, in comparison to the entity of protein-coding genes. Among the processes and functions, proteins involved in transcription were highly abundant in the network. Subnetworks were extracted for organelles, processes and protein families. The degree of representation of organelles and processes reveals limitations and advantages in the current knowledge of protein–protein interactions, which have been mainly caused by a high number of database entries being contributed by only a few publications with highly specific motivations and methodologies that favor, for instance, interactions in the cytosol and the nucleus.
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Duarte GT, Pandey PK, Vaid N, Alseekh S, Fernie AR, Nikoloski Z, Laitinen RAE. Plasticity of rosette size in response to nitrogen availability is controlled by an RCC1-family protein. PLANT, CELL & ENVIRONMENT 2021; 44:3398-3411. [PMID: 34228823 DOI: 10.1111/pce.14146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 05/12/2023]
Abstract
Nitrogen (N) is fundamental to plant growth, development and yield. Genes underlying N utilization and assimilation are well-characterized, but mechanisms underpinning plasticity of different phenotypes in response to N remain elusive. Here, using Arabidopsis thaliana accessions, we dissected the genetic architecture of plasticity in early and late rosette diameter, flowering time and yield, in response to three levels of N in the soil. Furthermore, we found that the plasticity in levels of primary metabolites were related with the plasticities of the studied traits. Genome-wide association analysis identified three significant associations for phenotypic plasticity, one for early rosette diameter and two for flowering time. We confirmed that the gene At1g19880, hereafter named as PLASTICITY OF ROSETTE TO NITROGEN 1 (PROTON1), encoding for a regulator of chromatin condensation 1 (RCC1) family protein, conferred plasticity of rosette diameter in response to N. Treatment of PROTON1 T-DNA line with salt implied that the reduced plasticity of early rosette diameter was not a general growth response to stress. We further showed that plasticities of growth and flowering-related traits differed between environmental cues, indicating decoupled genetic programs regulating these traits. Our findings provide a prospective to identify genes that stabilize performance under fluctuating environments.
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Affiliation(s)
- Gustavo Turqueto Duarte
- Molecular Mechanisms of Plant Adaptation - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Prashant K Pandey
- Molecular Mechanisms of Plant Adaptation - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- National Research Council Canada (NRC-CNRC), Aquatic and Crop Resource Development (ACRD), Saskatoon, Saskatchewan, Canada
| | - Neha Vaid
- Molecular Mechanisms of Plant Adaptation - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Saleh Alseekh
- Central Metabolism - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- Department of Plant Metabolomics, Center of Plant Systems Biology, Plovdiv, Bulgaria
| | - Alisdair R Fernie
- Central Metabolism - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- Department of Plant Metabolomics, Center of Plant Systems Biology, Plovdiv, Bulgaria
| | - Zoran Nikoloski
- Systems Biology and Mathematical Modeling - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- Department of Bioinformatics and Mathematical Modeling, Center of Plant Systems Biology, Plovdiv, Bulgaria
- Bioinformatics, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Roosa A E Laitinen
- Molecular Mechanisms of Plant Adaptation - group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
- Organismal and Evolutionary Research Programme, Faculty of Biological and Environmental Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
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13
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Characterization of Local and Systemic Impact of Whitefly ( Bemisia tabaci) Feeding and Whitefly-Transmitted Tomato Mottle Virus Infection on Tomato Leaves by Comprehensive Proteomics. Int J Mol Sci 2020; 21:ijms21197241. [PMID: 33008056 PMCID: PMC7583044 DOI: 10.3390/ijms21197241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/21/2020] [Accepted: 09/26/2020] [Indexed: 11/23/2022] Open
Abstract
Tomato mottle virus (ToMoV) is a single-stranded DNA (ssDNA) begomovirus transmitted to solanaceous crops by the whitefly species complex (Bemisia tabaci), causing stunted growth, leaf mottling, and reduced yield. Using a genetic repertoire of seven genes, ToMoV pathogenesis includes the manipulation of multiple plant biological processes to circumvent antiviral defenses. To further understand the effects of whitefly feeding and whitefly-transmitted ToMoV infection on tomato plants (Solanum lycopersicum ‘Florida Lanai’), we generated comprehensive protein profiles of leaves subjected to feeding by either viruliferous whiteflies harboring ToMoV, or non-viruliferous whiteflies, or a no-feeding control. The effects of whitefly feeding and ToMoV infection were measured both locally and systemically by sampling either a mature leaf directly from the site of clip-cage confined whitefly feeding, or from a newly formed leaf 10 days post feeding (dpf). At 3 dpf, tomato’s response to ToMoV included proteins associated with translation initiation and elongation as well as plasmodesmata dynamics. In contrast, systemic impacts of ToMoV on younger leaves 10 dpf were more pronounced and included a virus-specific change in plant proteins associated with mRNA maturation and export, RNA-dependent DNA methylation, and other antiviral plant processes. Our analysis supports previous findings and provides novel insight into tomato’s local and systemic response to whitefly feeding and ToMoV infection.
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Park HJ, You YN, Lee A, Jung H, Jo SH, Oh N, Kim HS, Lee HJ, Kim JK, Kim YS, Jung C, Cho HS. OsFKBP20-1b interacts with the splicing factor OsSR45 and participates in the environmental stress response at the post-transcriptional level in rice. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 102:992-1007. [PMID: 31925835 DOI: 10.1111/tpj.14682] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 11/28/2019] [Accepted: 12/20/2019] [Indexed: 06/10/2023]
Abstract
Sessile plants have evolved distinct mechanisms to respond and adapt to adverse environmental conditions through diverse mechanisms including RNA processing. While the role of RNA processing in the stress response is well understood for Arabidopsis thaliana, limited information is available for rice (Oryza sativa). Here, we show that OsFKBP20-1b, belonging to the immunophilin family, interacts with the splicing factor OsSR45 in both nuclear speckles and cytoplasmic foci, and plays an essential role in post-transcriptional regulation of abiotic stress response. The expression of OsFKBP20-1b was highly upregulated under various abiotic stresses. Moreover genetic analysis revealed that OsFKBP20-1b positively affected transcription and pre-mRNA splicing of stress-responsive genes under abiotic stress conditions. In osfkbp20-1b loss-of-function mutants, the expression of stress-responsive genes was downregulated, while that of their splicing variants was increased. Conversely, in plants overexpressing OsFKBP20-1b, the expression of the same stress-responsive genes was strikingly upregulated under abiotic stress. In vivo experiments demonstrated that OsFKBP20-1b directly maintains protein stability of OsSR45 splicing factor. Furthermore, we found that the plant-specific OsFKBP20-1b gene has uniquely evolved as a paralogue only in some Poaceae species. Together, our findings suggest that OsFKBP20-1b-mediated RNA processing contributes to stress adaptation in rice.
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Affiliation(s)
- Hyun J Park
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
| | - Young N You
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
| | - Areum Lee
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Korea
| | - Haemyeong Jung
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Korea
| | - Seung H Jo
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Korea
| | - Nuri Oh
- Crop Biotechnology Institute/GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Hyun-Soon Kim
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
| | - Hyo-Jun Lee
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
| | - Ju-Kon Kim
- Crop Biotechnology Institute/GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
- Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Youn S Kim
- Crop Biotechnology Institute/GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Choonkyun Jung
- Crop Biotechnology Institute/GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
- Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang, 25354, Republic of Korea
| | - Hye S Cho
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, Korea University of Science and Technology, Daejeon, 34113, Korea
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15
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Xu X, Wan W, Jiang G, Xi Y, Huang H, Cai J, Chang Y, Duan CG, Mangrauthia SK, Peng X, Zhu JK, Zhu G. Nucleocytoplasmic Trafficking of the Arabidopsis WD40 Repeat Protein XIW1 Regulates ABI5 Stability and Abscisic Acid Responses. MOLECULAR PLANT 2019; 12:1598-1611. [PMID: 31295628 DOI: 10.1016/j.molp.2019.07.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 06/08/2019] [Accepted: 07/01/2019] [Indexed: 05/24/2023]
Abstract
WD40 repeat-containing proteins (WD40 proteins) serve as versatile scaffolds for protein-protein interactions, modulating a variety of cellular processes such as plant stress and hormone responses. Here we report the identification of a WD40 protein, XIW1 (for XPO1-interacting WD40 protein 1), which positively regulates the abscisic acid (ABA) response in Arabidopsis. XIW1 is located in the cytoplasm and nucleus. We found that it interacts with the nuclear transport receptor XPO1 and is exported by XPO1 from the nucleus. Mutation of XIW1 reduces the induction of ABA-responsive genes and the accumulation of ABA Insensitive 5 (ABI5), causing mutant plants with ABA-insensitive phenotypes during seed germination and seedling growth, and decreased drought stress resistance. ABA treatment upregulates the expression of XIW1, and both ABA and abiotic stresses promote XIW1 accumulation in the nucleus, where it interacts with ABI5. Loss of XIW1 function results in rapid proteasomal degradation of ABI5. Taken together, these findings suggest that XIW1 is a nucleocytoplasmic shuttling protein and plays a positive role in ABA responses by interacting with and maintaining the stability of ABI5 in the nucleus.
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Affiliation(s)
- Xuezhong Xu
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Wang Wan
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Guobin Jiang
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Yue Xi
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Haijian Huang
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Jiajia Cai
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Yanan Chang
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 201602, China
| | - Cheng-Guo Duan
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 201602, China
| | | | - Xinxiang Peng
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai 201602, China; Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907, USA.
| | - Guohui Zhu
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, South China Agricultural University, Guangzhou 510642, China.
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16
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Highly ABA-Induced 1 (HAI1)-Interacting protein HIN1 and drought acclimation-enhanced splicing efficiency at intron retention sites. Proc Natl Acad Sci U S A 2019; 116:22376-22385. [PMID: 31611386 PMCID: PMC6825267 DOI: 10.1073/pnas.1906244116] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The Highly ABA-Induced 1 (HAI1) protein phosphatase is a central component of drought-related signaling. A screen for HAI1-interacting proteins identified HAI1-Interactor 1 (HIN1), a nuclear protein of unknown function which could be dephosphorylated by HAI1 in vitro. HIN1 colocalization and interaction with serine-arginine rich (SR) splicing factors and appearance of nuclear speckle-localized HIN1 during low water potential (ψw) stress suggested a pre-mRNA splicing-related function. RNA sequencing of Arabidopsis Col-0 wild type identified more than 500 introns where moderate severity low ψw altered intron retention (IR) frequency. Surprisingly, nearly 90% of these had increased splicing efficiency (decreased IR) during stress. For one-third of these introns, ectopic HIN1 expression (35S:HIN1) in unstressed plants mimicked the increased splicing efficiency seen in stress-treated wild type. HIN1 bound to a GAA-repeat, Exonic Splicing Enhancer-like RNA motif enriched in flanking sequence around HIN1-regulated introns. Genes with stress and HIN1-affected splicing efficiency were enriched for abiotic stress and signaling-related functions. The 35S:HIN1 plants had enhanced growth maintenance during low ψw, while hin1 mutants had reduced growth, further indicating the role of HIN1 in drought response. HIN1 is annotated as an MYB/SANT domain protein but has limited homology to other MYB/SANT proteins and is not related to known yeast or metazoan RNA-binding proteins or splicing regulators. Together these data identify HIN1 as a plant-specific RNA-binding protein, show a specific effect of drought acclimation to promote splicing efficiency of IR-prone introns, and also discover HAI1-HIN1 interaction and dephosphorylation that connects stress signaling to splicing regulation.
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17
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Li Y, Yang J, Shang X, Lv W, Xia C, Wang C, Feng J, Cao Y, He H, Li L, Ma L. SKIP regulates environmental fitness and floral transition by forming two distinct complexes in Arabidopsis. THE NEW PHYTOLOGIST 2019; 224:321-335. [PMID: 31209881 DOI: 10.1111/nph.15990] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 06/07/2019] [Indexed: 05/08/2023]
Abstract
Ski-interacting protein (SKIP) is a bifunctional regulator of gene expression that works as a splicing factor as part of the spliceosome and as a transcriptional activator by interacting with EARLY FLOWERING 7 (ELF7). MOS4-Associated Complex 3A (MAC3A) and MAC3B interact physically and genetically with SKIP, mediate the alternative splicing of c. 50% of the expressed genes in the Arabidopsis genome, and are required for the splicing of a similar set of genes to that of SKIP. SKIP interacts physically and genetically with splicing factors and Polymerase-Associated Factor 1 complex (Paf1c) components. However, these splicing factors do not interact either physically or genetically with Paf1c components. The SKIP-spliceosome complex mediates circadian clock function and abiotic stress responses by controlling the alternative splicing of pre-mRNAs encoded by clock- and stress tolerance-related genes. The SKIP-Paf1c complex regulates the floral transition by activating FLOWERING LOCUS C (FLC) transcription. Our data reveal that SKIP regulates floral transition and environmental fitness via its incorporation into two distinct complexes that regulate gene expression transcriptionally and post-transcriptionally, respectively. It will be interesting to discover in future studies whether SKIP is required for integration of environmental fitness and growth by control of the incorporation of SKIP into spliceosome or Paf1c in plants.
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Affiliation(s)
- Yan Li
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Jing Yang
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Xudong Shang
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Wenzhu Lv
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Congcong Xia
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Chen Wang
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Jinlin Feng
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Ying Cao
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Hang He
- College of Life Sciences, Peking University, Beijing, 100048, China
| | - Legong Li
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
| | - Ligeng Ma
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, Beijing, 100048, China
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18
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Chen SL, Rooney TJ, Hu AR, Beard HS, Garrett WM, Mangalath LM, Powers JJ, Cooper B, Zhang XN. Quantitative Proteomics Reveals a Role for SERINE/ARGININE-Rich 45 in Regulating RNA Metabolism and Modulating Transcriptional Suppression via the ASAP Complex in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2019; 10:1116. [PMID: 31608083 PMCID: PMC6761909 DOI: 10.3389/fpls.2019.01116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 08/14/2019] [Indexed: 05/12/2023]
Abstract
Pre-mRNA alternative splicing is a conserved mechanism for eukaryotic cells to leverage existing genetic resources to create a diverse pool of protein products. It is regulated in coordination with other events in RNA metabolism such as transcription, polyadenylation, RNA transport, and nonsense-mediated decay via protein networks. SERINE/ARGININE-RICH 45 (SR45) is thought to be a neutral splicing regulator. It is orthologous to a component of the apoptosis and splicing-associated protein (ASAP) complex functioning to regulate RNA metabolism at multiple levels. Within this context, we try to understand why the sr45-1 mutant Arabidopsis has malformed flowers, delayed flowering time, and increased disease resistance. Prior studies revealed increased expression for some disease resistance genes and the flowering suppressor Flowering Locus C (FLC) in sr45-1 mutants and a physical association between SR45 and reproductive process-related RNAs. Here, we used Tandem Mass Tag-based quantitative mass spectrometry to compare the protein abundance from inflorescence between Arabidopsis wild-type (Col-0) and sr45-1 mutant plants. A total of 7,206 proteins were quantified, of which 227 proteins exhibited significantly different accumulation. Only a small percentage of these proteins overlapped with the dataset of RNAs with altered expression. The proteomics results revealed that the sr45-1 mutant had increased amounts of enzymes for glucosinolate biosynthesis which are important for disease resistance. Furthermore, the mutant inflorescence had a drastically reduced amount of the Sin3-associated protein 18 (SAP18), a second ASAP complex component, despite no significant reduction in SAP18 RNA. The third ASAP component protein, ACINUS, also had lower abundance without significant RNA changes in the sr45-1 mutant. To test the effect of SR45 on SAP18, a SAP18-GFP fusion protein was overproduced in transgenic Arabidopsis Col-0 and sr45-1 plants. SAP18-GFP has less accumulation in the nucleus, the site of activity for the ASAP complex, without SR45. Furthermore, transgenic sr45-1 mutants overproducing SAP18-GFP expressed even more FLC and had a more severe flowering delay than non-transgenic sr45-1 mutants. These results suggest that SR45 is required to maintain the wild-type level of SAP18 protein accumulation in the nucleus and that FLC-regulated flowering time is regulated by the correct expression and localization of the ASAP complex.
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Affiliation(s)
- Samuel L. Chen
- Bioinformatics Program, St. Bonaventure University, St. Bonaventure, NY, United States
| | - Timothy J. Rooney
- Biochemistry Program, St. Bonaventure University, St. Bonaventure, NY, United States
| | - Anna R. Hu
- Biochemistry Program, St. Bonaventure University, St. Bonaventure, NY, United States
| | - Hunter S. Beard
- Soybean Genomics and Improvement Laboratory, USDA-ARS, Beltsville, MD, United States
| | - Wesley M. Garrett
- Animal Biosciences & Biotechnology Laboratory, USDA-ARS, Beltsville, MD, United States
| | - Leann M. Mangalath
- Department of Biology, St. Bonaventure University, St. Bonaventure, NY, United States
| | - Jordan J. Powers
- Biochemistry Program, St. Bonaventure University, St. Bonaventure, NY, United States
| | - Bret Cooper
- Soybean Genomics and Improvement Laboratory, USDA-ARS, Beltsville, MD, United States
| | - Xiao-Ning Zhang
- Biochemistry Program, St. Bonaventure University, St. Bonaventure, NY, United States
- Department of Biology, St. Bonaventure University, St. Bonaventure, NY, United States
- *Correspondence: Xiao-Ning Zhang,
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Park YJ, Lee JH, Kim JY, Park CM. Alternative RNA Splicing Expands the Developmental Plasticity of Flowering Transition. FRONTIERS IN PLANT SCIENCE 2019; 10:606. [PMID: 31134122 PMCID: PMC6517538 DOI: 10.3389/fpls.2019.00606] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 04/25/2019] [Indexed: 05/03/2023]
Abstract
Precise control of the developmental phase transitions, which ranges from seed germination to flowering induction and senescence, is essential for propagation and reproductive success in plants. Flowering induction represents the vegetative-to-reproductive phase transition. An extensive array of genes controlling the flowering transition has been identified, and signaling pathways that incorporate endogenous and environmental cues into the developmental phase transition have been explored in various plant species. Notably, recent accumulating evidence indicate that multiple transcripts are often produced from many of the flowering time genes via alternative RNA splicing, which is known to diversify the transcriptomes and proteasomes in eukaryotes. It is particularly interesting that some alternatively spliced protein isoforms, including COβ and FT2β, function differentially from or even act as competitive inhibitors of the corresponding functional proteins by forming non-functional heterodimers. The alternative splicing events of the flowering time genes are modulated by developmental and environmental signals. It is thus necessary to elucidate molecular schemes controlling alternative splicing and functional characterization of splice protein variants for understanding how genetic diversity and developmental plasticity of the flowering transition are achieved in optimizing the time of flowering under changing climates. In this review, we present current knowledge on the alternative splicing-driven control of flowering time. In addition, we discuss physiological and biochemical importance of the alternative splicing events that occur during the flowering transition as a molecular means of enhancing plant adaptation capabilities.
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Affiliation(s)
- Young-Joon Park
- Department of Chemistry, Seoul National University, Seoul, South Korea
| | - June-Hee Lee
- Department of Chemistry, Seoul National University, Seoul, South Korea
| | - Jae Young Kim
- Department of Chemistry, Seoul National University, Seoul, South Korea
| | - Chung-Mo Park
- Department of Chemistry, Seoul National University, Seoul, South Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, South Korea
- *Correspondence: Chung-Mo Park,
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20
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Liu GT, Jiang JF, Liu XN, Jiang JZ, Sun L, Duan W, Li RM, Wang Y, Lecourieux D, Liu CH, Li SH, Wang LJ. New insights into the heat responses of grape leaves via combined phosphoproteomic and acetylproteomic analyses. HORTICULTURE RESEARCH 2019; 6:100. [PMID: 31666961 PMCID: PMC6804945 DOI: 10.1038/s41438-019-0183-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 05/04/2023]
Abstract
Heat stress is a serious and widespread threat to the quality and yield of many crop species, including grape (Vitis vinifera L.), which is cultivated worldwide. Here, we conducted phosphoproteomic and acetylproteomic analyses of leaves of grape plants cultivated under four distinct temperature regimes. The phosphorylation or acetylation of a total of 1011 phosphoproteins with 1828 phosphosites and 96 acetyl proteins with 148 acetyl sites changed when plants were grown at 35 °C, 40 °C, and 45 °C in comparison with the proteome profiles of plants grown at 25 °C. The greatest number of changes was observed at the relatively high temperatures. Functional classification and enrichment analysis indicated that phosphorylation, rather than acetylation, of serine/arginine-rich splicing factors was involved in the response to high temperatures. This finding is congruent with previous observations by which alternative splicing events occurred more frequently in grapevine under high temperature. Changes in acetylation patterns were more common than changes in phosphorylation patterns in photosynthesis-related proteins at high temperatures, while heat-shock proteins were associated more with modifications involving phosphorylation than with those involving acetylation. Nineteen proteins were identified with changes associated with both phosphorylation and acetylation, which is consistent with crosstalk between these posttranslational modification types.
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Affiliation(s)
- Guo-Tian Liu
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
- College of Horticulture, Northwest A&F University, Yangling, 712100 China
- University of Chinese Academy of Sciences, Beijing, 100093 China
| | - Jian-Fu Jiang
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009 China
| | - Xin-Na Liu
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100093 China
| | - Jin-Zhu Jiang
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100093 China
| | - Lei Sun
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009 China
| | - Wei Duan
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
| | - Rui-Min Li
- College of Horticulture, Northwest A&F University, Yangling, 712100 China
| | - Yi Wang
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100093 China
| | - David Lecourieux
- Universite´ de Bordeaux, ISVV, Ecophysiologie et Ge´nomique Fonctionnelle de la Vigne, UMR 1287, F-33140 Villenave d’Ornon, France
- INRA, ISVV, Ecophysiologie et Ge´nomique Fonctionnelle de la Vigne, UMR 1287, F-33140 Villenave d’Ornon, France
| | - Chong-Huai Liu
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009 China
| | - Shao-Hua Li
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100093 China
| | - Li-Jun Wang
- Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093 China
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21
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Laloum T, Martín G, Duque P. Alternative Splicing Control of Abiotic Stress Responses. TRENDS IN PLANT SCIENCE 2018; 23:140-150. [PMID: 29074233 DOI: 10.1016/j.tplants.2017.09.019] [Citation(s) in RCA: 281] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 09/25/2017] [Accepted: 09/26/2017] [Indexed: 05/20/2023]
Abstract
Alternative splicing, which generates multiple transcripts from the same gene, is an important modulator of gene expression that can increase proteome diversity and regulate mRNA levels. In plants, this post-transcriptional mechanism is markedly induced in response to environmental stress, and recent studies have identified alternative splicing events that allow rapid adjustment of the abundance and function of key stress-response components. In agreement, plant mutants defective in splicing factors are severely impaired in their response to abiotic stress. Notably, mounting evidence indicates that alternative splicing regulates stress responses largely by targeting the abscisic acid (ABA) pathway. We review here current understanding of post-transcriptional control of plant stress tolerance via alternative splicing and discuss research challenges for the near future.
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Affiliation(s)
- Tom Laloum
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | - Guiomar Martín
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | - Paula Duque
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal.
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22
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Zhang XN, Shi Y, Powers JJ, Gowda NB, Zhang C, Ibrahim HMM, Ball HB, Chen SL, Lu H, Mount SM. Transcriptome analyses reveal SR45 to be a neutral splicing regulator and a suppressor of innate immunity in Arabidopsis thaliana. BMC Genomics 2017; 18:772. [PMID: 29020934 PMCID: PMC5637254 DOI: 10.1186/s12864-017-4183-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/05/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Regulation of pre-mRNA splicing diversifies protein products and affects many biological processes. Arabidopsis thaliana Serine/Arginine-rich 45 (SR45), regulates pre-mRNA splicing by interacting with other regulatory proteins and spliceosomal subunits. Although SR45 has orthologs in diverse eukaryotes, including human RNPS1, the sr45-1 null mutant is viable. Narrow flower petals and reduced seed formation suggest that SR45 regulates genes involved in diverse processes, including reproduction. To understand how SR45 is involved in the regulation of reproductive processes, we studied mRNA from the wild-type and sr45-1 inflorescences using RNA-seq, and identified SR45-bound RNAs by immunoprecipitation. RESULTS Using a variety of bioinformatics tools, we identified a total of 358 SR45 differentially regulated (SDR) genes, 542 SR45-dependent alternative splicing (SAS) events, and 1812 SR45-associated RNAs (SARs). There is little overlap between SDR genes and SAS genes, and neither set of genes is enriched for flower or seed development. However, transcripts from reproductive process genes are significantly overrepresented in SARs. In exploring the fate of SARs, we found that a total of 81 SARs are subject to alternative splicing, while 14 of them are known Nonsense-Mediated Decay (NMD) targets. Motifs related to GGNGG are enriched both in SARs and near different types of SAS events, suggesting that SR45 recognizes this motif directly. Genes involved in plant defense are significantly over-represented among genes whose expression is suppressed by SR45, and sr45-1 plants do indeed show enhanced immunity. CONCLUSION We find that SR45 is a suppressor of innate immunity. We find that a single motif (GGNGG) is highly enriched in both RNAs bound by SR45 and in sequences near SR45- dependent alternative splicing events in inflorescence tissue. We find that the alternative splicing events regulated by SR45 are enriched for this motif whether the effect of SR45 is activation or repression of the particular event. Thus, our data suggests that SR45 acts to control splice site choice in a way that defies simple categorization as an activator or repressor of splicing.
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Affiliation(s)
- Xiao-Ning Zhang
- Biochemistry Program, Department of Biology, St. Bonaventure University, St. Bonaventure, NY, 14778, USA. .,CMNS-Institute for Advanced Computer Studies, University of Maryland, College Park, MD, 20742, USA.
| | - Yifei Shi
- Department of Cell Biology and Molecular Genetics and Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, 20742, USA
| | - Jordan J Powers
- Biochemistry Program, St. Bonaventure University, St. Bonaventure, NY, 14778, USA
| | - Nikhil B Gowda
- Department of Biology, St. Bonaventure University, St. Bonaventure, NY, 14778, USA
| | - Chong Zhang
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD, 21250, USA
| | - Heba M M Ibrahim
- Department of Cell Biology and Molecular Genetics and Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, 20742, USA.,Genetics Department, Faculty of Agriculture, Cairo University, Cairo, Egypt
| | - Hannah B Ball
- Biochemistry Program, St. Bonaventure University, St. Bonaventure, NY, 14778, USA
| | - Samuel L Chen
- Bioinformatics Program, St. Bonaventure University, St. Bonaventure, NY, 14778, USA
| | - Hua Lu
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD, 21250, USA
| | - Stephen M Mount
- Department of Cell Biology and Molecular Genetics and Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, 20742, USA
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23
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Alternative Splicing in Plant Genes: A Means of Regulating the Environmental Fitness of Plants. Int J Mol Sci 2017; 18:ijms18020432. [PMID: 28230724 PMCID: PMC5343966 DOI: 10.3390/ijms18020432] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 02/04/2017] [Accepted: 02/10/2017] [Indexed: 01/01/2023] Open
Abstract
Gene expression can be regulated through transcriptional and post-transcriptional mechanisms. Transcription in eukaryotes produces pre-mRNA molecules, which are processed and spliced post-transcriptionally to create translatable mRNAs. More than one mRNA may be produced from a single pre-mRNA by alternative splicing (AS); thus, AS serves to diversify an organism’s transcriptome and proteome. Previous studies of gene expression in plants have focused on the role of transcriptional regulation in response to environmental changes. However, recent data suggest that post-transcriptional regulation, especially AS, is necessary for plants to adapt to a changing environment. In this review, we summarize recent advances in our understanding of AS during plant development in response to environmental changes. We suggest that alternative gene splicing is a novel means of regulating the environmental fitness of plants.
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Carvalho RF, Szakonyi D, Simpson CG, Barbosa ICR, Brown JWS, Baena-González E, Duque P. The Arabidopsis SR45 Splicing Factor, a Negative Regulator of Sugar Signaling, Modulates SNF1-Related Protein Kinase 1 Stability. THE PLANT CELL 2016; 28:1910-25. [PMID: 27436712 PMCID: PMC5006706 DOI: 10.1105/tpc.16.00301] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 07/05/2016] [Accepted: 07/19/2016] [Indexed: 05/19/2023]
Abstract
The ability to sense and respond to sugar signals allows plants to cope with environmental and metabolic changes by adjusting growth and development accordingly. We previously reported that the SR45 splicing factor negatively regulates glucose signaling during early seedling development in Arabidopsis thaliana Here, we show that under glucose-fed conditions, the Arabidopsis sr45-1 loss-of-function mutant contains higher amounts of the energy-sensing SNF1-Related Protein Kinase 1 (SnRK1) despite unaffected SnRK1 transcript levels. In agreement, marker genes for SnRK1 activity are upregulated in sr45-1 plants, and the glucose hypersensitivity of sr45-1 is attenuated by disruption of the SnRK1 gene. Using a high-resolution RT-PCR panel, we found that the sr45-1 mutation broadly targets alternative splicing in vivo, including that of the SR45 pre-mRNA itself. Importantly, the enhanced SnRK1 levels in sr45-1 are suppressed by a proteasome inhibitor, indicating that SR45 promotes targeting of the SnRK1 protein for proteasomal destruction. Finally, we demonstrate that SR45 regulates alternative splicing of the Arabidopsis 5PTase13 gene, which encodes an inositol polyphosphate 5-phosphatase previously shown to interact with and regulate the stability of SnRK1 in vitro, thus providing a mechanistic link between SR45 function and the modulation of degradation of the SnRK1 energy sensor in response to sugars.
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Affiliation(s)
| | - Dóra Szakonyi
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | - Craig G Simpson
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, United Kingdom
| | | | - John W S Brown
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, United Kingdom University of Dundee at The James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, United Kingdom
| | | | - Paula Duque
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
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