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Malcicka M, Ruther J, Ellers J. De novo Synthesis of Linoleic Acid in Multiple Collembola Species. J Chem Ecol 2017; 43:911-919. [DOI: 10.1007/s10886-017-0878-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/24/2017] [Accepted: 08/09/2017] [Indexed: 01/15/2023]
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Dong Y, Zhu L, Bai Y, Ou Y, Wang C. Complete mitochondrial genomes of two flat-backed millipedes by next-generation sequencing (Diplopoda, Polydesmida). Zookeys 2017:1-20. [PMID: 28138271 PMCID: PMC5240118 DOI: 10.3897/zookeys.637.9909] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Accepted: 11/17/2016] [Indexed: 11/30/2022] Open
Abstract
A lack of mitochondrial genome data from myriapods is hampering progress across genetic, systematic, phylogenetic and evolutionary studies. Here, the complete mitochondrial genomes of two millipedes, Asiomorphacoarctata Saussure, 1860 (Diplopoda: Polydesmida: Paradoxosomatidae) and Xystodesmus sp. (Diplopoda: Polydesmida: Xystodesmidae) were assembled with high coverage using Illumina sequencing data. The mitochondrial genomes of the two newly sequenced species are circular molecules of 15,644 bp and 15,791 bp, within which the typical mitochondrial genome complement of 13 protein-coding genes, 22 tRNAs and two ribosomal RNA genes could be identified. The mitochondrial genome of Asiomorphacoarctata is the first complete sequence in the family Paradoxosomatidae (Diplopoda: Polydesmida) and the gene order of the two flat-backed millipedes is novel among known myriapod mitochondrial genomes. Unique translocations have occurred, including inversion of one half of the two genomes with respect to other millipede genomes. Inversion of the entire side of a genome (trnF-nad5-trnH-nad4-nad4L, trnP, nad1-trnL2-trnL1-rrnL-trnV-rrnS, trnQ, trnC and trnY) could constitute a common event in the order Polydesmida. Last, our phylogenetic analyses recovered the monophyletic Progoneata, subphylum Myriapoda and four internal classes.
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Affiliation(s)
- Yan Dong
- College of Biology and Food Engineering, Chuzhou University, Chuzhou 239000, China
| | - Lixin Zhu
- College of Biology and Food Engineering, Chuzhou University, Chuzhou 239000, China
| | - Yu Bai
- College of Biology and Food Engineering, Chuzhou University, Chuzhou 239000, China
| | - Yongyue Ou
- College of Biology and Food Engineering, Chuzhou University, Chuzhou 239000, China
| | - Changbao Wang
- College of Biology and Food Engineering, Chuzhou University, Chuzhou 239000, China
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Stokkan M, Jurado-Rivera JA, Juan C, Jaume D, Pons J. Mitochondrial genome rearrangements at low taxonomic levels: three distinct mitogenome gene orders in the genus Pseudoniphargus (Crustacea: Amphipoda). Mitochondrial DNA A DNA Mapp Seq Anal 2015; 27:3579-89. [PMID: 26329687 DOI: 10.3109/19401736.2015.1079821] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A comparison of mitochondrial genomes of three species of the amphipod Pseudoniphargus revealed the occurrence of a surprisingly high level of gene rearrangement involving protein-coding genes that is a rare phenomenon at low taxonomic levels. The three Pseudoniphargus mitogenomes also display a unique gene arrangement with respect to either the presumed Pancrustacean order or those known for other amphipods. Relative long non-coding sequences appear adjacent to the putative breakage points involved in gene rearrangements of protein coding genes. Other details of the newly obtained mitochondrial genomes - e.g., gene content, nucleotide composition and codon usage - are similar to those found in the mitogenomes of other amphipod species studied. They all contain the typical mitochondrial genome set consisting of 13 protein-coding genes, 22 tRNAs, and two rRNAS, as well as a large control region. The secondary structures and characteristics of tRNA and ribosomal mitochondrial genes of these three species are also discussed.
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Affiliation(s)
- Morten Stokkan
- a Department of Biodiversity and Conservation , Instituto Mediterraneo de Estudios Avanzados (IMEDEA, CSIC-UIB) , Esporles , Spain and
| | - Jose A Jurado-Rivera
- a Department of Biodiversity and Conservation , Instituto Mediterraneo de Estudios Avanzados (IMEDEA, CSIC-UIB) , Esporles , Spain and.,b Departament de Biologia , Universitat de les Illes Balears , Palma , Spain
| | - Carlos Juan
- a Department of Biodiversity and Conservation , Instituto Mediterraneo de Estudios Avanzados (IMEDEA, CSIC-UIB) , Esporles , Spain and.,b Departament de Biologia , Universitat de les Illes Balears , Palma , Spain
| | - Damià Jaume
- a Department of Biodiversity and Conservation , Instituto Mediterraneo de Estudios Avanzados (IMEDEA, CSIC-UIB) , Esporles , Spain and
| | - Joan Pons
- a Department of Biodiversity and Conservation , Instituto Mediterraneo de Estudios Avanzados (IMEDEA, CSIC-UIB) , Esporles , Spain and
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Pons J, Bauzà-Ribot MM, Jaume D, Juan C. Next-generation sequencing, phylogenetic signal and comparative mitogenomic analyses in Metacrangonyctidae (Amphipoda: Crustacea). BMC Genomics 2014; 15:566. [PMID: 24997985 PMCID: PMC4112215 DOI: 10.1186/1471-2164-15-566] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/26/2014] [Indexed: 11/16/2022] Open
Abstract
Background Comparative mitochondrial genomic analyses are rare among crustaceans below the family or genus level. The obliged subterranean crustacean amphipods of the family Metacrangonyctidae, found from the Hispaniola (Antilles) to the Middle East, including the Canary Islands and the peri-Mediterranean region, have an evolutionary history and peculiar biogeography that can respond to Tethyan vicariance. Indeed, recent phylogenetic analysis using all protein-coding mitochondrial sequences and one nuclear ribosomal gene have lent support to this hypothesis (Bauzà-Ribot et al. 2012). Results We present the analyses of mitochondrial genome sequences of 21 metacrangonyctids in the genera Metacrangonyx and Longipodacrangonyx, covering the entire geographical range of the family. Most mitogenomes were attained by next-generation sequencing techniques using long-PCR fragments sequenced by Roche FLX/454 or GS Junior pyro-sequencing, obtaining a coverage depth per nucleotide of up to 281×. All mitogenomes were AT-rich and included the usual 37 genes of the metazoan mitochondrial genome, but showed a unique derived gene order not matched in any other amphipod mitogenome. We compare and discuss features such as strand bias, phylogenetic informativeness, non-synonymous/synonymous substitution rates and other mitogenomic characteristics, including ribosomal and transfer RNAs annotation and structure. Conclusions Next-generation sequencing of pooled long-PCR amplicons can help to rapidly generate mitogenomic information of a high number of related species to be used in phylogenetic and genomic evolutionary studies. The mitogenomes of the Metacrangonyctidae have the usual characteristics of the metazoan mitogenomes (circular molecules of 15,000-16,000 bp, coding for 13 protein genes, 22 tRNAs and two ribosomal genes) and show a conserved gene order with several rearrangements with respect to the presumed Pancrustacean ground pattern. Strand nucleotide bias appears to be reversed with respect to the condition displayed in the majority of crustacean mitogenomes since metacrangonyctids show a GC-skew at the (+) and (-) strands; this feature has been reported also in the few mitogenomes of Isopoda (Peracarida) known thus far. The features of the rRNAs, tRNAs and sequence motifs of the control region of the Metacrangonyctidae are similar to those of the few crustaceans studied at present. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-566) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Joan Pons
- IMEDEA (CSIC-UIB), Mediterranean Institute for Advanced Studies, c/Miquel Marquès 21, 07190 Esporles, Spain.
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Streicher JW, García-Vázquez UO, Ponce-Campos P, Flores-Villela O, Campbell JA, Smith EN. Evolutionary relationships amongst polymorphic direct-developing frogs in theCraugastor rhodopisSpecies Group (Anura: Craugastoridae). SYST BIODIVERS 2014. [DOI: 10.1080/14772000.2014.882428] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Chen WJ, Koch M, Mallatt JM, Luan YX. Comparative analysis of mitochondrial genomes in Diplura (hexapoda, arthropoda): taxon sampling is crucial for phylogenetic inferences. Genome Biol Evol 2014; 6:105-20. [PMID: 24391151 PMCID: PMC3914688 DOI: 10.1093/gbe/evt207] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2013] [Indexed: 11/14/2022] Open
Abstract
Two-pronged bristletails (Diplura) are traditionally classified into three major superfamilies: Campodeoidea, Projapygoidea, and Japygoidea. The interrelationships of these three superfamilies and the monophyly of Diplura have been much debated. Few previous studies included Projapygoidea in their phylogenetic considerations, and its position within Diplura still is a puzzle from both morphological and molecular points of view. Until now, no mitochondrial genome has been sequenced for any projapygoid species. To fill in this gap, we determined and annotated the complete mitochondrial genome of Octostigma sinensis (Octostigmatidae, Projapygoidea), and of three more dipluran species, one each from the Campodeidae, Parajapygidae, and Japygidae. All four newly sequenced dipluran mtDNAs encode the same set of genes in the same gene order as shared by most crustaceans and hexapods. Secondary structure truncations have occurred in trnR, trnC, trnS1, and trnS2, and the reduction of transfer RNA D-arms was found to be taxonomically correlated, with Campodeoidea having experienced the most reduction. Partitioned phylogenetic analyses, based on both amino acids and nucleotides of the protein-coding genes plus the ribosomal RNA genes, retrieve significant support for a monophyletic Diplura within Pancrustacea, with Projapygoidea more closely related to Campodeoidea than to Japygoidea. Another key finding is that monophyly of Diplura cannot be recovered unless Projapygoidea is included in the phylogenetic analyses; this explains the dipluran polyphyly found by past mitogenomic studies. Including Projapygoidea increased the sampling density within Diplura and probably helped by breaking up a long-branch-attraction artifact. This finding provides an example of how proper sampling is significant for phylogenetic inference.
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Affiliation(s)
- Wan-Jun Chen
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology & Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Markus Koch
- Biocentre Grindel and Zoological Museum, University of Hamburg, Germany
| | - Jon M. Mallatt
- School of Biological Sciences, Washington State University
| | - Yun-Xia Luan
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology & Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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Complete Mitochondrial Genome Sequence of Acrida cinerea (Acrididae: Orthoptera) and Comparative Analysis of Mitochondrial Genomes in Orthoptera. Comp Funct Genomics 2010; 2010:319486. [PMID: 21197069 PMCID: PMC3004375 DOI: 10.1155/2010/319486] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Revised: 08/02/2010] [Accepted: 09/02/2010] [Indexed: 11/19/2022] Open
Abstract
The complete 15,599-bp mitogenome of Acrida cinerea was determined and compared with that of the other 20 orthopterans. It displays characteristic gene content, genome organization, nucleotide composition, and codon usage found in other Caelifera mitogenomes. Comparison of 21 orthopteran sequences revealed that the tRNAs encoded by the H-strand appear more conserved than those by the L-stand. All tRNAs form the typical clover-leaf structure except trnS (agn), and most of the size variation among tRNAs stemmed from the length variation in the arm and loop of TΨC and the loop of DHU. The derived secondary structure models of the rrnS and rrnL from 21 orthoptera species closely resemble those from other insects on CRW except a considerably enlarged loop of helix 1399 of rrnS in Caelifera, which is a potentially autapomorphy of Caelifera. In the A+T-rich region, tandem repeats are not only conserved in the closely related mitogenome but also share some conserved motifs in the same subfamily. A stem-loop structure, 16 bp or longer, is likely to be involved in replication initiation in Caelifera and Grylloidea. A long T-stretch (>17 bp) with conserved stem-loop structure next to rrnS on the H-strand, bounded by a purine at either end, exists in the three species from Tettigoniidae.
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Mitochondrial rRNA secondary structures and genome arrangements distinguish chelicerates: comparisons with a harvestman (Arachnida: Opiliones: Phalangium opilio). Gene 2009; 449:9-21. [PMID: 19800399 DOI: 10.1016/j.gene.2009.09.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 09/20/2009] [Accepted: 09/22/2009] [Indexed: 11/23/2022]
Abstract
Arachnids are a highly diverse group of arthropods, and many of the mitochondrial genomes that have been sequenced from arachnids possess unusual features in their inferred gene structures and genome organization. The first complete sequence of a mitochondrial genome from the arachnid order Opiliones (harvestmen) is presented here. Secondary structures of the two mitochondrial ribosomal subunits of Phalangium opilio are inferred and compared to mitochondrial rRNA structures of a hexapod and a chelicerate. The large subunit rRNA of P. opilio is found to have more helices conserved than in other arthropods, while the small subunit rRNA shows a complexity similar to that of other arthropods. These comparisons suggest that a reduction in rRNA complexity occurred in Pancrustacea after the divergence of Pancrustacea and Chelicerata from a common ancestor. The gene arrangement of the mitochondrial genome of P. opilio is compared with the gene order of taxa from all seven other orders of arachnids for which representative mitochondrial genomes have been sequenced. Taxa from five of these seven orders possess gene arrangements identical to that of Limulus polyphemus, and P. opilio is found to have a similar arrangement. However, in P. opilio, some genes near the putative control region are rearranged, with the suite of genes encoding tRNA(Gln), the control region, and tRNA(Ile) located downstream of the two ribosomal RNA genes, and upstream of where they are typically located in chelicerates. The genome encodes only 21 of the typical 22 mitochondrial tRNA genes and lacks the gene for tRNA(Leu(CUN)). The protein-coding genes in the mitochondrial genome of P. opilio show a significantly decreased use of codons recognized by tRNA(Leu(CUN)), likely due to selection to utilize the more specific tRNA(Leu(UUR)) anticodon. The gene arrangement and lack of a tRNA(Leu(CUN)) gene in P. opilio is most parsimoniously explained by the occurrence of at least two translocation events, one of which probably destroyed the function of the tRNA(Leu(CUN)) gene. Phylogenetic relationships among the major orders of arachnids are inferred, using all 13 mt protein-coding genes, and gene rearrangements are mapped onto the phylogeny. The phylogenetic analyses are unable to resolve the placement of P. opilio but are generally consistent with an early divergence of members of the Dromopoda (harvestmen, scorpions, and solifuges) from the Micruran arachnids (spiders, whip spiders, vinegaroons, ricinuleids, and mites). However, unlike some morphologically based phylogenetic analyses, the existence of a clade of Dromopoda is not supported. While data on genome arrangement and gene loss do not provide further information to help resolve relationships among the arachnid orders, they distinguish some groups of arachnids, distinguish chelicerates from other arthropods, and further clarify the ancestral gene order of this diverse group of arthropods.
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Fleck G, Ullrich B, Brenk M, Wallnisch C, Orland M, Bleidissel S, Misof B. A phylogeny of anisopterous dragonflies (Insecta, Odonata) using mtRNA genes and mixed nucleotide/doublet models. J ZOOL SYST EVOL RES 2008. [DOI: 10.1111/j.1439-0469.2008.00474.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Carapelli A, Comandi S, Convey P, Nardi F, Frati F. The complete mitochondrial genome of the Antarctic springtail Cryptopygus antarcticus (Hexapoda: Collembola). BMC Genomics 2008; 9:315. [PMID: 18593463 PMCID: PMC2483729 DOI: 10.1186/1471-2164-9-315] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Accepted: 07/01/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mitogenomics data, i.e. complete mitochondrial genome sequences, are popular molecular markers used for phylogenetic, phylogeographic and ecological studies in different animal lineages. Their comparative analysis has been used to shed light on the evolutionary history of given taxa and on the molecular processes that regulate the evolution of the mitochondrial genome. A considerable literature is available in the fields of invertebrate biochemical and ecophysiological adaptation to extreme environmental conditions, exemplified by those of the Antarctic. Nevertheless, limited molecular data are available from terrestrial Antarctic species, and this study represents the first attempt towards the description of a mitochondrial genome from one of the most widespread and common collembolan species of Antarctica. RESULTS In this study we describe the mitochondrial genome of the Antarctic collembolan Cryptopygus antarcticus Willem, 1901. The genome contains the standard set of 37 genes usually present in animal mtDNAs and a large non-coding fragment putatively corresponding to the region (A+T-rich) responsible for the control of replication and transcription. All genes are arranged in the gene order typical of Pancrustacea. Three additional short non-coding regions are present at gene junctions. Two of these are located in positions of abrupt shift of the coding polarity of genes oriented on opposite strands suggesting a role in the attenuation of the polycistronic mRNA transcription(s). In addition, remnants of an additional copy of trnL(uag) are present between trnS(uga) and nad1. Nucleotide composition is biased towards a high A% and T% (A+T = 70.9%), as typically found in hexapod mtDNAs. There is also a significant strand asymmetry, with the J-strand being more abundant in A and C. Within the A+T-rich region, some short sequence fragments appear to be similar (in position and primary sequence) to those involved in the origin of the N-strand replication of the Drosophila mtDNA. CONCLUSION The mitochondrial genome of C. antarcticus shares several features with other pancrustacean genomes, although the presence of unusual non-coding regions is also suggestive of molecular rearrangements that probably occurred before the differentiation of major collembolan families. Closer examination of gene boundaries also confirms previous observations on the presence of unusual start and stop codons, and suggests a role for tRNA secondary structures as potential cleavage signals involved in the maturation of the primary transcript. Sequences potentially involved in the regulation of replication/transcription are present both in the A+T-rich region and in other areas of the genome. Their position is similar to that observed in a limited number of insect species, suggesting unique replication/transcription mechanisms for basal and derived hexapod lineages. This initial description and characterization of the mitochondrial genome of C. antarcticus will constitute the essential foundation prerequisite for investigations of the evolutionary history of one of the most speciose collembolan genera present in Antarctica and other localities of the Southern Hemisphere.
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Affiliation(s)
- Antonio Carapelli
- Department of Evolutionary Biology, University of Siena, Via A, Moro 2, 53100 Siena, Italy.
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Gillespie JJ, Johnston JS, Cannone JJ, Gutell RR. Characteristics of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) rRNA genes of Apis mellifera (Insecta: Hymenoptera): structure, organization, and retrotransposable elements. INSECT MOLECULAR BIOLOGY 2006; 15:657-86. [PMID: 17069639 PMCID: PMC2048585 DOI: 10.1111/j.1365-2583.2006.00689.x] [Citation(s) in RCA: 189] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2006] [Accepted: 06/28/2006] [Indexed: 05/12/2023]
Abstract
As an accompanying manuscript to the release of the honey bee genome, we report the entire sequence of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) ribosomal RNA (rRNA)-encoding gene sequences (rDNA) and related internally and externally transcribed spacer regions of Apis mellifera (Insecta: Hymenoptera: Apocrita). Additionally, we predict secondary structures for the mature rRNA molecules based on comparative sequence analyses with other arthropod taxa and reference to recently published crystal structures of the ribosome. In general, the structures of honey bee rRNAs are in agreement with previously predicted rRNA models from other arthropods in core regions of the rRNA, with little additional expansion in non-conserved regions. Our multiple sequence alignments are made available on several public databases and provide a preliminary establishment of a global structural model of all rRNAs from the insects. Additionally, we provide conserved stretches of sequences flanking the rDNA cistrons that comprise the externally transcribed spacer regions (ETS) and part of the intergenic spacer region (IGS), including several repetitive motifs. Finally, we report the occurrence of retrotransposition in the nuclear large subunit rDNA, as R2 elements are present in the usual insertion points found in other arthropods. Interestingly, functional R1 elements usually present in the genomes of insects were not detected in the honey bee rRNA genes. The reverse transcriptase products of the R2 elements are deduced from their putative open reading frames and structurally aligned with those from another hymenopteran insect, the jewel wasp Nasonia (Pteromalidae). Stretches of conserved amino acids shared between Apis and Nasonia are illustrated and serve as potential sites for primer design, as target amplicons within these R2 elements may serve as novel phylogenetic markers for Hymenoptera. Given the impending completion of the sequencing of the Nasonia genome, we expect our report eventually to shed light on the evolution of the hymenopteran genome within higher insects, particularly regarding the relative maintenance of conserved rDNA genes, related variable spacer regions and retrotransposable elements.
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Affiliation(s)
- J J Gillespie
- Department of Entomology, Texas A & M University, College Station, TX, USA.
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Carapelli A, Vannini L, Nardi F, Boore JL, Beani L, Dallai R, Frati F. The mitochondrial genome of the entomophagous endoparasite Xenos vesparum (Insecta: Strepsiptera). Gene 2006; 376:248-59. [PMID: 16766140 DOI: 10.1016/j.gene.2006.04.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 03/21/2006] [Accepted: 04/08/2006] [Indexed: 11/25/2022]
Abstract
In this study, the nearly complete sequence (14,519 bp) of the mitochondrial DNA (mtDNA) of the entomophagous endoparasite Xenos vesparum (Insecta: Strepsiptera) is described. All protein coding genes (PCGs) are in the arrangement known to be ancestral for insects, but three tRNA genes (trnA, trnS(gcu), and trnL(uag)) have transposed to derived positions and there are three tandem copies of trnH, each of which is potentially functional. All of these rearrangements except for that of trnL(uag) is within the short span between nad3 and nad4 and there are numerous blocks of unassignable sequence in this region, perhaps as remnants of larger scale predisposing rearrangements. X. vesparum mtDNA nucleotide composition is strongly biased toward A and T, as is typical for insect mtDNAs. There is also a significant strand skew in the distribution of these nucleotides, with the J-strand being richer in A than T and in C than G, and the N-strand showing an opposite skew for complementary pairs of nucleotides. The hypothetical secondary structure of the LSU rRNA has also been reconstructed, obtaining a structural model similar to that of other insects.
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MESH Headings
- Animals
- Base Composition
- Base Pairing
- Base Sequence
- Codon
- DNA, Circular/chemistry
- DNA, Circular/genetics
- DNA, Mitochondrial/chemistry
- DNA, Mitochondrial/genetics
- Evolution, Molecular
- Gene Dosage
- Gene Expression Profiling
- Gene Order
- Gene Rearrangement
- Genes, Insect
- Genome
- Insecta/classification
- Insecta/genetics
- Microsatellite Repeats
- Molecular Sequence Data
- Nucleic Acid Conformation
- Open Reading Frames
- RNA, Ribosomal/chemistry
- RNA, Ribosomal/genetics
- RNA, Transfer/chemistry
- RNA, Transfer/genetics
- Repetitive Sequences, Nucleic Acid
- Sequence Analysis, DNA
- Translocation, Genetic
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Hypsa V. Parasite histories and novel phylogenetic tools: Alternative approaches to inferring parasite evolution from molecular markers. Int J Parasitol 2006; 36:141-55. [PMID: 16387305 DOI: 10.1016/j.ijpara.2005.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Revised: 10/19/2005] [Accepted: 10/28/2005] [Indexed: 10/25/2022]
Abstract
Parasitological research is often contingent on the knowledge of the phylogeny/genealogy of the studied group. Although molecular phylogenetics has proved to be a powerful tool in such investigations, its application in the traditional fashion, based on a tree inference from the primary nucleotide sequences may, in many cases, be insufficient or even improper. These limitations are due to a number of factors, such as a scarcity/ambiguity of phylogenetic information in the sequences, an intricacy of gene relationships at low phylogenetic levels, or a lack of criteria when deciding among several competing coevolutionary scenarios. With respect to the importance of a precise and reliable phylogenetic background in many biological studies, attempts are being made to extend molecular phylogenetics with a variety of new data sources and methodologies. In this review, selected approaches potentially applicable to parasitological research are presented and their advantages as well as drawbacks are discussed. These issues include the usage of idiosyncratic markers (unique features with presumably low probability of homoplasy), such as insertion of mobile elements, gene rearrangements and secondary structure features; the problem of ancestral polymorphism and reticulate relationships at low phylogenetic levels; and the utility of a molecular clock to facilitate discrimination among alternative scenarios in host-parasite coevolution.
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Affiliation(s)
- Václav Hypsa
- Faculty of Biological Sciences, University of South Bohemia, and Institute of Parasitology, Academy of Sciences of the Czech Republic, Branisovská 31, 37005 Ceské Budejovice, Czech Republic.
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