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Kafri M, Patena W, Martin L, Wang L, Gomer G, Ergun SL, Sirkejyan AK, Goh A, Wilson AT, Gavrilenko SE, Breker M, Roichman A, McWhite CD, Rabinowitz JD, Cross FR, Wühr M, Jonikas MC. Systematic identification and characterization of genes in the regulation and biogenesis of photosynthetic machinery. Cell 2023; 186:5638-5655.e25. [PMID: 38065083 PMCID: PMC10760936 DOI: 10.1016/j.cell.2023.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 08/03/2023] [Accepted: 11/03/2023] [Indexed: 12/18/2023]
Abstract
Photosynthesis is central to food production and the Earth's biogeochemistry, yet the molecular basis for its regulation remains poorly understood. Here, using high-throughput genetics in the model eukaryotic alga Chlamydomonas reinhardtii, we identify with high confidence (false discovery rate [FDR] < 0.11) 70 poorly characterized genes required for photosynthesis. We then enable the functional characterization of these genes by providing a resource of proteomes of mutant strains, each lacking one of these genes. The data allow assignment of 34 genes to the biogenesis or regulation of one or more specific photosynthetic complexes. Further analysis uncovers biogenesis/regulatory roles for at least seven proteins, including five photosystem I mRNA maturation factors, the chloroplast translation factor MTF1, and the master regulator PMR1, which regulates chloroplast genes via nuclear-expressed factors. Our work provides a rich resource identifying regulatory and functional genes and placing them into pathways, thereby opening the door to a system-level understanding of photosynthesis.
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Affiliation(s)
- Moshe Kafri
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Weronika Patena
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Lance Martin
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics and Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Lianyong Wang
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Gillian Gomer
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Sabrina L Ergun
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Howard Hughes Medical Institute, Princeton University, Princeton, NJ 08544, USA
| | - Arthur K Sirkejyan
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Audrey Goh
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Alexandra T Wilson
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Sophia E Gavrilenko
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Michal Breker
- Laboratory of Cell Cycle Genetics, The Rockefeller University, New York, NY 10021, USA
| | - Asael Roichman
- Lewis-Sigler Institute for Integrative Genomics and Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Claire D McWhite
- Lewis-Sigler Institute for Integrative Genomics and Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Joshua D Rabinowitz
- Lewis-Sigler Institute for Integrative Genomics and Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Frederick R Cross
- Laboratory of Cell Cycle Genetics, The Rockefeller University, New York, NY 10021, USA
| | - Martin Wühr
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics and Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Martin C Jonikas
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Howard Hughes Medical Institute, Princeton University, Princeton, NJ 08544, USA.
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2
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Ma K, Deng L, Wu H, Fan J. Towards green biomanufacturing of high-value recombinant proteins using promising cell factory: Chlamydomonas reinhardtii chloroplast. BIORESOUR BIOPROCESS 2022; 9:83. [PMID: 38647750 PMCID: PMC10992328 DOI: 10.1186/s40643-022-00568-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 07/29/2022] [Indexed: 11/10/2022] Open
Abstract
Microalgae are cosmopolitan organisms in nature with short life cycles, playing a tremendous role in reducing the pressure of industrial carbon emissions. Besides, microalgae have the unique advantages of being photoautotrophic and harboring both prokaryotic and eukaryotic expression systems, becoming a popular host for recombinant proteins. Currently, numerous advanced molecular tools related to microalgal transgenesis have been explored and established, especially for the model species Chlamydomonas reinhardtii (C. reinhardtii hereafter). The development of genetic tools and the emergence of new strategies further increase the feasibility of developing C. reinhardtii chloroplasts as green factories, and the strong genetic operability of C. reinhardtii endows it with enormous potential as a synthetic biology platform. At present, C. reinhardtii chloroplasts could successfully produce plenty of recombinant proteins, including antigens, antibodies, antimicrobial peptides, protein hormones and enzymes. However, additional techniques and toolkits for chloroplasts need to be developed to achieve efficient and markerless editing of plastid genomes. Mining novel genetic elements and selectable markers will be more intensively studied in the future, and more factors affecting protein expression are urged to be explored. This review focuses on the latest technological progress of selectable markers for Chlamydomonas chloroplast genetic engineering and the factors that affect the efficiency of chloroplast protein expression. Furthermore, urgent challenges and prospects for future development are pointed out.
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Affiliation(s)
- Ke Ma
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China
| | - Lei Deng
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China
| | - Haizhen Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
- Department of Applied Biology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
| | - Jianhua Fan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
- Department of Applied Biology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, 832003, People's Republic of China.
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3
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Kück U, Schmitt O. The Chloroplast Trans-Splicing RNA-Protein Supercomplex from the Green Alga Chlamydomonas reinhardtii. Cells 2021; 10:cells10020290. [PMID: 33535503 PMCID: PMC7912774 DOI: 10.3390/cells10020290] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 12/27/2022] Open
Abstract
In eukaryotes, RNA trans-splicing is a significant RNA modification process for the end-to-end ligation of exons from separately transcribed primary transcripts to generate mature mRNA. So far, three different categories of RNA trans-splicing have been found in organisms within a diverse range. Here, we review trans-splicing of discontinuous group II introns, which occurs in chloroplasts and mitochondria of lower eukaryotes and plants. We discuss the origin of intronic sequences and the evolutionary relationship between chloroplast ribonucleoprotein complexes and the nuclear spliceosome. Finally, we focus on the ribonucleoprotein supercomplex involved in trans-splicing of chloroplast group II introns from the green alga Chlamydomonas reinhardtii. This complex has been well characterized genetically and biochemically, resulting in a detailed picture of the chloroplast ribonucleoprotein supercomplex. This information contributes substantially to our understanding of the function of RNA-processing machineries and might provide a blueprint for other splicing complexes involved in trans- as well as cis-splicing of organellar intron RNAs.
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Dai D, Ma Z, Song R. Maize kernel development. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2021; 41:2. [PMID: 37309525 PMCID: PMC10231577 DOI: 10.1007/s11032-020-01195-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/03/2020] [Indexed: 06/14/2023]
Abstract
Maize (Zea mays) is a leading cereal crop in the world. The maize kernel is the storage organ and the harvest portion of this crop and is closely related to its yield and quality. The development of maize kernel is initiated by the double fertilization event, leading to the formation of a diploid embryo and a triploid endosperm. The embryo and endosperm are then undergone independent developmental programs, resulting in a mature maize kernel which is comprised of a persistent endosperm, a large embryo, and a maternal pericarp. Due to the well-characterized morphogenesis and powerful genetics, maize kernel has long been an excellent model for the study of cereal kernel development. In recent years, with the release of the maize reference genome and the development of new genomic technologies, there has been an explosive expansion of new knowledge for maize kernel development. In this review, we overviewed recent progress in the study of maize kernel development, with an emphasis on genetic mapping of kernel traits, transcriptome analysis during kernel development, functional gene cloning of kernel mutants, and genetic engineering of kernel traits.
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Affiliation(s)
- Dawei Dai
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193 China
- Shanghai Key Laboratory of Bio-Energy Crops, Plant Science Center, School of Life Sciences, Shanghai University, Shanghai, 200444 China
| | - Zeyang Ma
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193 China
| | - Rentao Song
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193 China
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5
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Macedo-Osorio KS, Martínez-Antonio A, Badillo-Corona JA. Pas de Trois: An Overview of Penta-, Tetra-, and Octo-Tricopeptide Repeat Proteins From Chlamydomonas reinhardtii and Their Role in Chloroplast Gene Expression. FRONTIERS IN PLANT SCIENCE 2021; 12:775366. [PMID: 34868174 PMCID: PMC8635915 DOI: 10.3389/fpls.2021.775366] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/26/2021] [Indexed: 05/05/2023]
Abstract
Penta-, Tetra-, and Octo-tricopeptide repeat (PPR, TPR, and OPR) proteins are nucleus-encoded proteins composed of tandem repeats of 35, 34, and 38-40 amino acids, respectively. They form helix-turn-helix structures that interact with mRNA or other proteins and participate in RNA stabilization, processing, maturation, and act as translation enhancers of chloroplast and mitochondrial mRNAs. These helical repeat proteins are unevenly present in plants and algae. While PPR proteins are more abundant in plants than in algae, OPR proteins are more abundant in algae. In Arabidopsis, maize, and rice there have been 450, 661, and 477 PPR proteins identified, respectively, which contrasts with only 14 PPR proteins identified in Chlamydomonas reinhardtii. Likewise, more than 120 OPR proteins members have been predicted from the nuclear genome of C. reinhardtii and only one has been identified in Arabidopsis thaliana. Due to their abundance in land plants, PPR proteins have been largely characterized making it possible to elucidate their RNA-binding code. This has even allowed researchers to generate engineered PPR proteins with defined affinity to a particular target, which has served as the basis to develop tools for gene expression in biotechnological applications. However, fine elucidation of the helical repeat proteins code in Chlamydomonas is a pending task. In this review, we summarize the current knowledge on the role PPR, TPR, and OPR proteins play in chloroplast gene expression in the green algae C. reinhardtii, pointing to relevant similarities and differences with their counterparts in plants. We also recapitulate on how these proteins have been engineered and shown to serve as mRNA regulatory factors for biotechnological applications in plants and how this could be used as a starting point for applications in algae.
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Affiliation(s)
- Karla S. Macedo-Osorio
- Instituto Politécnico Nacional, Unidad Profesional Interdisciplinaria de Biotecnología, México City, México
- Biological Engineering Laboratory, Genetic Engineering Department, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional-Unidad Irapuato, Irapuato, México
- División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Xochimilco, México City, México
- *Correspondence: Karla S. Macedo-Osorio,
| | - Agustino Martínez-Antonio
- Biological Engineering Laboratory, Genetic Engineering Department, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional-Unidad Irapuato, Irapuato, México
| | - Jesús A. Badillo-Corona
- Instituto Politécnico Nacional, Unidad Profesional Interdisciplinaria de Biotecnología, México City, México
- Jesús A. Badillo-Corona,
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6
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Ozawa SI, Cavaiuolo M, Jarrige D, Kuras R, Rutgers M, Eberhard S, Drapier D, Wollman FA, Choquet Y. The OPR Protein MTHI1 Controls the Expression of Two Different Subunits of ATP Synthase CFo in Chlamydomonas reinhardtii. THE PLANT CELL 2020; 32:1179-1203. [PMID: 31988263 PMCID: PMC7145495 DOI: 10.1105/tpc.19.00770] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 01/02/2020] [Accepted: 01/27/2020] [Indexed: 05/19/2023]
Abstract
In the green alga Chlamydomonas (Chlamydomonas r einhardtii), chloroplast gene expression is tightly regulated posttranscriptionally by gene-specific trans-acting protein factors. Here, we report the identification of the octotricopeptide repeat protein MTHI1, which is critical for the biogenesis of chloroplast ATP synthase oligomycin-sensitive chloroplast coupling factor. Unlike most trans-acting factors characterized so far in Chlamydomonas, which control the expression of a single gene, MTHI1 targets two distinct transcripts: it is required for the accumulation and translation of atpH mRNA, encoding a subunit of the selective proton channel, but it also enhances the translation of atpI mRNA, which encodes the other subunit of the channel. MTHI1 targets the 5' untranslated regions of both the atpH and atpI genes. Coimmunoprecipitation and small RNA sequencing revealed that MTHI1 binds specifically a sequence highly conserved among Chlorophyceae and the Ulvale clade of Ulvophyceae at the 5' end of triphosphorylated atpH mRNA. A very similar sequence, located ∼60 nucleotides upstream of the atpI initiation codon, was also found in some Chlorophyceae and Ulvale algae species and is essential for atpI mRNA translation in Chlamydomonas. Such a dual-targeted trans-acting factor provides a means to coregulate the expression of the two proton hemi-channels.
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Affiliation(s)
- Shin-Ichiro Ozawa
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Marina Cavaiuolo
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Domitille Jarrige
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Richard Kuras
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Mark Rutgers
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Stephan Eberhard
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Dominique Drapier
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Francis-André Wollman
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Yves Choquet
- Unité Mixte de Recherche 7141, Centre National de la Recherche Scientifique and Sorbonne Université, Institut de Biologie Physico-Chimique, F-75005 Paris, France
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7
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Wang HC, Chen Z, Yang YZ, Sun F, Ding S, Li XL, Xu C, Tan BC. PPR14 Interacts With PPR-SMR1 and CRM Protein Zm-mCSF1 to Facilitate Mitochondrial Intron Splicing in Maize. FRONTIERS IN PLANT SCIENCE 2020; 11:814. [PMID: 32595685 PMCID: PMC7304344 DOI: 10.3389/fpls.2020.00814] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 05/20/2020] [Indexed: 05/17/2023]
Abstract
In plants, splicing of organellar group II introns involves numerous nucleus-encoded trans-factors. But, how these trans-factors function and interact is not well understood. Here we report the function of a pentatricopeptide repeat (PPR) protein PPR14 and its physical relationship with other splicing factors in mitochondria. Null mutations of PPR14 severely arrest the embryo and endosperm development, causing an empty pericarp phenotype. PPR14 is required for the splicing of NADH dehydrogenase 2 (nad2) intron 3 and nad7 introns 1 and 2 in mitochondria. The absence of nad2 and nad7 transcripts leads to disruption of the mitochondrial complex I assembly and abolishes its NADH dehydrogenase activity. This is accompanied with increased levels of other mitochondrial complexes and elevated expression of the alternative oxidase proteins. As the function of PPR14 overlaps with PPR-SMR1 and the CRM-domain containing protein Zm-mCSF1, we tested their interactions. Protein-protein interaction analysis indicated that PPR14 interacts with PPR-SMR1 and Zm-mCSF1, suggesting that these three proteins may form a complex. As PPR proteins and CRM-domain containing proteins have many members in mitochondria and chloroplasts, we propose that organellar group II intron splicing is probably mediated by a dynamic complex that includes different PPR and CRM proteins in plants.
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8
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Chen Z, Wang HC, Shen J, Sun F, Wang M, Xu C, Tan BC. PPR-SMR1 is required for the splicing of multiple mitochondrial introns, interacts with Zm-mCSF1, and is essential for seed development in maize. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:5245-5258. [PMID: 31257441 PMCID: PMC6793435 DOI: 10.1093/jxb/erz305] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/19/2019] [Indexed: 05/18/2023]
Abstract
Group II introns are ribozymes that can excise themselves from precursor-RNA transcripts, but plant organellar group II introns have structural deviations that inhibit ribozyme activity. Therefore, splicing of these introns requires the assistance of nuclear- and/or organellar-encoded splicing factors; however, how these splicing factors function remains unclear. In this study, we report the functions and interactions of two splicing factors, PPR-SMR1 and Zm-mCSF1, in intron splicing in maize mitochondria. PPR-SMR1 is a SMR domain-containing pentatricopeptide repeat (PPR) protein and Zm-mCSF1 is a CRM domain-containing protein, and both are targeted to mitochondria. Loss-of-function mutations in each of them severely arrests embryogenesis and endosperm development in maize. Functional analyses indicate that PPR-SMR1 and Zm-mCSF1 are required for the splicing of most mitochondrial group II introns. Among them, nad2-intron 2 and 3, and nad5-intron 1 are PPR-SMR1/Zm-mCSF1-dependent introns. Protein interaction assays suggest that PPR-SMR1 can interact with Zm-mCSF1 through its N-terminus, and that Zm-mCSF1 is self-interacting. Our findings suggest that PPR-SMR1, a novel splicing factor, acts in the splicing of multiple group II introns in maize mitochondria, and the protein-protein interaction between it and Zm-mCSF1 might allow the formation of large macromolecular splicing complexes.
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Affiliation(s)
- Zongliang Chen
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - Hong-Chun Wang
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - Jiayu Shen
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - Feng Sun
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - Miaodi Wang
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - Chunhui Xu
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - Bao-Cai Tan
- Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
- Correspondence:
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9
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Barua P, Lande NV, Subba P, Gayen D, Pinto S, Keshava Prasad TS, Chakraborty S, Chakraborty N. Dehydration-responsive nuclear proteome landscape of chickpea (Cicer arietinum L.) reveals phosphorylation-mediated regulation of stress response. PLANT, CELL & ENVIRONMENT 2019; 42:230-244. [PMID: 29749054 DOI: 10.1111/pce.13334] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 04/27/2018] [Accepted: 04/30/2018] [Indexed: 06/08/2023]
Abstract
Nonavailability of water or dehydration remains recurring climatic disorder affecting yield of major food crops, legumes in particular. Nuclear proteins (NPs) and phosphoproteins (NPPs) execute crucial cellular functions that form the regulatory hub for coordinated stress response. Phosphoproteins hold enormous influence over cellular signalling. Four-week-old seedlings of a grain legume, chickpea, were subjected to gradual dehydration, and NPs were extracted from unstressed control and from 72- and 144-hr stressed tissues. We identified 4,832 NPs and 478 phosphosites, corresponding to 299 unique NPPs involved in multivariate cellular processes including protein modification and gene expression regulation, among others. The identified proteins included several novel kinases, phosphatases, and transcription factors, besides 660 uncharacterized proteins. Spliceosome complex and splicing related proteins were dominant among differentially regulated NPPs, indicating their dehydration modulated regulation. Phospho-motif analysis revealed stress-induced enrichment of proline-directed serine phosphorylation. Association mapping of NPPs revealed predominance of differential phosphorylation of spliceosome and splicing associated proteins. Also, regulatory proteins of key processes viz., protein degradation, regulation of flowering time, and circadian clock were observed to undergo dehydration-induced dephosphorylation. The characterization of novel regulatory proteins would provide new insights into stress adaptation and enable directed genetic manipulations for developing climate-resilient crops.
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Affiliation(s)
- Pragya Barua
- National Institute of Plant Genome Research, Jawaharlal Nehru University Campus, Aruna, Asaf Ali Marg, New Delhi, 110067, India
| | - Nilesh Vikram Lande
- National Institute of Plant Genome Research, Jawaharlal Nehru University Campus, Aruna, Asaf Ali Marg, New Delhi, 110067, India
| | - Pratigya Subba
- YU-IOB Center for Systems Biology and Molecular Medicine, Yenepoya University, Mangalore, 575 018, India
| | - Dipak Gayen
- National Institute of Plant Genome Research, Jawaharlal Nehru University Campus, Aruna, Asaf Ali Marg, New Delhi, 110067, India
| | - Sneha Pinto
- YU-IOB Center for Systems Biology and Molecular Medicine, Yenepoya University, Mangalore, 575 018, India
| | - T S Keshava Prasad
- YU-IOB Center for Systems Biology and Molecular Medicine, Yenepoya University, Mangalore, 575 018, India
- International Technology Park, Institute of Bioinformatics, Bengaluru, 560066, India
| | - Subhra Chakraborty
- National Institute of Plant Genome Research, Jawaharlal Nehru University Campus, Aruna, Asaf Ali Marg, New Delhi, 110067, India
| | - Niranjan Chakraborty
- National Institute of Plant Genome Research, Jawaharlal Nehru University Campus, Aruna, Asaf Ali Marg, New Delhi, 110067, India
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10
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Vosseberg J, Snel B. Domestication of self-splicing introns during eukaryogenesis: the rise of the complex spliceosomal machinery. Biol Direct 2017; 12:30. [PMID: 29191215 PMCID: PMC5709842 DOI: 10.1186/s13062-017-0201-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/20/2017] [Indexed: 12/31/2022] Open
Abstract
ᅟ The spliceosome is a eukaryote-specific complex that is essential for the removal of introns from pre-mRNA. It consists of five small nuclear RNAs (snRNAs) and over a hundred proteins, making it one of the most complex molecular machineries. Most of this complexity has emerged during eukaryogenesis, a period that is characterised by a drastic increase in cellular and genomic complexity. Although not fully resolved, recent findings have started to shed some light on how and why the spliceosome originated. In this paper we review how the spliceosome has evolved and discuss its origin and subsequent evolution in light of different general hypotheses on the evolution of complexity. Comparative analyses have established that the catalytic core of this ribonucleoprotein (RNP) complex, as well as the spliceosomal introns, evolved from self-splicing group II introns. Most snRNAs evolved from intron fragments and the essential Prp8 protein originated from the protein that is encoded by group II introns. Proteins that functioned in other RNA processes were added to this core and extensive duplications of these proteins substantially increased the complexity of the spliceosome prior to the eukaryotic diversification. The splicing machinery became even more complex in animals and plants, yet was simplified in eukaryotes with streamlined genomes. Apparently, the spliceosome did not evolve its complexity gradually, but in rapid bursts, followed by stagnation or even simplification. We argue that although both adaptive and neutral evolution have been involved in the evolution of the spliceosome, especially the latter was responsible for the emergence of an enormously complex eukaryotic splicing machinery from simple self-splicing sequences. Reviewers This article was reviewed by W. Ford Doolittle, Eugene V. Koonin and Vivek Anantharaman.
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Affiliation(s)
- Julian Vosseberg
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Padualaan 8, 3584, CH, Utrecht, The Netherlands.
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Padualaan 8, 3584, CH, Utrecht, The Netherlands
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11
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Cavaiuolo M, Kuras R, Wollman F, Choquet Y, Vallon O. Small RNA profiling in Chlamydomonas: insights into chloroplast RNA metabolism. Nucleic Acids Res 2017; 45:10783-10799. [PMID: 28985404 PMCID: PMC5737564 DOI: 10.1093/nar/gkx668] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Revised: 07/18/2017] [Accepted: 07/28/2017] [Indexed: 12/20/2022] Open
Abstract
In Chlamydomonas reinhardtii, regulation of chloroplast gene expression is mainly post-transcriptional. It requires nucleus-encoded trans-acting protein factors for maturation/stabilization (M factors) or translation (T factors) of specific target mRNAs. We used long- and small-RNA sequencing to generate a detailed map of the transcriptome. Clusters of sRNAs marked the 5' end of all mature mRNAs. Their absence in M-factor mutants reflects the protection of transcript 5' end by the cognate factor. Enzymatic removal of 5'-triphosphates allowed identifying those cosRNA that mark a transcription start site. We detected another class of sRNAs derived from low abundance transcripts, antisense to mRNAs. The formation of antisense sRNAs required the presence of the complementary mRNA and was stimulated when translation was inhibited by chloramphenicol or lincomycin. We propose that they derive from degradation of double-stranded RNAs generated by pairing of antisense and sense transcripts, a process normally hindered by the traveling of the ribosomes. In addition, chloramphenicol treatment, by freezing ribosomes on the mRNA, caused the accumulation of 32-34 nt ribosome-protected fragments. Using this 'in vivo ribosome footprinting', we identified the function and molecular target of two candidate trans-acting factors.
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Affiliation(s)
- Marina Cavaiuolo
- Unité Mixte de Recherche 7141, CNRS/UPMC, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Richard Kuras
- Unité Mixte de Recherche 7141, CNRS/UPMC, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Francis‐André Wollman
- Unité Mixte de Recherche 7141, CNRS/UPMC, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Yves Choquet
- Unité Mixte de Recherche 7141, CNRS/UPMC, Institut de Biologie Physico-Chimique, F-75005 Paris, France
| | - Olivier Vallon
- Unité Mixte de Recherche 7141, CNRS/UPMC, Institut de Biologie Physico-Chimique, F-75005 Paris, France
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Novikova O, Belfort M. Mobile Group II Introns as Ancestral Eukaryotic Elements. Trends Genet 2017; 33:773-783. [PMID: 28818345 DOI: 10.1016/j.tig.2017.07.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 07/06/2017] [Accepted: 07/24/2017] [Indexed: 01/09/2023]
Abstract
The duality of group II introns, capable of carrying out both self-splicing and retromobility reactions, is hypothesized to have played a profound role in the evolution of eukaryotes. These introns likely provided the framework for the emergence of eukaryotic retroelements, spliceosomal introns and other key components of the spliceosome. Group II introns are found in all three domains of life and are therefore considered to be exceptionally successful mobile genetic elements. Initially identified in organellar genomes, group II introns are found in bacteria, chloroplasts, and mitochondria of plants and fungi, but not in nuclear genomes. Although there is no doubt that prokaryotic and organellar group II introns are evolutionary related, there are remarkable differences in survival strategies between them. Furthermore, an evolutionary relationship of group II introns to eukaryotic retroelements, including telomeres, and spliceosomes is unmistakable.
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Affiliation(s)
- Olga Novikova
- Department of Biological Sciences and RNA Institute, University at Albany, 1400 Washington Avenue, Albany, NY 12222, USA
| | - Marlene Belfort
- Department of Biological Sciences and RNA Institute, University at Albany, 1400 Washington Avenue, Albany, NY 12222, USA; Department of Biomedical Sciences, School of Public Health, University at Albany, 1400 Washington Avenue, Albany, NY 12222, USA.
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