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Mandáková T, Krumpolcová A, Matyášek R, Volkov R, Lysak MA, Kovařík A. Uniparental silencing of 5S rRNA genes in plant allopolyploids - insights from Cardamine (Brassicaceae). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 38838061 DOI: 10.1111/tpj.16850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/30/2024] [Accepted: 05/14/2024] [Indexed: 06/07/2024]
Abstract
While the phenomenon of uniparental silencing of 35S rDNA in interspecific hybrids and allopolyploids is well documented, there is a notable absence of information regarding whether such silencing extends to the 5S RNA component of ribosomes. To address this gap in knowledge, we analyzed the 5S and 35S rDNA expression in Cardamine (Brassicaceae) allopolyploids, namely C. × insueta (2n = 3x = 24, genome composition RRA), C. flexuosa (2n = 4x = 32, AAHH), and C. scutata (2n = 4x = 32, PPAA) which share a common diploid ancestor (AA). We employed high-throughput sequencing of transcriptomes and genomes and phylogenetic analyses of 5S rRNA variants. The genomic organization of rDNA was further scrutinized through clustering and fluorescence in situ hybridization. In the C. × insueta allotriploid, we observed uniparental dominant expression of 5S and 35S rDNA loci. In the C. flexuosa and C. scutata allotetraploids, the expression pattern differed, with the 35S rDNA being expressed from the A subgenome, whereas the 5S rDNA was expressed from the partner subgenome. Both C. flexuosa and C. scutata but not C. × insueta showed copy and locus number changes. We conclude that in stabilized allopolyploids, transcription of ribosomal RNA components occurs from different subgenomes. This phenomenon appears to result in the formation of chimeric ribosomes comprising rRNA molecules derived from distinct parental origins. We speculate that the interplay of epigenetic silencing and rDNA rearrangements introduces an additional layer of variation in multimolecule ribosomal complexes, potentially contributing to the evolutionary success of allopolyploids.
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Affiliation(s)
- Terezie Mandáková
- Central European Institute of Technology (CEITEC), Masaryk University, 625 00, Brno, Czech Republic
- Department of Experimental Biology, Faculty of Science, Masaryk University, 611 37, Brno, Czech Republic
| | - Alice Krumpolcová
- Department of Experimental Biology, Faculty of Science, Masaryk University, 611 37, Brno, Czech Republic
- Department of Molecular Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 00, Brno, Czech Republic
| | - Roman Matyášek
- Department of Molecular Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 00, Brno, Czech Republic
| | - Roman Volkov
- Department of Molecular Genetics and Biotechnology, Yuriy Fedkovych Chernivtsi National University, 58012, Chernivtsi, Ukraine
| | - Martin A Lysak
- Central European Institute of Technology (CEITEC), Masaryk University, 625 00, Brno, Czech Republic
- Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic
| | - Ales Kovařík
- Department of Molecular Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 00, Brno, Czech Republic
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Metabolic Survival Adaptations of Plasmodium falciparum Exposed to Sublethal Doses of Fosmidomycin. Antimicrob Agents Chemother 2021; 65:AAC.02392-20. [PMID: 33495219 DOI: 10.1128/aac.02392-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/05/2021] [Indexed: 12/17/2022] Open
Abstract
The malaria parasite Plasmodium falciparum contains the apicoplast organelle that synthesizes isoprenoids, which are metabolites necessary for posttranslational modification of Plasmodium proteins. We used fosmidomycin, an antibiotic that inhibits isoprenoid biosynthesis, to identify mechanisms that underlie the development of the parasite's adaptation to the drug at sublethal concentrations. We first determined a concentration of fosmidomycin that reduced parasite growth by ∼50% over one intraerythrocytic developmental cycle (IDC). At this dose, we maintained synchronous parasite cultures for one full IDC and collected metabolomic and transcriptomic data at multiple time points to capture global and stage-specific alterations. We integrated the data with a genome-scale metabolic model of P. falciparum to characterize the metabolic adaptations of the parasite in response to fosmidomycin treatment. Our simulations showed that, in treated parasites, the synthesis of purine-based nucleotides increased, whereas the synthesis of phosphatidylcholine during the trophozoite and schizont stages decreased. Specifically, the increased polyamine synthesis led to increased nucleotide synthesis, while the reduced methyl-group cycling led to reduced phospholipid synthesis and methyltransferase activities. These results indicate that fosmidomycin-treated parasites compensate for the loss of prenylation modifications by directly altering processes that affect nucleotide synthesis and ribosomal biogenesis to control the rate of RNA translation during the IDC. This also suggests that combination therapies with antibiotics that target the compensatory response of the parasite, such as nucleotide synthesis or ribosomal biogenesis, may be more effective than treating the parasite with fosmidomycin alone.
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3
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Stepanov VG, Fox GE. Expansion segments in bacterial and archaeal 5S ribosomal RNAs. RNA (NEW YORK, N.Y.) 2021; 27:133-150. [PMID: 33184227 PMCID: PMC7812874 DOI: 10.1261/rna.077123.120] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/09/2020] [Indexed: 05/10/2023]
Abstract
The large ribosomal RNAs of eukaryotes frequently contain expansion sequences that add to the size of the rRNAs but do not affect their overall structural layout and are compatible with major ribosomal function as an mRNA translation machine. The expansion of prokaryotic ribosomal RNAs is much less explored. In order to obtain more insight into the structural variability of these conserved molecules, we herein report the results of a comprehensive search for the expansion sequences in prokaryotic 5S rRNAs. Overall, 89 expanded 5S rRNAs of 15 structural types were identified in 15 archaeal and 36 bacterial genomes. Expansion segments ranging in length from 13 to 109 residues were found to be distributed among 17 insertion sites. The strains harboring the expanded 5S rRNAs belong to the bacterial orders Clostridiales, Halanaerobiales, Thermoanaerobacterales, and Alteromonadales as well as the archael order Halobacterales When several copies of a 5S rRNA gene are present in a genome, the expanded versions may coexist with normal 5S rRNA genes. The insertion sequences are typically capable of forming extended helices, which do not seemingly interfere with folding of the conserved core. The expanded 5S rRNAs have largely been overlooked in 5S rRNA databases.
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MESH Headings
- Alteromonadaceae/classification
- Alteromonadaceae/genetics
- Alteromonadaceae/metabolism
- Base Pairing
- Base Sequence
- Clostridiales/classification
- Clostridiales/genetics
- Clostridiales/metabolism
- Firmicutes/classification
- Firmicutes/genetics
- Firmicutes/metabolism
- Genome, Archaeal
- Genome, Bacterial
- Halobacteriales/classification
- Halobacteriales/genetics
- Halobacteriales/metabolism
- Nucleic Acid Conformation
- Phylogeny
- RNA, Archaeal/chemistry
- RNA, Archaeal/genetics
- RNA, Archaeal/metabolism
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Ribosomal, 5S/chemistry
- RNA, Ribosomal, 5S/genetics
- RNA, Ribosomal, 5S/metabolism
- Thermoanaerobacterium/classification
- Thermoanaerobacterium/genetics
- Thermoanaerobacterium/metabolism
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Affiliation(s)
- Victor G Stepanov
- Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204-5001, USA
| | - George E Fox
- Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204-5001, USA
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4
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Planktonic Euryarchaeota are a significant source of archaeal tetraether lipids in the ocean. Proc Natl Acad Sci U S A 2014; 111:9858-63. [PMID: 24946804 DOI: 10.1073/pnas.1409439111] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Archaea are ubiquitous in marine plankton, and fossil forms of archaeal tetraether membrane lipids in sedimentary rocks document their participation in marine biogeochemical cycles for >100 million years. Ribosomal RNA surveys have identified four major clades of planktonic archaea but, to date, tetraether lipids have been characterized in only one, the Marine Group I Thaumarchaeota. The membrane lipid composition of the other planktonic archaeal groups--all uncultured Euryarchaeota--is currently unknown. Using integrated nucleic acid and lipid analyses, we found that Marine Group II Euryarchaeota (MG-II) contributed significantly to the tetraether lipid pool in the North Pacific Subtropical Gyre at shallow to intermediate depths. Our data strongly suggested that MG-II also synthesize crenarchaeol, a tetraether lipid previously considered to be a unique biomarker for Thaumarchaeota. Metagenomic datasets spanning 5 y indicated that depth stratification of planktonic archaeal groups was a stable feature in the North Pacific Subtropical Gyre. The consistent prevalence of MG-II at depths where the bulk of exported organic matter originates, together with their ubiquitous distribution over diverse oceanic provinces, suggests that this clade is a significant source of tetraether lipids to marine sediments. Our results are relevant to archaeal lipid biomarker applications in the modern oceans and the interpretation of these compounds in the geologic record.
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Galián JA, Rosato M, Rosselló JA. Partial Sequence Homogenization in the 5S Multigene Families May Generate Sequence Chimeras and Spurious Results in Phylogenetic Reconstructions. Syst Biol 2014; 63:219-30. [DOI: 10.1093/sysbio/syt101] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- José A. Galián
- Jardín Botánico, Universidad de Valencia, c/Quart 80, E-46008 Valencia, Spain; and 2Marimurtra Bot. Garden, Carl Faust Fdn., PO Box 112, E-17300 Blanes, Catalonia, Spain
| | - Marcela Rosato
- Jardín Botánico, Universidad de Valencia, c/Quart 80, E-46008 Valencia, Spain; and 2Marimurtra Bot. Garden, Carl Faust Fdn., PO Box 112, E-17300 Blanes, Catalonia, Spain
| | - Josep A. Rosselló
- Jardín Botánico, Universidad de Valencia, c/Quart 80, E-46008 Valencia, Spain; and 2Marimurtra Bot. Garden, Carl Faust Fdn., PO Box 112, E-17300 Blanes, Catalonia, Spain
- Jardín Botánico, Universidad de Valencia, c/Quart 80, E-46008 Valencia, Spain; and 2Marimurtra Bot. Garden, Carl Faust Fdn., PO Box 112, E-17300 Blanes, Catalonia, Spain
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6
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Xu Z, Mathews DH. Multilign: an algorithm to predict secondary structures conserved in multiple RNA sequences. ACTA ACUST UNITED AC 2010; 27:626-32. [PMID: 21193521 DOI: 10.1093/bioinformatics/btq726] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
MOTIVATION With recent advances in sequencing, structural and functional studies of RNA lag behind the discovery of sequences. Computational analysis of RNA is increasingly important to reveal structure-function relationships with low cost and speed. The purpose of this study is to use multiple homologous sequences to infer a conserved RNA structure. RESULTS A new algorithm, called Multilign, is presented to find the lowest free energy RNA secondary structure common to multiple sequences. Multilign is based on Dynalign, which is a program that simultaneously aligns and folds two sequences to find the lowest free energy conserved structure. For Multilign, Dynalign is used to progressively construct a conserved structure from multiple pairwise calculations, with one sequence used in all pairwise calculations. A base pair is predicted only if it is contained in the set of low free energy structures predicted by all Dynalign calculations. In this way, Multilign improves prediction accuracy by keeping the genuine base pairs and excluding competing false base pairs. Multilign has computational complexity that scales linearly in the number of sequences. Multilign was tested on extensive datasets of sequences with known structure and its prediction accuracy is among the best of available algorithms. Multilign can run on long sequences (> 1500 nt) and an arbitrarily large number of sequences. AVAILABILITY The algorithm is implemented in ANSI C++ and can be downloaded as part of the RNAstructure package at: http://rna.urmc.rochester.edu.
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Affiliation(s)
- Zhenjiang Xu
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, NY, USA
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7
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Liu J, Ma B, Zhang K. An algorithm for searching RNA motifs in genomic sequences. ACTA ACUST UNITED AC 2007; 24:343-50. [PMID: 17482512 DOI: 10.1016/j.bioeng.2007.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Revised: 05/11/2006] [Accepted: 05/11/2006] [Indexed: 11/22/2022]
Abstract
RNA molecules, which are found in all living cells, fold into characteristic structures that account for their diverse functional activities. Many of these RNA structures consist of a collection of fundamental RNA motifs. The various combinations of RNA basic components form different RNA classes and define their unique structural and functional properties. The availability of many genome sequences makes it possible to search computationally for functional RNAs. Biological experiments indicate that functional RNAs have characteristic RNA structural motifs represented by specific combinations of base pairings and conserved nucleotides in the loop regions. The searching for those well-ordered RNA structures and their homologues in genomic sequences is very helpful for the understanding of RNA-based gene regulation. In this paper, we consider the following problem: given an RNA sequence with a known secondary structure, efficiently determine candidate segments in genomic sequences that can potentially form RNA secondary structures similar to the given RNA secondary structure. Our new bottom-up approach searches all potential stem-loops similar to ones of the given RNA secondary structure first, and then based on located stem-loops, detects potential homologous structural RNAs in genomic sequences.
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Affiliation(s)
- Jingping Liu
- Department of Computer Science, University of Western Ontario, London, Ontario, Canada.
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8
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El-Mabrouk N, Raffinot M, Duchesne JE, Lajoie M, Luc N. Approximate matching of structured motifs in DNA sequences. J Bioinform Comput Biol 2005; 3:317-42. [PMID: 15852508 DOI: 10.1142/s0219720005001065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Revised: 02/04/2004] [Accepted: 08/02/2004] [Indexed: 11/18/2022]
Abstract
Several methods have been developed for identifying more or less complex RNA structures in a genome. All these methods are based on the search for conserved primary and secondary sub-structures. In this paper, we present a simple formal representation of a helix, which is a combination of sequence and folding constraints, as a constrained regular expression. This representation allows us to develop a well-founded algorithm that searches for all approximate matches of a helix in a genome. The algorithm is based on an alignment graph constructed from several copies of a pushdown automaton, arranged one on top of another. This is a first attempt to take advantage of the possibilities of pushdown automata in the context of approximate matching. The worst time complexity is O(krpn), where k is the error threshold, n the size of the genome, p the size of the secondary expression, and r its number of union symbols. We then extend the algorithm to search for pseudo-knots and secondary structures containing an arbitrary number of helices.
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Affiliation(s)
- Nadia El-Mabrouk
- Département d'informatique et de recherche opérationnelle, Université de Montréal, CP 6128 Succursale Centre-ville, Montréal, Québec H3C 3J7.
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9
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Hirschhäuser S, Fröhlich J, Gneipel A, Schönig I, König H. Fast protocols for the 5S rDNA and ITS-2 based identification ofOenococcus oeni. FEMS Microbiol Lett 2005; 244:165-71. [PMID: 15727836 DOI: 10.1016/j.femsle.2005.01.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2004] [Revised: 11/30/2004] [Accepted: 01/20/2005] [Indexed: 11/21/2022] Open
Abstract
To identify specific marker sequences for the rapid identification of Oenococcus oeni, we sequenced the 23S-5S internal transcribed spacer (ITS-2) region and the 5S rDNA of five different O. oeni strains and three phylogenetically related lactic acid bacteria (LAB). Comparative analysis revealed 100% identity among the ITS-2 region of the O. oeni strains and remarkable differences in length and sequence compared to related LAB. These results enabled us to develop a primer set for a rapid PCR-identification of O. oeni within three hours. Moreover, the comparison of the 5S rDNA sequences and the highly conserved secondary structure provided the template for the design of three fluorescence-labeled specific oligonucleotides for fluorescence in situ hybridization (FISH). These probes are partial complementary to each other. This feature promotes the accessibility to the target sequence within the ribosome and enhances the fluorescence signal. For the rapid identification of Oenococci both the 5S rRNA gene and the ITS-2 region are useful targets.
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MESH Headings
- Base Sequence
- DNA, Bacterial/genetics
- DNA, Ribosomal/genetics
- DNA, Ribosomal Spacer/genetics
- Genes, Bacterial
- Gram-Positive Cocci/classification
- Gram-Positive Cocci/genetics
- Gram-Positive Cocci/isolation & purification
- In Situ Hybridization, Fluorescence
- Leuconostoc/classification
- Leuconostoc/genetics
- Leuconostoc/isolation & purification
- Molecular Sequence Data
- Nucleic Acid Conformation
- Polymerase Chain Reaction/methods
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Ribosomal, 5S/chemistry
- RNA, Ribosomal, 5S/genetics
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- Steffen Hirschhäuser
- Institute for Microbiology and Wine Research, Johannes Gutenberg University of Mainz, D-55128 Mainz, Germany
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10
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Deguilloux MF, Pemonge MH, Petit RJ. Novel perspectives in wood certification and forensics: dry wood as a source of DNA. Proc Biol Sci 2002; 269:1039-46. [PMID: 12028761 PMCID: PMC1690996 DOI: 10.1098/rspb.2002.1982] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The importance of wood for human societies can hardly be understated. If dry wood were amenable to molecular genetic investigations, this could lead to major applications in wood forensics, certification, archaeology and palaeobotany. To evaluate the potential of wood for molecular genetic investigations, we have attempted to isolate and amplify, by PCR, DNA fragments of increasing size corresponding to all three plant genomes from different regions of 10 oak logs. Stringent procedures to avoid contamination with external DNA were used in order to demonstrate the authenticity of the fragments amplified. This authenticity was further confirmed by demonstrating genetic uniformity within each log using both nuclear and chloroplast microsatellites. For most wood samples DNA was degraded, and the sequences that gave the best results were those of small size and present in high copy number (chloroplast, mitochondrial, or repeated nuclear sequences). Both storage conditions and storage duration play a role in DNA conservation. Overall, this work demonstrates that molecular markers from all three plant genomes can be used for genetic analysis on dry oak wood, but outlines some limitations and the need for further evaluation of the potential of wood for DNA analysis.
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Affiliation(s)
- Marie-France Deguilloux
- Institut National de la Recherche Agronomique, Station de Recherches Forestières, BP 45, F-33611 Gazinet cedex, France
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11
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Wyszko E, Barciszewska MZ, Bald R, Erdmann VA, Barciszewski J. The specific hydrolysis of HIV-1 TAR RNA element with the anti-TAR hammerhead ribozyme: structural and functional implications. Int J Biol Macromol 2001; 28:373-80. [PMID: 11325424 DOI: 10.1016/s0141-8130(01)00138-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The main transcriptional regulator of the human immunodeficiency virus is the Tat protein, which recognises and binds to a fragment RNA at the 5' end of viral mRNA, named transactivation response element (TAR) RNA. Extensive mutagenesis studies have shown that a region of TAR RNA important for Tat binding involves a set of nucleotides surrounding a characteristic UCU nucleotide bulge. The specific Tat-TAR complex formation enhances the rate of transcription elongation but inhibition of that interaction prevents the human immunodeficiency virus type 1 (HIV-1) replication. If so, a possibility of virus inactivation would be a site specific degradation of the TAR RNA element. To break down and inactivate TAR RNA, we designated the anti-hammerhead (HH) ribozyme to cleave nucleosides within the bulge. We showed for the first time the new type of the AUC hammerhead ribozyme, which hydrolyses specifically the TAR RNA element at C8 nucleotide in the bulge (C24 in the standard TAR RNA numbering). The cleavage reaction has broad magnesium requirements. Mn and particularly Ca are less efficient. Argininamide interferes with the cleavage of TAR RNA induced by the ribozyme. These results have two implications; (i) structural, where the HIV-1 TAR RNA element in solution occurs in equilibrium of only two forms, one of which, a double stranded RNA, meets structural requirements for ribozyme pairing and cleavage, and (ii) functional, the HH ribozyme can be explored for an inactivation of HIV-1 through the TAR RNA element deintegration.
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Affiliation(s)
- E Wyszko
- Institute of Bioorganic Chemistry of the Polish Academy of Sciences, Noskowskiego 12, 61794, Poznan, Poland
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12
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Xiong Y, Sundaralingam M. Two crystal forms of helix II of Xenopus laevis 5S rRNA with a cytosine bulge. RNA (NEW YORK, N.Y.) 2000; 6:1316-1324. [PMID: 10999608 PMCID: PMC1370004 DOI: 10.1017/s135583820000090x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The crystal structure of r(GCCACCCUG).r(CAGGGUCGGC), helix II of the Xenopus laevis 5S rRNA with a cytosine bulge (underlined), has been determined in two forms at 2.2 A (Form I, space group P4(2)2(1)2, a = b = 57.15 A and c = 43.54 A) and 1.7 A (Form II, space group P4(3)2(1)2, a = b = 32.78 A and c = 102.5 A). The helical regions of the nonamers are found in the standard A-RNA conformations and the two forms have an RMS deviation of 0.75 A. However, the cytosine bulge adopts two significantly different conformations with an RMS deviation of 3.9 A. In Form I, the cytosine bulge forms an intermolecular C+*G.C triple in the major groove of a symmetry-related duplex with intermolecular hydrogen bonds between N4C and O6G, and between protonated N3+C and N7G. In contrast, a minor groove C*G.C triple is formed in Form II with intermolecular hydrogen bonds between O2C and N2G, and between N3C and N3G with a water bridge. A partial major groove opening was observed in Form I structure at the bulge site. Two Ca2+ ions were found in Form I helix whereas there were none in Form II. The structural comparison of these two forms indicates that bulged residues can adopt a variety of conformations with little perturbation to the global helix structure. This suggests that bulged residues could function as flexible latches in bridging double helical motifs and facilitate the folding of large RNA molecules.
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Affiliation(s)
- Y Xiong
- The Ohio State University, Biological Macromolecular Structure Center, Department of Chemistry, Columbus 43210, USA
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13
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Dandekar T, Huynen M, Regula JT, Ueberle B, Zimmermann CU, Andrade MA, Doerks T, Sánchez-Pulido L, Snel B, Suyama M, Yuan YP, Herrmann R, Bork P. Re-annotating the Mycoplasma pneumoniae genome sequence: adding value, function and reading frames. Nucleic Acids Res 2000; 28:3278-88. [PMID: 10954595 PMCID: PMC110705 DOI: 10.1093/nar/28.17.3278] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Four years after the original sequence submission, we have re-annotated the genome of Mycoplasma pneumoniae to incorporate novel data. The total number of ORFss has been increased from 677 to 688 (10 new proteins were predicted in intergenic regions, two further were newly identified by mass spectrometry and one protein ORF was dismissed) and the number of RNAs from 39 to 42 genes. For 19 of the now 35 tRNAs and for six other functional RNAs the exact genome positions were re-annotated and two new tRNA(Leu) and a small 200 nt RNA were identified. Sixteen protein reading frames were extended and eight shortened. For each ORF a consistent annotation vocabulary has been introduced. Annotation reasoning, annotation categories and comparisons to other published data on M.pneumoniae functional assignments are given. Experimental evidence includes 2-dimensional gel electrophoresis in combination with mass spectrometry as well as gene expression data from this study. Compared to the original annotation, we increased the number of proteins with predicted functional features from 349 to 458. The increase includes 36 new predictions and 73 protein assignments confirmed by the published literature. Furthermore, there are 23 reductions and 30 additions with respect to the previous annotation. mRNA expression data support transcription of 184 of the functionally unassigned reading frames.
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Affiliation(s)
- T Dandekar
- EMBL, Postfach 102209, D-69012 Heidelberg, Germany, Max Delbrück Centre for Molecular Medicine, Robert-Rössle-Strabetae 10, 13092 Berlin-Buch, Germany
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14
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Sarzynska J, Kulinski T, Nilsson L. Conformational dynamics of a 5S rRNA hairpin domain containing loop D and a single nucleotide bulge. Biophys J 2000; 79:1213-27. [PMID: 10968986 PMCID: PMC1301018 DOI: 10.1016/s0006-3495(00)76376-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Molecular modeling and molecular dynamics have been employed to study the conformation and flexibility of a 15-nucleotide fragment of the plant 5S rRNA containing loop D and a single uridine bulge. Two different model built initial structures were used: one with the bulge localized inside the helical stem and another with the bulge pointing out from the helix. Several independent 700-ps-long trajectories in aqueous solution with Na(+) conterions were produced for each starting structure. The bulge nucleotide inside the helix stayed in two main conformations, both of which affected the geometry of the stem part opposite the bulge. When the bulge nucleotide was located outside the helix, we found high base mobility and local backbone flexibility. The dynamics of the hydrogen bond network and conformational changes from a direct to a water mediated hydrogen bond in the sheared G-A basepair in the tetraloop was described. Our results correlate with lead ion induced cleavage patterns in 5S rRNA. Sites resistant to nonspecific lead cleavage appeared in all our simulations as the most rigid fragments independent of the localization of the bulge nucleotide.
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Affiliation(s)
- J Sarzynska
- Center for Structural Biochemistry, Department of Bioscience at NOVUM, Karolinska Institutet, SE-141 57 Huddinge, Sweden
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15
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Maiwald M, von Herbay A, Lepp PW, Relman DA. Organization, structure, and variability of the rRNA operon of the Whipple's disease bacterium (Tropheryma whippelii). J Bacteriol 2000; 182:3292-7. [PMID: 10809715 PMCID: PMC94522 DOI: 10.1128/jb.182.11.3292-3297.2000] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/1999] [Accepted: 03/12/2000] [Indexed: 11/20/2022] Open
Abstract
Whipple's disease is a systemic disorder associated with a cultivation-resistant, poorly characterized actinomycete, Tropheryma whippelii. We determined a nearly complete rRNA operon sequence of T. whippelii from specimens from 3 patients with Whipple's disease, as well as partial operon sequences from 43 patients. Variability was observed in the 16S-23S rRNA spacer sequences, leading to the description of five distinct sequence types. One specimen contained two spacer sequence types, raising the possibility of a double infection. Secondary structure models for the primary rRNA transcript and mature rRNAs revealed rare or unique features.
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Affiliation(s)
- M Maiwald
- Departments of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA
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Szymanski M, Barciszewska MZ, Barciszewski J, Erdmann VA. 5S ribosomal RNA database Y2K. Nucleic Acids Res 2000; 28:166-7. [PMID: 10592212 PMCID: PMC102473 DOI: 10.1093/nar/28.1.166] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This paper presents the updated version (Y2K) of the database of ribosomal 5S ribonucleic acids (5S rRNA) and their genes (5S rDNA), http://rose.man/poznan.pl/5SData/index.html. This edition of the database contains 1985primary structures of 5S rRNA and 5S rDNA. They include 60 archaebacterial, 470 eubacterial, 63 plastid, nine mitochondrial and 1383 eukaryotic sequences. The nucleotide sequences of the 5S rRNAs or 5S rDNAs are divided according to the taxonomic position of the source organisms.
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Affiliation(s)
- M Szymanski
- Institute of Bioorganic Chemistry of the Polish Academy of Sciences, Noskowskiego 12, 61704 Poznan, Poland
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