Evolution of the Xenopus piggyBac Transposon Family TxpB:
          Domesticated and Untamed Strategies of Transposon Subfamilies

Abstract A new family, termed TxpB, of DNA transposons belonging to the piggyBac superfamily was found in 3 Xenopus species (Xenopus tropicalis, Xenopus laevis, and Xenopus borealis). Two TxpB subfamilies of Kobuta and Uribo1 were found in all the 3 species, and another subfamily termed Uribo2 was found in X. tropicalis. Molecular phylogenetic analyses of their open reading frames (ORFs) revealed that TxpB transposons have been maintained for over 100 Myr. Both the Uribo1 and the Uribo2 ORFs were present as multiple copies in each genome, and some of them were framed by terminal inverted repeat sequences. In contrast, all the Kobuta ORFs were present as a single copy in each genome and exhibited high evolutionary conservation, suggesting domestication of Kobuta genes by the host. Genomic insertion polymorphisms of the Uribo1 and Uribo2 transposons (nonautonomous type) were observed in a single species of X. tropicalis, indicating recent transposition events. Transfection experiments in cell culture revealed that an expression vector construct for the intact Uribo2 ORF caused precise excision of a nonautonomous Uribo2 element from the target vector construct but that for the Kobuta ORF did not. The present results support our viewpoint that some Uribo2 members are naturally active autonomous transposons, whereas Kobuta members may be domesticated by hosts.

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Expanding the Diversity of the IS630-Tc1-mariner Superfamily: Discovery of a Unique DD37E Transposon and Reclassification of the DD37D and DD39D Transposons

Genetics ◽

10.1093/genetics/159.3.1103 ◽

2001 ◽

Vol 159 (3) ◽

pp. 1103-1115 ◽

Cited By ~ 1

Author(s):

Hongguang Shao ◽

Zhijian Tu

Keyword(s):

Phylogenetic Analyses ◽

Mosquito Species ◽

Open Reading Frames ◽

Inverted Repeats ◽

Sequence Comparisons ◽

Wide Range ◽

Multiple Copies ◽

Catalytic Motif ◽

Open The Doors ◽

Reading Frames

Abstract A novel transposon named ITmD37E was discovered in a wide range of mosquito species. Sequence analysis of multiple copies in three Aedes species showed similar terminal inverted repeats and common putative TA target site duplications. The ITmD37E transposases contain a conserved DD37E catalytic motif, which is unique among reported transposons of the IS630-Tc1-mariner superfamily. Sequence comparisons and phylogenetic analyses suggest that ITmD37E forms a novel family distinct from the widely distributed Tc1 (DD34E), mariner (DD34D), and pogo (DDxD) families in the IS630-Tc1-mariner superfamily. The inclusion in the phylogenetic analysis of recently reported transposons and transposons uncovered in our database survey provided revisions to previous classifications and identified two additional families, ITmD37D and ITmD39D, which contain DD37D and DD39D motifs, respectively. The above expansion and reorganization may open the doors to the discovery of related transposons in a broad range of organisms and help illustrate the evolution and structure-function relationships among these distinct transposases in the IS630-Tc1-mariner superfamily. The presence of intact open reading frames and highly similar copies in some of the newly characterized transposons suggests recent transposition. Studies of these novel families may add to the limited repertoire of transgenesis and mutagenesis tools for a wide range of organisms, including the medically important mosquitoes.

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Complete Genome Sequence of the Naegleria fowleri (Strain LEE) Closed Circular Extrachromosomal Ribosomal DNA Element

Microbiology Resource Announcements ◽

10.1128/mra.01055-20 ◽

2020 ◽

Vol 9 (49) ◽

Author(s):

John C. Mullican ◽

Kristen M. Drescher ◽

Nora M. Chapman ◽

Steven Tracy

Keyword(s):

Ribosomal Dna ◽

Direct Repeat ◽

Repeated Sequence ◽

Single Copy ◽

Open Reading Frames ◽

Naegleria Fowleri ◽

Content Type ◽

Repeat Sequences ◽

Nægleria Fowleri ◽

Reading Frames

ABSTRACT The circular extrachromosomal ribosomal DNA (rDNA) element of Naegleria fowleri strain LEE was molecularly cloned and fully sequenced. The element comprises 15,786 bp and contains a single copy of the organism’s rDNA cistron. The nonribosomal sequence contains five potential open reading frames, two large direct repeat sequences, and numerous smaller repeated-sequence regions.

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Evolutionary History of Cucumber Mosaic Virus Deduced by Phylogenetic Analyses

Journal of Virology ◽

10.1128/jvi.76.7.3382-3387.2002 ◽

2002 ◽

Vol 76 (7) ◽

pp. 3382-3387 ◽

Cited By ~ 155

Author(s):

Marilyn J. Roossinck

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Virus Isolate ◽

Phylogenetic Analyses ◽

Open Reading Frames ◽

Broad Host Range ◽

Nontranslated Region ◽

History Of ◽

Evolutionary Success ◽

Reading Frames

ABSTRACT Cucumber mosaic virus (CMV) is an RNA plant virus with a tripartite genome and an extremely broad host range. Previous evolutionary analyses with the coat protein (CP) and 5′ nontranslated region (NTR) of RNA 3 suggested subdivision of the virus into three groups, subgroups IA, IB, and II. In this study 15 strains of CMV whose nucleotide sequences have been determined were used for a complete phylogenetic analysis of the virus. The trees estimated for open reading frames (ORFs) located on the different RNAs were not congruent and did not completely support the subgrouping indicated by the CP ORF, indicating that different RNAs had independent evolutionary histories. This is consistent with a reassortment mechanism playing an important role in the evolution of the virus. The evolutionary trees of the 1a and 3a ORFs were more compact and displayed more branching than did those of the 2a and CP ORFs. This may reflect more rigid host-interactive constraints exerted on the 1a and 3a ORFs. In addition, analysis of the 3′ NTR that is conserved among all RNAs indicated that evolutionary constraints on this region are specific to the RNA component rather than the virus isolate. This indicates that functions other than replication are encoded in the 3′ NTR. Reassortment may have led to the genetic diversity found among CMV strains and contributed to its enormous evolutionary success.

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Discovery of a new family of amphibians from northeast India with ancient links to Africa

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.0150 ◽

2012 ◽

Vol 279 (1737) ◽

pp. 2396-2401 ◽

Cited By ~ 59

Author(s):

Rachunliu G. Kamei ◽

Diego San Mauro ◽

David J. Gower ◽

Ines Van Bocxlaer ◽

Emma Sherratt ◽

...

Keyword(s):

Dna Sequences ◽

Nuclear Dna ◽

Phylogenetic Analyses ◽

Sister Group ◽

Northeast India ◽

Sister Group Relationship ◽

New Family ◽

Ancient Lineage ◽

Molecular Phylogenetic ◽

Threatened Habitats

The limbless, primarily soil-dwelling and tropical caecilian amphibians (Gymnophiona) comprise the least known order of tetrapods. On the basis of unprecedented extensive fieldwork, we report the discovery of a previously overlooked, ancient lineage and radiation of caecilians from threatened habitats in the underexplored states of northeast India. Molecular phylogenetic analyses of mitogenomic and nuclear DNA sequences, and comparative cranial anatomy indicate an unexpected sister-group relationship with the exclusively African family Herpelidae. Relaxed molecular clock analyses indicate that these lineages diverged in the Early Cretaceous, about 140 Ma. The discovery adds a major branch to the amphibian tree of life and sheds light on both the evolution and biogeography of caecilians and the biotic history of northeast India—an area generally interpreted as a gateway between biodiversity hotspots rather than a distinct biogeographic unit with its own ancient endemics. Because of its distinctive morphology, inferred age and phylogenetic relationships, we recognize the newly discovered caecilian radiation as a new family of modern amphibians.

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Genomically Intact Endogenous Feline Leukemia Viruses of Recent Origin

Journal of Virology ◽

10.1128/jvi.78.8.4370-4375.2004 ◽

2004 ◽

Vol 78 (8) ◽

pp. 4370-4375 ◽

Cited By ~ 45

Author(s):

Alfred L. Roca ◽

Jill Pecon-Slattery ◽

Stephen J. O'Brien

Keyword(s):

Long Terminal Repeat ◽

Related Species ◽

Germ Line ◽

Open Reading Frames ◽

Domestic Cats ◽

Repeat Sequences ◽

Recent Origin ◽

Leukemia Viruses ◽

Feline Leukemia Viruses ◽

Reading Frames

ABSTRACT We isolated and sequenced two complete endogenous feline leukemia viruses (enFeLVs), designated enFeLV-AGTT and enFeLV-GGAG. In enFeLV-AGTT, the open reading frames are reminiscent of a functioning FeLV genome, and the 5′ and 3′ long terminal repeat sequences are identical. Neither endogenous provirus is genetically fixed in cats but polymorphic, with 8.9 and 15.2% prevalence for enFeLV-AGTT and enFeLV-GGAG, respectively, among a survey of domestic cats. Neither provirus was found in the genomes of related species of the Felis genus, previously shown to harbor enFeLVs. The absence of mutational divergence, polymorphic incidence in cats, and absence in related species suggest that these enFeLVs may have entered the germ line more recently than previously believed, perhaps coincident with domestication, and reopens the question of whether some enFeLVs might be replication competent.

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Cloning and Analysis of the Telomere and Terminal Inverted Repeat of the Linear Chromosome of Streptomyces griseus

Journal of Bacteriology ◽

10.1128/jb.184.12.3411-3415.2002 ◽

2002 ◽

Vol 184 (12) ◽

pp. 3411-3415 ◽

Cited By ~ 34

Author(s):

Kohei Goshi ◽

Tetsuya Uchida ◽

Alexander Lezhava ◽

Masayuki Yamasaki ◽

Keiichiro Hiratsu ◽

...

Keyword(s):

Inverted Repeat ◽

Streptomyces Griseus ◽

Open Reading Frames ◽

Terminal Inverted Repeat ◽

Loop Structure ◽

Hairpin Loop ◽

Cloning And Sequencing ◽

Linear Chromosome ◽

Palindromic Sequences ◽

Reading Frames

ABSTRACT Cloning and sequencing of the telomere of Streptomyces griseus revealed five palindromic sequences in the terminal 116 nucleotides, all of which can make a hairpin loop structure. However, the end sequence cannot form the foldback secondary structure that is common in Streptomyces telomeres and is suggested to be necessary for terminal replication. Both inside ends of the terminal inverted repeat (TIR) were also cloned and sequenced. The results confirmed the size of the TIR to be 24 kb and identified two almost identical open reading frames that might have been involved in the formation of the TIR.

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Sixty years from the first disease description, a novel badnavirus associated with chestnut mosaic disease

Phytopathology ◽

10.1094/phyto-09-20-0420-r ◽

2020 ◽

Author(s):

Armelle Marais ◽

Sergio Murolo ◽

Chantal Faure ◽

Yoann Brans ◽

Clement Larue ◽

...

Keyword(s):

High Throughput Sequencing ◽

Molecular Detection ◽

Phylogenetic Analyses ◽

Epidemiological Studies ◽

Mosaic Disease ◽

Open Reading Frames ◽

Sequence Comparisons ◽

High Incidence ◽

The Usa ◽

Reading Frames

Although the chestnut mosaic disease (ChMD) was described several decades ago, its etiology is still not elucidated. Here, using classical approaches in combination with high throughput sequencing (HTS) techniques, we identify a novel Badnavirus that is a strong etiological candidate for ChMD. Two disease sources from Italy and France were submitted to HTS-based viral indexing. Total RNAs were extracted, ribodepleted and sequenced on an Illumina NextSeq500 (2x150 or 2x 75 nt). In each source, we identified a single contig of about 7.2 kilobases that corresponds to a complete circular viral genome and shares homologies with various badnaviruses. The genomes of the two isolates have an average nucleotide identity of 90.5% with a typical badnaviral genome organization comprising three open reading frames. Phylogenetic analyses and sequence comparisons show that this virus is a novel species for which we propose the name Chestnut mosaic virus (ChMV). Using a newly developed molecular detection test, we systematically detected the virus in symptomatic graft-inoculated indicator plants (chestnut and American oak), as well in chestnut trees presenting typical ChMD symptoms in the field (100% and 87% in France and Italy surveys, respectively). Datamining of publicly available chestnut SRA transcriptomic data allowed the reconstruction of two additional complete ChMV genomes from two Castanea mollissima sources from the USA, as well as ChMV detection in C. dentata from the USA. Preliminary epidemiological studies, performed in France and in Central Eastern Italy, showed that ChMV has a high incidence in some commercial orchards, with a low within-orchard genetic diversity.

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A study of molecular sequences, sexuality, and morphological variation in Plagiomnium carolinianum, P. maximoviczii, and P. rhynchophorum (Bryophyta, Mniaceae)

Phytotaxa ◽

10.11646/phytotaxa.375.1.4 ◽

2018 ◽

Vol 375 (1) ◽

pp. 81

Author(s):

YAN-JUN YI ◽

ZHEN-WEI SUN ◽

SI HE ◽

MAMTIMIN SULAYMAN

Keyword(s):

Phylogenetic Analyses ◽

Single Species ◽

Molecular Study ◽

Geographic Range ◽

Similar Species ◽

Monophyletic Clade ◽

Closely Related Species ◽

Molecular Phylogenetic ◽

Different Populations ◽

Rps4 Gene

Morphologically, recognition of the genus Plagiomnium may be relatively easy. Yet identifications of closely related species have met great difficulties. The contemporary species delimitations of P. carolinianum, P. maximoviczii, and P. rhynchophorum largely based on sexuality as the sole distinction have not been satisfactory. As shown from literature, character variations among these three taxa were continuous and intergraded within or among different populations throughout a wide geographic range. No gametophytic characters could be reliably used to distinguish them from each other. Molecular phylogenetic analyses using ITS2 and rps4 gene were undertaken to resolve delineations for these three morphologically similar species. The results suggest that they form a well support monophyletic clade, which can be defined as representing one single species with two subspecies, i.e. P. rhynchophorum subsp. maximoviczii and P. rhynchophorum subsp. rhynchophorum. The present molecular study supports the treatment of P. carolinianum as synonym of P. rhynchophorum as purposed previously by Koponen based on morphology.

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Description of Tottonophyes enigmatica gen. nov., sp. nov. (Hydrozoa, Siphonophora, Calycophorae), with a reappraisal of the function and homology of nectophoral canals

Zootaxa ◽

10.11646/zootaxa.4415.3.3 ◽

2018 ◽

Vol 4415 (3) ◽

pp. 452 ◽

Cited By ~ 1

Author(s):

P. R. PUGH ◽

C.W. DUNN ◽

S.H.D. HADDOCK

Keyword(s):

New Species ◽

Phylogenetic Analyses ◽

Sister Group ◽

The Other ◽

Phylogenetic Position ◽

Unique Combination ◽

New Family ◽

Molecular Phylogenetic ◽

Distinct Morphology ◽

A New Species

A new species of calycophoran siphonophore, Tottonophyes enigmatica gen. nov, sp. nov., is described. It has a unique combination of traits, some shared with prayomorphs (including two rounded nectophores) and some with clausophyid diphyomorphs (the nectophores are dissimilar, with one slightly larger and slightly to the anterior of the other, and both possess a somatocyst). Molecular phylogenetic analyses indicate that the new species is the sister group to all other diphyomorphs. A new family, Tottonophyidae, is established for it. Its phylogenetic position and distinct morphology help clarify diphyomorph evolution. The function and homology of the nectophoral canals and somatocyst is also re-examined and further clarification is given to their nomenclature.

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A Chemogenomic Screening of Sulfanilamide-Hypersensitive Saccharomyces cerevisiae Mutants Uncovers ABZ2, the Gene Encoding a Fungal Aminodeoxychorismate Lyase

Eukaryotic Cell ◽

10.1128/ec.00266-07 ◽

2007 ◽

Vol 6 (11) ◽

pp. 2102-2111 ◽

Cited By ~ 21

Author(s):

Javier Botet ◽

Laura Mateos ◽

José L. Revuelta ◽

María A. Santos

Keyword(s):

Large Scale ◽

Phylogenetic Analyses ◽

Open Reading Frames ◽

Gene Encoding ◽

Cellular Processes ◽

Founder Member ◽

Yeast Genes ◽

Vacuole Biogenesis ◽

Reading Frames

ABSTRACT Large-scale phenotypic analyses have proved to be useful strategies in providing functional clues about the uncharacterized yeast genes. We used here a chemogenomic profiling of yeast deletion collections to identify the core of cellular processes challenged by treatment with the p-aminobenzoate/folate antimetabolite sulfanilamide. In addition to sulfanilamide-hypersensitive mutants whose deleted genes can be categorized into a number of groups, including one-carbon related metabolism, vacuole biogenesis and vesicular transport, DNA metabolic and cell cycle processes, and lipid and amino acid metabolism, two uncharacterized open reading frames (YHI9 and YMR289w) were also identified. A detailed characterization of YMR289w revealed that this gene was required for growth in media lacking p-aminobenzoic or folic acid and encoded a 4-amino-4-deoxychorismate lyase, which is the last of the three enzymatic activities required for p-aminobenzoic acid biosynthesis. In light of these results, YMR289w was designated ABZ2, in accordance with the accepted nomenclature. ABZ2 was able to rescue the p-aminobenzoate auxotrophy of an Escherichia coli pabC mutant, thus demonstrating that ABZ2 and pabC are functional homologues. Phylogenetic analyses revealed that Abz2p is the founder member of a new group of fungal 4-amino-4-deoxychorismate lyases that have no significant homology to its bacterial or plant counterparts. Abz2p appeared to form homodimers and dimerization was indispensable for its catalytic activity.

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