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1.
The complete mitochondrial genome of the spinyhead croaker Collichthys lucidus was determined using long-PCR and primer walking methods. It is a circular molecule of 16,451 bp in length with a standard set of 22 tRNAs, 2 rRNAs, 13 protein-coding genes as well as a non-coding control region in the same order as those of the other bony fishes. C. lucidus mitogenome exhibited a clear strand-specific bias in nucleotide composition, as evidence by a GC- skew of the H-strand of −0.319. The strand-specific bias was also reflected in the codon usage of genes oriented in opposite directions. All tRNA genes except for tRNA Ser(AGY) harbored the typical cloverleaf secondary structures and possessed anticodons that matched the vertebrate mitochondrial genetic code. Contrary to the typical structure of control region consistig of TAS, central, and CSB domains, there were no central conserved blocks available in C. lucidus mitogenome. Despite extensive studies based on both morphology and molecules, phylogenetic position of C. lucidus with Sciaenidae is still controversial. Our phylogenetic results provided more evidence to support previous morphological studies and consistently placed C. lucidus as a sister taxon to Collichthys niveatus, with both of these taxa forming the monophyletic Collichthys.  相似文献   

2.
The complete mitochondrial genome (mitogenome) sequence of the silver croaker, Argyrosomus argentatus, was obtained by using LA-PCR and sequencing. The mitogenome is 16485 bp in length, consists of 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a non-coding control region like those found in other vertebrates, with the gene order similar to that of typical teleosts. Most of the genes of A. argentatus were encoded on the H-strand, while the ND6 and eight tRNA (Gln, Ala, Asn, Cys, Tyr, Ser (UCN), Glu and Pro) genes were encoded on the L-strand. The reading frames of two pairs of genes overlapped: ATPase8 and 6 and ND4L and ND4 by ten and seven nucleotides, respectively. The origin of L-strand replication in A. argentatus was in a cluster of five tRNA genes (WANCY) and was 46 nucleotides in length. The conserved motif (5′-GCGGG-3′) was found at the base of the stem within the tRNACys gene. Within the control region, we identified all of the conserved motifs except for CSB-F.  相似文献   

3.
The complete mitochondrial genome (mtDNA) of snow leopard Panthera uncia was obtained by using the polymerase chain reaction (PCR) technique based on the PCR fragments of 30 primers we designed. The entire mtDNA sequence was 16 773 base pairs (bp) in length, and the base composition was: A—5,357 bp (31.9%); C—4,444 bp (26.5%); G—2,428 bp (14.5%); T—4,544 bp (27.1%). The structural characteristics [0] of the P. uncia mitochondrial genome were highly similar to these of Felis catus, Acinonyx jubatus, Neofelis nebulosa and other mammals. However, we found several distinctive features of the mitochondrial genome of Panthera unica. First, the termination codon of COIII was TAA, which differed from those of F. catus, A. jubatus and N. nebulosa. Second, tRNASer (AGY), which lacked the ‘‘DHU’’ arm, could not be folded into the typical cloverleaf-shaped structure. Third, in the control region, a long repetitive sequence in RS-2 (32 bp) region was found with 2 repeats while one short repetitive segment (9 bp) was found with 15 repeats in the RS-3 region. We performed phylogenetic analysis based on a 3 816 bp concatenated sequence of 12S rRNA, 16S rRNA, ND2, ND4, ND5, Cyt b and ATP8 for P. uncia and other related species, the result indicated that P. uncia and P. leo were the sister species, which was different from the previous findings.  相似文献   

4.
Freshwater gobies Rhinogobius cliffordpopei and R. giurinus are invasive species with particular concern because they have become dominant and were fierce competitors in the invaded areas in Yunnan-Guizhou Plateau (southwest of China). Information about genetic characteristics of R. giurinus have been published, but there were still no relevant reports about R. cliffordpopei. In present study, the complete mitochondrial genome of R. cliffordpopei was determined, which was 16,511 bp in length with A?+?T content of 51.1%, consisting of 13 protein-coding genes, 22 tRNAs, 2 ribosomal RNAs, and a control region. The gene composition and the structural arrangement of the R. cliffordpopei complete mtDNA were identical to most of other teleosts. Phylogenetic analyses placed R. cliffordpopei in a well-supported monophyletic cluster with other Rhinogobius fish. But the phylogenetic relationship between genus Rhinogobius and Tridentiger remained to be resolved.  相似文献   

5.
Chloroplast genome sequences are very useful for species identification and phylogenetics. Chuanminshen (Chuanminshen violaceum Sheh et Shan) is an important traditional Chinese medicinal plant, for which the phylogenetic position is still controversial. In this study, the complete chloroplast genome of Chuanminshen violaceum Sheh et Shan was determined. The total size of Chuanminshen chloroplast genome was 154,529 bp with 37.8% GC content. It has the typical quadripartite structure, a large single copy (17,800 bp) and a small single copy (84,171 bp) and a pair of inverted repeats (26,279 bp). The whole genome harbors 132 genes, which includes 85 protein coding genes, 37 tRNA genes, eight rRNA genes, and two pseudogenes. Thirty-nine SSR loci, 32 tandem repeats and 49 dispersed repeats were found. Phylogenetic analyses results with the help of MEGA showed a new insight for the Chuanminshen phylogenetic relationship with the reported chloroplast genomes in Apiales plants.  相似文献   

6.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

7.
Pseudoroegneria libanotica is an important herbage diploid species possessing the St genome. The St genome participates in the formation of nine perennial genera in Triticeae (Poaceae). The whole chloroplast (cp) genome of P. libanotica is 135 026 bp in length. The typical quadripartite structure consists of one large single copy of 80 634 bp, one small single copy of 12 766 bp and a pair of inverted regions (20 813 bp each). The cp genome contains 76 coding genes, four ribosomal RNA and 30 transfer RNA genes. Comparative sequence analysis suggested that: 1) the 737 bp deletion in the cp of P. libanotica was specific in Triticeae species and might transfer into its nuclear genome; 2) hot-spot regions, indels in intergenic regions and protein coding sequences mainly led to the length variation in Triticeae; 3) highly divergence regions combined with negative selection in rpl2, rps12, ccsA, rps8, ndhH, petD, ndhK, psbM, rps3, rps18, and ndhA were identified as effective molecular markers and could be considered in future phylogenetic studies of Triticeae species; and 4) ycf3 gene with rich cpSSRs was suitable for phylogeny analysis or could be used for DNA barcoding at low taxonomic levels. The cpSSRs distribution in the coding regions of diploid Triticeae species was shown for the first time and provided a valuable source for developing primers to study specific simple sequence repeat loci.  相似文献   

8.
Vanessa indica is a small butterfly lacking historical molecular and biological research. Vanessa indica belongs to the family Nymphalidae (Lepidoptera: Papilionoidea), which is the largest group of butterflies and are nearly ubiquitous. However, after more than a century of taxonomic and molecular studies, there is no consensus for family classification, and the phylogenetic relationships within Nymphalidae are controversial. The first objective was to sequence and characterize the complete mitochondrial genome of V. indica. The most important objective was to completely reconstruct the phylogenetic relationships for family members within Nymphalidae. The mitochondrial genomic DNA (mtDNA) of V. indica was extracted and amplified by polymerase chain reaction. The complete mitochondrial sequence was annotated and characterized by analyzing sequences with SeqMan program. The phylogenetic analyses were conducted on thirteen protein coding genes (PCGs) in 95 mtDNA of Nymphalidae downloaded from GenBank for reference using the maximum likelihood method and Bayesian inference to ensure the validity of the results. The complete mitogenome was a circular molecule with 15,191 bp consisting of 13 protein coding genes, two ribosomal RNA genes (16S rRNA and 12S rRNA), 22 transfer RNA (tRNA) genes, and an A?+?T-rich region (D-loop). The nucleotide composition of the genome was highly biased for A?+?T content, which accounts for 80.0% of the nucleotides. All the tRNAs have putative secondary structures that are characteristic of mitochondrial tRNAs, except tRNASer(AGN). All the PCGs started with ATN codons, except cytochrome c oxidase subunit 1 (COX1), which was found to start with an unusual CGA codon. Four genes were observed to have unusual codons: COX1 terminated with atypical TT and the other three genes terminated with a single T. The A?+?T rich region of 327 bp consisted of repetitive sequences, including a ATAGA motif, a 19-bp poly-T stretch, and two microsatellite-like regions (TA)8. The phylogenetic analyses consistently placed Biblidinae as a sister cluster to Heliconiinae and Calinaginae as a sister clade to Satyrinae. Moreover, the phylogenetic tree identified Libytheinae as a monophyletic group within Nymphalidae. The complete mitogenome of V. indica was 15,191 bp with mitochondrial characterizations common for lepidopteran species, which enriched the mitochondria data of Nymphalid species. And the phylogenetic analysis revealed different classifications and relationships than those previously described. Our results are significant because they would be useful in further understanding of the evolutionary biology of Nymphalidae.  相似文献   

9.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

10.
11.
The monotypic genus Damora (Nymphalidae, Heliconiinae) contains a single species, Damora sagana, which is widely distributed across southern China. Herein, its complete mitogenome was sequenced to further understand lepidopteran mitogenome characteristics, reconstruct the nymphalid family phylogeny, and infer the subdivision of Heliconiinae species. The circular mitogenome was 15,151 bp long, abundant in A and T, and comprised of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and one control region with a gene arrangement typical of lepidopteran mitogenomes. ATN codons initiated all PCGs, except cytochrome c oxidase subunit 1 (COX1), which was initiated by a CGA sequence as has been observed in other lepidopterans. Three PCGs (COX1, COX2 and ND4) employed a single T termination signal, whereas others had the typical complete termination codon (TAA). All tRNA genes were folded into the typical cloverleaf structure except for tRNA-Ser (AGN). The A+T-rich region included the conserved motif ‘ATAGA’ followed by a 17 bp poly-T stretch, which was also observed in tribe Argynnini mitogenomes. A phylogenetic tree was constructed via multiple methods using the 13 PCGs data of D. sagana and other available mitogenomes of nymphalid species. All three phylogenetic trees yielded the same topology. These results were consistent with those from previous studies of most major nymphalid groups, except those regarding tribe subdivision in certain subfamilies such as Argynnini + (Acraeini + Heliconiini) for Heliconiine. Furthermore, our analyses identified that the genus Cethosia was grouped with the genus Acraea composing the tribe Acraeini with strong support.  相似文献   

12.
The complete mitochondrial genome sequence of the marbled rockfish Sebastiscus marmoratus (Scorpaeniformes, Scorpaenidae) was determined and phylogenetic analysis was conducted to elucidate the evolutionary relationship of the marbled rockfish with other Sebastinae species. This mitochondrial genome, consisting of 17301 bp, is highly similar to that of most other vertebrates, containing the same gene order and an identical number of genes or regions, including 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and one putative control region. Most of the genes are encoded on the H-strand, while the ND6 and seven tRNA genes (for Gln, Ala, Asn, Tyr, Ser (UCA), Glu, and Pro) are encoded on the L-strand. The reading frame of two pairs of genes overlapped on the same strand (the ATPase 8 and 6 genes overlapped by ten nucleotides; ND4L and ND4 genes overlapped by seven nucleotides). The possibly nonfunctional light-strand replication origin folded into a typical stem-loop secondary structure and a conserved motif (5′-GCCGG-3′) was found at the base of the stem within the tRNACys gene. An extent termination-associated sequence (ETAS) and conserved sequence blocks (CSB) were identified in the control region, except for CSB-1; unusual long tandem repeats were found at the 3′ end of the control region. Phylogenetic analyses supported the view that Sebastinae comprises four genera (Sebastes, Hozukius, Helicolenus, and Sebastiscus).  相似文献   

13.
Cheng J  Ma GQ  Song N  Gao TX 《Gene》2012,491(2):210-223
The monophyly and phylogenetic relationships of Pseudosciaeniae have long been controversial. Here we describe the mitochondrial genome (mitogenome) sequence of Collichthys niveatus. It is a circular double-stranded DNA molecule of 16,450 base pairs (bp) in length with a standard set of 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), 13 protein-coding genes as well as a non-coding control region. The mitogenome of C. niveatus shared common features with those of other bony fishes in terms of gene arrangement, base composition, and tRNA structures. The C. niveatus mitogenome exhibited pronounced strand-specific asymmetry in nucleotide composition, which was also reflected in the codon usage of genes oriented in opposite directions. Contrary to the typical structure of the control region, the central conserved blocks (CSB-D, -E, and -F) could not be detected in C. niveatus mitogenome. Phylogenetic analysis based on whole mitogenome sequences provided strong support for the monophyly of Pseudosciaeniae, and sister-group relationships of C. niveatus + Collichthys lucidus and Larimichthys crocea + Larimichthys polyactis, which was consistent with the traditional taxonomy. Unexpected divergence was found in two C. niveatus mitogenomes and several hypotheses were proposed to explain this observation including misidentification and introgressive hybridization between C. niveatus and L. polyactis, and polyphyletic origin of C. niveatus. We considered species misidentification to be the main hypothesis. However, additional data is essential to test these proposed hypotheses.  相似文献   

14.
Passeriformes is the largest group within aves and the phylogenetic relationships between Passeriformes have caused major disagreement in ornithology. Particularly, the phylogenetic relationships between muscicapoidea and sylvioidea are complex, and their taxonomic boundaries have not been clearly defined. Our aim was to study the status of two bird species: Tarsiger cyanurus and Phoenicurus auroreus. Furthermore, we analyzed the phylogenetic relationships of Passeriformes. Complete mitochondrial DNA (mtDNA) sequences of both species were determined and the lengths were 16,803 (T. cyanurus) and 16,772 bp (P. auroreus), respectively. Thirteen protein-coding genes, 22 tRNA genes, two rRNA genes, and one control region were identified in these mtDNAs. The contents of A and T at the base compositions was significantly higher than the content of G and C, and this AT skew was positive, while the GC skew was negative. The monophyly of Passeriformes is divided into four major clades: Corvoidea, Sylvioidea, Passeroidea, and Musicicapoidea. Paridae should be separated from the superfamily Sylvioidea and placed within the superfamily Muscicapoidea. The family Muscicapidae and Corvida were paraphyly, while Carduelis and Emberiza were grouped as a sister taxon. The relationships between some species of the order passeriformes may remain difficult to resolve despite an effort to collect additional characters for phylogenetic analysis. Current research of avian phylogeny should focus on adding characters and taxa and use both effectively to obtain a better resolution for deeper and shallow nodes.  相似文献   

15.
Molecular markers derived from the complete chloroplast genome can provide effective tools for species identification and phylogenetic resolution. Complete chloroplast (cp) genome sequences of Capsicum species have been reported. We herein report the complete chloroplast genome sequence of Capsicum baccatum var. baccatum, a wild Capsicum species. The total length of the chloroplast genome is 157,145 bp with 37.7 % overall GC content. One pair of inverted repeats, 25,910 bp in length, was separated by a small single-copy region (17,974 bp) and large single-copy region (87,351 bp). This region contains 86 protein-coding genes, 30 tRNA genes, 4 rRNA genes, and 11 genes contain one or two introns. Pair-wise alignments of chloroplast genome were performed for genome-wide comparison. Analysis revealed a total of 134 simple sequence repeat (SSR) motifs and 282 insertions or deletions variants in the C. baccatum var. baccatum cp genome. The types and abundances of repeat units in Capsicum species were relatively conserved, and these loci could be used in future studies to investigate and conserve the genetic diversity of the Capsicum species.  相似文献   

16.
17.
He CB  Wang J  Gao XG  Song WT  Li HJ  Li YF  Liu WD  Su H 《Molecular biology reports》2011,38(5):3401-3409
Veneridae is a diverse, commercially important, and cosmopolitan family. Here we present the complete mitochondrial genome of the hard clam Meretrix meretrix (Bivalvia: Veneridae). The entire mitochondrial genome (mitogenome) sequence of M. meretrix is 19,826 bp in length, and contains 37 genes including 12 protein-coding genes, 2 ribosomal RNAs, and 23 tRNAs. All genes are encoded on the heavy strand. In contrast to the typical animal mitochondrial genome, it lacks the protein-coding gene ATP8, and has only one copy of the tRNASer gene, but three duplications of the tRNAGln, which is the first report among the present molluscan mtDNAs. We observed that the gene arrangement between M. meretrix and M. petechialis is same except one more tRNAGln gene in M. meretrix., and the sequence similarity is as high as 99%, indicating that M. petechialis and M. meretrix could be treated as a junior synonym of M. meretrix. Maximum Likelihood and Bayeslan analysis of 12 concatenated protein-coding amino acid sequences place the Unionidae as a sister group to other bivalves, which reflects the general opinion that the Unionidae deverged very early in Bivalvia evolution.  相似文献   

18.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

19.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

20.
The complete mitochondrial genome 15,650 bp in size of the Deracantha onos has been determined. The gene content, base composition and codon usage of D. onos are coincident to typical hexapods mitochondrial genomes. Genes arrangement of D. onos is identical to Gryllotalpa orientalis, Ruspolia dubia and Anabrus simplex, in that the relative locations of tRNALys and tRNAAsp was different to that of Locusta migratoria. All tRNAs could be folded into the typical cloverleaf secondary structure, excluding tRNASer(AGN) which forms another structure according to the Steinberg–Cedergren tertiary structure. Sequence analysis of the A + T-rich region with Dot-plot did not find any conspicuous repeat clusters. Two poly-thymine (poly-T) nucleotide stretches of 20 bp and 11 bp in size, which may involved in the recognition of replication origin, were found on the H-strand and L-strand in the A + T-rich region of the D. onos mitogenome, respectively. One open reading frame (ORF) 87 amino acids in size was found on the H-strand, but Protein Blast searches analysis indicated that it was a nonfunctional ORF.  相似文献   

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