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Lefebvre-Legendre L, Reifschneider O, Kollipara L, Sickmann A, Wolters D, Kück U, Goldschmidt-Clermont M. A pioneer protein is part of a large complex involved in trans-splicing of a group II intron in the chloroplast of Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 85:57-69. [PMID: 26611495 DOI: 10.1111/tpj.13089] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 11/17/2015] [Indexed: 05/08/2023]
Abstract
Splicing of organellar introns requires the activity of numerous nucleus-encoded factors. In the chloroplast of Chlamydomonas reinhardtii, maturation of psaA mRNA encoding photosystem I subunit A involves two steps of trans-splicing. The exons, located on three separate transcripts, are flanked by sequences that fold to form the conserved structures of two group II introns. A fourth transcript contributes to assembly of the first intron, which is thus tripartite. The raa7 mutant (RNA maturation of psaA 7) is deficient in trans-splicing of the second intron of psaA, and may be rescued by transforming the chloroplast genome with an intron-less version of psaA. Using mapped-based cloning, we identify the RAA7 locus, which encodes a pioneer protein with no previously known protein domain or motif. The Raa7 protein, which is not associated with membranes, localizes to the chloroplast. Raa7 is a component of a large complex and co-sediments in sucrose gradients with the previously described splicing factors Raa1 and Raa2. Based on tandem affinity purification of Raa7 and mass spectrometry, Raa1 and Raa2 were identified as interacting partners of Raa7. Yeast two-hybrid experiments indicate that the interaction of Raa7 with Raa1 and Raa2 may be direct. We conclude that Raa7 is a component of a multimeric complex that is required for trans-splicing of the second intron of psaA. The characterization of this psaA trans-splicing complex is also of interest from an evolutionary perspective because the nuclear spliceosomal introns are thought to derive from group II introns, with which they show mechanistic and structural similarity.
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Affiliation(s)
- Linnka Lefebvre-Legendre
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 30 quai Ernest Ansermet, 1211, Geneva 4, Switzerland
| | - Olga Reifschneider
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr University Bochum, Universitätsstraße 150, Bochum, 44801, Germany
| | - Laxmikanth Kollipara
- Leibniz-Institut für Analytische Wissenschaften- ISAS - e.V., Otto Hahn Straße 6b, Dortmund, 44227, Germany
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften- ISAS - e.V., Otto Hahn Straße 6b, Dortmund, 44227, Germany
- Department of Chemistry, College of Physical Sciences, University of Aberdeen, Aberdeen, UK
- Medizinische Fakultät, Medizinisches Proteom-Center, Ruhr-University Bochum, Universitätsstraße 150, Bochum, 44801, Germany
| | - Dirk Wolters
- Department of Analytical Chemistry, Ruhr-University Bochum, Universitätsstraße 150, Bochum, 44801, Germany
| | - Ulrich Kück
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr University Bochum, Universitätsstraße 150, Bochum, 44801, Germany
| | - Michel Goldschmidt-Clermont
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 30 quai Ernest Ansermet, 1211, Geneva 4, Switzerland
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Lefebvre-Legendre L, Choquet Y, Kuras R, Loubéry S, Douchi D, Goldschmidt-Clermont M. A nucleus-encoded chloroplast protein regulated by iron availability governs expression of the photosystem I subunit PsaA in Chlamydomonas reinhardtii. PLANT PHYSIOLOGY 2015; 167:1527-40. [PMID: 25673777 PMCID: PMC4378161 DOI: 10.1104/pp.114.253906] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The biogenesis of the photosynthetic electron transfer chain in the thylakoid membranes requires the concerted expression of genes in the chloroplast and the nucleus. Chloroplast gene expression is subjected to anterograde control by a battery of nucleus-encoded proteins that are imported in the chloroplast, where they mostly intervene at posttranscriptional steps. Using a new genetic screen, we identify a nuclear mutant that is required for expression of the PsaA subunit of photosystem I (PSI) in the chloroplast of Chlamydomonas reinhardtii. This mutant is affected in the stability and translation of psaA messenger RNA. The corresponding gene, TRANSLATION OF psaA1 (TAA1), encodes a large protein with two domains that are thought to mediate RNA binding: an array of octatricopeptide repeats (OPR) and an RNA-binding domain abundant in apicomplexans (RAP) domain. We show that as expected for its function, TAA1 is localized in the chloroplast. It was previously shown that when mixotrophic cultures of C. reinhardtii (which use both photosynthesis and mitochondrial respiration for growth) are shifted to conditions of iron limitation, there is a strong decrease in the accumulation of PSI and that this is rapidly reversed when iron is resupplied. Under these conditions, TAA1 protein is also down-regulated through a posttranscriptional mechanism and rapidly reaccumulates when iron is restored. These observations reveal a concerted regulation of PSI and of TAA1 in response to iron availability.
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Affiliation(s)
- Linnka Lefebvre-Legendre
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Yves Choquet
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Richard Kuras
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Sylvain Loubéry
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Damien Douchi
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Michel Goldschmidt-Clermont
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
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Targeted expression of nuclear transgenes in Chlamydomonas reinhardtii with a versatile, modular vector toolkit. Appl Microbiol Biotechnol 2015; 99:3491-503. [DOI: 10.1007/s00253-014-6354-7] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/09/2014] [Accepted: 12/22/2014] [Indexed: 12/13/2022]
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Jacobs J, Marx C, Kock V, Reifschneider O, Fränzel B, Krisp C, Wolters D, Kück U. Identification of a chloroplast ribonucleoprotein complex containing trans-splicing factors, intron RNA, and novel components. Mol Cell Proteomics 2013; 12:1912-25. [PMID: 23559604 PMCID: PMC3708175 DOI: 10.1074/mcp.m112.026583] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 02/27/2013] [Indexed: 11/06/2022] Open
Abstract
Maturation of chloroplast psaA pre-mRNA from the green alga Chlamydomonas reinhardtii requires the trans-splicing of two split group II introns. Several nuclear-encoded trans-splicing factors are required for the correct processing of psaA mRNA. Among these is the recently identified Raa4 protein, which is involved in splicing of the tripartite intron 1 of the psaA precursor mRNA. Part of this tripartite group II intron is the chloroplast encoded tscA RNA, which is specifically bound by Raa4. Using Raa4 as bait in a combined tandem affinity purification and mass spectrometry approach, we identified core components of a multisubunit ribonucleoprotein complex, including three previously identified trans-splicing factors (Raa1, Raa3, and Rat2). We further detected tscA RNA in the purified protein complex, which seems to be specific for splicing of the tripartite group II intron. A yeast-two hybrid screen and co-immunoprecipitation identified chloroplast-localized Raa4-binding protein 1 (Rab1), which specifically binds tscA RNA from the tripartite psaA group II intron. The yeast-two hybrid system provides evidence in support of direct interactions between Rab1 and four trans-splicing factors. Our findings contribute to our knowledge of chloroplast multisubunit ribonucleoprotein complexes and are discussed in support of the generally accepted view that group II introns are the ancestors of the eukaryotic spliceosomal introns.
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Affiliation(s)
- Jessica Jacobs
- From the ‡Department for General and Molecular Botany, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Christina Marx
- From the ‡Department for General and Molecular Botany, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Vera Kock
- From the ‡Department for General and Molecular Botany, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Olga Reifschneider
- From the ‡Department for General and Molecular Botany, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Benjamin Fränzel
- ¶Department of Analytical Chemistry, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Christoph Krisp
- ¶Department of Analytical Chemistry, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Dirk Wolters
- ¶Department of Analytical Chemistry, Ruhr-University Bochum, D-44780 Bochum, Germany
| | - Ulrich Kück
- From the ‡Department for General and Molecular Botany, Ruhr-University Bochum, D-44780 Bochum, Germany
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Cilia M, Peter KA, Bereman MS, Howe K, Fish T, Smith D, Gildow F, MacCoss MJ, Thannhauser TW, Gray SM. Discovery and targeted LC-MS/MS of purified polerovirus reveals differences in the virus-host interactome associated with altered aphid transmission. PLoS One 2012; 7:e48177. [PMID: 23118947 PMCID: PMC3484124 DOI: 10.1371/journal.pone.0048177] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 09/21/2012] [Indexed: 11/19/2022] Open
Abstract
Circulative transmission of viruses in the Luteoviridae, such as cereal yellow dwarf virus (CYDV), requires a series of precisely orchestrated interactions between virus, plant, and aphid proteins. Natural selection has favored these viruses to be retained in the phloem to facilitate acquisition and transmission by aphids. We show that treatment of infected oat tissue homogenate with sodium sulfite reduces transmission of the purified virus by aphids. Transmission electron microscopy data indicated no gross change in virion morphology due to treatments. However, treated virions were not acquired by aphids through the hindgut epithelial cells and were not transmitted when injected directly into the hemocoel. Analysis of virus preparations using nanoflow liquid chromatography coupled to tandem mass spectrometry revealed a number of host plant proteins co-purifying with viruses, some of which were lost following sodium sulfite treatment. Using targeted mass spectrometry, we show data suggesting that several of the virus-associated host plant proteins accumulated to higher levels in aphids that were fed on CYDV-infected plants compared to healthy plants. We propose two hypotheses to explain these observations, and these are not mutually exclusive: (a) that sodium sulfite treatment disrupts critical virion-host protein interactions required for aphid transmission, or (b) that host infection with CYDV modulates phloem protein expression in a way that is favorable for virus uptake by aphids. Importantly, the genes coding for the plant proteins associated with virus may be examined as targets in breeding cereal crops for new modes of virus resistance that disrupt phloem-virus or aphid-virus interactions.
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Affiliation(s)
- Michelle Cilia
- Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture-Agricultural Research Service, Ithaca, New York, United States of America
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, United States of America
- * E-mail: (MC); (SMG)
| | - Kari A. Peter
- Department of Plant Pathology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Michael S. Bereman
- Department of Genome Sciences, University of Washington, Seattle, Washington, United States of America
| | - Kevin Howe
- Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture-Agricultural Research Service, Ithaca, New York, United States of America
| | - Tara Fish
- Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture-Agricultural Research Service, Ithaca, New York, United States of America
| | - Dawn Smith
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, United States of America
| | - Fredrick Gildow
- Department of Plant Pathology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Michael J. MacCoss
- Department of Genome Sciences, University of Washington, Seattle, Washington, United States of America
| | - Theodore W. Thannhauser
- Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture-Agricultural Research Service, Ithaca, New York, United States of America
| | - Stewart M. Gray
- Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture-Agricultural Research Service, Ithaca, New York, United States of America
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, United States of America
- * E-mail: (MC); (SMG)
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Martin F. Fifteen years of the yeast three-hybrid system: RNA-protein interactions under investigation. Methods 2012; 58:367-75. [PMID: 22841566 DOI: 10.1016/j.ymeth.2012.07.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 05/04/2012] [Accepted: 07/13/2012] [Indexed: 01/14/2023] Open
Abstract
In 1996, the Wickens and the Kuhl labs developed the yeast three-hybrid system independently. By expressing two chimeric proteins and one chimeric RNA molecule in Saccharomyces cerevisiae, this method allows in vivo monitoring of RNA-protein interactions by measuring the expression levels of HIS3 and LacZ reporter genes. Specific RNA targets have been used to characterize unknown RNA binding proteins. Previously described RNA binding proteins have also been used as bait to select new RNA targets. Finally, this method has been widely used to investigate or confirm previously suspected RNA-protein interactions. However, this method falls short in some aspects, such as RNA display and selection of false positive molecules. This review will summarize the results obtained with this method from the past 15years, as well as on recent efforts to improve its specificity.
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Affiliation(s)
- Franck Martin
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, Institut de Biologie Moléculaire et Cellulaire, Strasbourg CEDEX, France.
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Glanz S, Jacobs J, Kock V, Mishra A, Kück U. Raa4 is a trans-splicing factor that specifically binds chloroplast tscA intron RNA. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 69:421-431. [PMID: 21954961 DOI: 10.1111/j.1365-313x.2011.04801.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
During trans-splicing of discontinuous organellar introns, independently transcribed coding sequences are joined together to generate a continuous mRNA. The chloroplast psaA gene from Chlamydomonas reinhardtii encoding the P(700) core protein of photosystem I (PSI) is split into three exons and two group IIB introns, which are both spliced in trans. Using forward genetics, we isolated a novel PSI mutant, raa4, with a defect in trans-splicing of the first intron. Complementation analysis identified the affected gene encoding the 112.4 kDa Raa4 protein, which shares no strong sequence identity with other known proteins. The chloroplast localization of the protein was confirmed by confocal fluorescence microscopy, using a GFP-tagged Raa4 fusion protein. RNA-binding studies showed that Raa4 binds specifically to domains D2 and D3, but not to other conserved domains of the tripartite group II intron. Raa4 may play a role in stabilizing folding intermediates or functionally active structures of the split intron RNA.
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Affiliation(s)
- Stephanie Glanz
- Department for General and Molecular Botany, Ruhr-University Bochum, D-44780 Bochum, Germany
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Bienvenut WV, Espagne C, Martinez A, Majeran W, Valot B, Zivy M, Vallon O, Adam Z, Meinnel T, Giglione C. Dynamics of post-translational modifications and protein stability in the stroma of Chlamydomonas reinhardtii chloroplasts. Proteomics 2011; 11:1734-50. [PMID: 21462344 DOI: 10.1002/pmic.201000634] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 11/10/2010] [Accepted: 11/29/2010] [Indexed: 01/09/2023]
Abstract
The proteome of any system is a dynamic entity dependent on the intracellular concentration of the entire set of expressed proteins. In turn, this whole protein concentration will be reliant on the stability/turnover of each protein as dictated by their relative rates of synthesis and degradation. In this study, we have investigated the dynamics of the stromal proteome in the model organism Chlamydomonas reinhardtii by characterizing the half-life of the whole set of proteins. 2-DE stromal proteins profiling was set up and coupled with MS analyses. These identifications featuring an average of 26% sequence coverage and eight non-redundant peptides per protein have been obtained for 600 independent samples related to 253 distinct spots. An interactive map of the global stromal proteome, of 274 distinct protein variants is now available on-line at http://www.isv.cnrs-gif.fr/gel2dv2/. N-α-terminal-Acetylation (NTA) was noticed to be the most frequently detectable post-translational modification, and new experimental data related to the chloroplastic transit peptide cleavage site was obtained. Using this data set supplemented with series of pulse-chase experiments, elements directing the relationship between half-life and N-termini were analyzed. Positive correlation between NTA and protein half-life suggests that NTA could contribute to protein stabilization in the stroma.
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Jacobs J, Kück U. Function of chloroplast RNA-binding proteins. Cell Mol Life Sci 2011; 68:735-48. [PMID: 20848156 PMCID: PMC11115000 DOI: 10.1007/s00018-010-0523-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 08/25/2010] [Accepted: 08/30/2010] [Indexed: 12/18/2022]
Abstract
Chloroplasts are eukaryotic organelles which represent evolutionary chimera with proteins that have been derived from either a prokaryotic endosymbiont or a eukaryotic host. Chloroplast gene expression starts with transcription of RNA and is followed by multiple post-transcriptional processes which are mediated mainly by an as yet unknown number of RNA-binding proteins. Here, we review the literature to date on the structure and function of these chloroplast RNA-binding proteins. For example, the functional protein domains involved in RNA binding, such as the RNA-recognition motifs, the chloroplast RNA-splicing and ribosome maturation domains, and the pentatricopeptide-repeat motifs, are summarized. We also describe biochemical and forward genetic approaches that led to the identification of proteins modifying RNA stability or carrying out RNA splicing or editing. Such data will greatly contribute to a better understanding of the biogenesis of a unique organelle found in all photosynthetic organisms.
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Affiliation(s)
- Jessica Jacobs
- Department for General and Molecular Biology, Ruhr-University Bochum, Universitätsstraße 150, Bochum, Germany.
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Jacobs J, Glanz S, Bunse-Grassmann A, Kruse O, Kück U. RNA trans-splicing: identification of components of a putative chloroplast spliceosome. Eur J Cell Biol 2010; 89:932-9. [PMID: 20705358 DOI: 10.1016/j.ejcb.2010.06.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Group II introns with highly complex RNA structures have been discovered in both prokaryotes and eukaryotic organelles. Usually, excision of non-coding group II intron sequences occurs by cis-splicing, the intramolecular ligation of exons in the same precursor RNA, but some group II introns are excised by intermolecular ligation. This process is called trans-splicing, and genome sequencing predicted that this type of RNA processing occurs in more than 180 organelle genomes from eukaryotes. A well characterised trans-spliced intron RNA is represented by the chloroplast psaA gene of the model alga Chlamydomonas reinhardtii. The psaA gene is split into three exons, which are widely distributed over the plastome and transcribed independently. PsaA exons are flanked by sequences typical for group II introns and joined by trans-splicing via two transesterification reactions. Although it is known that some group II introns are able to splice autocatalytically, trans-splicing of the psaA RNA depends on several nucleus and chloroplast encoded factors. The phylogenetic relationship between group II introns and nuclear spliceosomal RNA led to the hypothesis that these factors are part of large multiprotein and ribonucleoprotein complexes akin to the nuclear spliceosome. Here, we give a concise overview of experimental strategies to identify novel factors involved in trans-splicing of psaA RNA and review recent results that have elucidated the composition and function of a putative chloroplast spliceosome involved in processing of chloroplast precursor RNAs.
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Affiliation(s)
- Jessica Jacobs
- Department for General and Molecular Biology, Ruhr-University Bochum, 44780 Bochum, Germany
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Abstract
In eukaryotes, RNA trans-splicing is an important RNA-processing form for the end-to-end ligation of primary transcripts that are derived from separately transcribed exons. So far, three different categories of RNA trans-splicing have been found in organisms as diverse as algae to man. Here, we review one of these categories: the trans-splicing of discontinuous group II introns, which occurs in chloroplasts and mitochondria of lower eukaryotes and plants. Trans-spliced exons can be predicted from DNA sequences derived from a large number of sequenced organelle genomes. Further molecular genetic analysis of mutants has unravelled proteins, some of which being part of high-molecular-weight complexes that promote the splicing process. Based on data derived from the alga Chlamydomonas reinhardtii, a model is provided which defines the composition of an organelle spliceosome. This will have a general relevance for understanding the function of RNA-processing machineries in eukaryotic organelles.
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Affiliation(s)
- Stephanie Glanz
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität Bochum, Bochum, Germany
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13
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14
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Abstract
Group II introns are large autocatalytic RNAs found in organellar genomes of plants and lower eukaryotes, as well as in some bacterial genomes. Interestingly, these ribozymes share characteristic traits with both spliceosomal introns and non-LTR retrotransposons and may have a common evolutionary ancestor. Furthermore, group II intron features such as structure, folding and catalytic mechanism differ considerably from those of other large ribozymes, making group II introns an attractive model system to gain novel insights into RNA biology and biochemistry. This review explores recent advances in the structural and mechanistic characterization of group II intron architecture and self-splicing.
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Affiliation(s)
- Olga Fedorova
- Howard Hughes Medical Institute, Yale University, New Haven, CT 06520, USA.
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