The complete mitochondrial genome of the Bass yabby Trypaea australiensis was obtained from a partial genome scan using the MiSeq sequencing system. The T. australiensis mitogenome is 16,821 bp in length (70.25% A + T content) made up of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs and a putative 1977 bp non-coding AT-rich region. This Trypaea mitogenome sequence is the 5th for the family Callianassidae and represents a new gene order for the Decapoda involving protein-coding, rRNA and tRNA genes and the control region.
The complete genome sequence of the ALL-03 strain of rat cytomegalovirus (RCMV) has been determined. The RCMV genome has a length of 197,958 bp and is arranged as a single unique sequence flanked by 504-bp terminal direct repeats. This strain is closely related to the English strain of RCMV in terms of genetic arrangement but differs slightly in size.
The mitochondrial genome sequence of the Australian crayfish, Euastacus yarraensis, is documented and compared with other Australian crayfish genera. Euastacus yarraensis has a mitogenome of 15,548 base pairs consisting of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a non-coding AT-rich region. The base composition of E. yarraensis mitogenome is 32.39% for T, 22.45% for C, 34.43% for A, and 10.73% for G, with an AT bias of 66.82%. The mitogenome gene order conforms to what is considered the primitive arrangement for parastacid crayfish.
The complete mitochondrial genome of the enigmatic freshwater crayfish Engaeus lyelli was sequenced using the MiSeq Personal Sequencer (Illumina, San Diego, CA). The mitogenome has 16,027 bp consisting of 13 protein-coding genes, 2 ribosomal subunit genes, 23 transfer RNAs, and a non-coding AT-rich region. The base composition of E. lyelli is 29.01% for T, 27.13% for C, 31.43% for A, and 12.44% for G, with an AT bias of 60.44%. The species has the distinctive gene order characteristic of parastacid crayfish with the exception of some minor rearrangements involving the tRNA genes.
Two mitogenomes of long-tailed giant rat, Leopoldamys sabanus (Thomas, 1887), which belongs to the family Muridae were sequenced and assembled in this study. Both mitogenomes have a length of 15,973 bp and encode 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes and one control region. The circular molecule of L. sabanus has a typical vertebrate gene arrangement. Phylogenetic and BLASTn analysis using 10 Leopoldamys species mitogenomes revealed sequence variation occurred within species from different time zones. Along with the taxonomic issues, this suggests a landscape change might influence genetic connectivity.
The relative viabilities of homozygous and heterozygous karyotypes were measured by making crosses between strains ofD. ananassae homozygous for ST or inverted gene orders in the second and third chromosomes. The strains utilized during the present study originated from widely separated localities in India, Kuala Lumpur and Kota Kinabaru, Malaysia and Chian Mai, Thailand. The presence of heterosis in many interpopulation crosses is evident from the results which show that the inversion heterozygotes formed by chromosomes coming from distant populations exhibit heterosis. On the other hand, heterosis is absent in two intrapopulation crosses. Thus the present results provide evidence that heterozygosis for many genes and gene complexes does produce high fitness without previous selectional coadaptation.
The complete mitochondrial genome plays an important role in the research on phylogenetic relationship. Here, we reported the first complete mitochondrial genome sequence of Varuna yui Hwang & Takeda, 1986 (Varunidae). The complete mtDNA (15,915 bp in length) consisted of 13 protein-coding genes, 22 tRNAs, two rRNA genes, and a control region. The gene arrangement was identical to those observed in the Varunidae species. The phylogenetic analysis suggested that V. yui had close relationship with other Varunidae species (Helicetient sinensis, Eriocher sinesis, etc.). The newly described genome may facilitate further comparative mitogenomic analysis within Varunidae species.
In this study, we sequenced and analyzed the whole mitochondrial genome of Metopograpsus frontalis Miers, 1880 (Decapoda, Grapsidae). The circular genome is 15,587 bp in length, consisting of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, as well as a control region. Both atp8/atp6 and nad4L/nad4 share 7 nucleotides in their adjacent overlapping region, which is identical to those observed in other Grapsidae crabs. The genome composition and gene order follow a classic crab-type arrangement regulation. The phylogenetic analysis suggested that Grapsidae crabs formed a solid monophyletic group. The newly described mitochondrial genome may provide genetic marker for studies on phylogeny of the grapsid crabs.
The mitochondrial genome sequence of the purple mottled shore crab, Cyclograpsus granulosus, is documented (GenBank accession number: LN624373), which makes it the third for genera of the superfamily Grapsoidea. Cyclograpsus granulosus has a mitogenome of 16,300 bp consisting of 13 protein-coding genes, two ribosomal subunit genes, 22 transfer RNAs and a non-coding AT-rich region. The base composition of the C. granulosus mitogenome is 36.15% for T, 19.54% for C, 33.14% for A and 11.17% for G, with an AT bias of 69.29%. The mitogenome gene order is atypical for the brachyuran crabs, but is identical to species of the genus Eriocheir from the same family.
The mitochondrial genome sequence of the porcellanid crab, Petrolisthes haswelli is provided, making it the second for the family Porcellanidae and the third for the superfamily Galatheoidea. Petrolisthes haswelli has a mitogenome of 15,348 bp consisting of 13 protein-coding genes, two ribosomal subunit genes, 22 transfer RNAs and a non-coding AT-rich region. The base composition of the P. haswelli mitogenome is 35.66% for T, 18.65% for C, 34.35% for A and 11.34% for G, with an AT bias of 70.01%. The mitogenome gene order is identical to the mitogenome of Neopetrolisthes maculatus, the only other species of the family with a sequenced mitogenome.
The complete mitochondrial genome of the hermit crab Clibanarius infraspinatus was recovered by genome skimming using Next-Gen sequencing. The Clibanarius infraspinatus mitogenome has 16,504 base pairs (67.94% A + T content) made up of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs and a putative 1500 bp non-coding AT-rich region. The Clibanarius infraspinatus mitogenome sequence is the first for the family Diogenidae and the second for the superfamily Paguroidea and exhibits a translocation of the ND3 gene not previously reported for the Decapoda.
The infraorder Anomura consists of a morphologically and ecologically heterogeneous group of decapod crustaceans, and has attracted interest from taxonomists for decades attempting to find some order out of the seemingly chaotic diversity within the group. Species-level diversity within the Anomura runs the gamut from the "hairy" spindly-legged yeti crab found in deep-sea hydrothermal vent environments to the largest known terrestrial invertebrate, the robust coconut or robber crab. Owing to a well-developed capacity for parallel evolution, as evidenced by the occurrence of multiple independent carcinization events, Anomura has long tested the patience and skill of both taxonomists attempting to find order, and phylogeneticists trying to establish stable hypotheses of evolutionary inter-relationships. In this study, we performed genome skimming to recover the mitogenome sequences of 12 anomuran species including the world's largest extant invertebrate, the robber crab (Birgus latro), thereby over doubling these resources for this group, together with 8 new brachyuran mitogenomes. Maximum-likelihood (ML) and Bayesian-inferred (BI) phylogenetic reconstructions based on amino acid sequences from mitogenome protein-coding genes provided strong support for the monophyly of the Anomura and Brachyura and their sister relationship, consistent with previous studies. The majority of relationships within families were supported and were largely consistent with current taxonomic classifications, whereas many relationships at higher taxonomic levels were unresolved. Nevertheless, we have strong support for a polyphyletic Paguroidea and recovered a well-supported clade of a subset of paguroids (Diogenidae + Coenobitidae) basal to all other anomurans, though this requires further testing with greater taxonomic sampling. We also introduce a new feature to the MitoPhAST bioinformatics pipeline (https://github.com/mht85/MitoPhAST) that enables the extraction of mitochondrial gene order (MGO) information directly from GenBank files and clusters groups based on common MGOs. Using this tool, we compared MGOs across the Anomura and Brachyura, identifying Anomura as a taxonomic "hot spot" with high variability in MGOs among congeneric species from multiple families while noting the broad association of highly-rearranged MGOs with several anomuran lineages inhabiting extreme niches. We also demonstrate the value of MGOs as a source of novel synapomorphies for independently reinforcing tree-based relationships and for shedding light on relationships among challenging groups such as the Aegloidea and Lomisoidea that were unresolved in phylogenetic reconstructions. Overall, this study contributes a substantial amount of new genetic material for Anomura and attempts to further resolve anomuran evolutionary relationships where possible based on a combination of sequence and MGO information. The new feature in MitoPhAST adds to the relatively limited number of bioinformatics tools available for MGO analyses, which can be utilized widely across animal groups.
The mitochondrial genome of the rock pool prawn (Palaemon serenus), is sequenced, making it the third for genera of the family Palaemonidae and the first for the genus Palaemon. The mitogenome is 15,967 base pairs in length and comprises 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs and a non-coding AT-rich region. The P. serenus mitogenome has an AT bias of 58.97% and a base composition of 29.79% for T, 24.14% for C, 29.18% for A, and 16.89% for G. The mitogenome gene order of P. serenus is identical to Exopalaemon carinicauda.
The mitochondrial genome sequence of the Morton Bay bug, Thenus orientalis, is documented, which makes it the second mitogenome for species of the family Scyllaridae and the ninth for members of the superfamily Palinuroidae. Thenus orientalis has a mitogenome of 16,826 base pairs consisting of 13 protein-coding genes, 2 ribosomal subunit genes, 23 transfer RNAs, and a non-coding AT-rich region. The base composition of the T. orientalis mitogenome is 31.31% for T, 23.77% for C, 31.05% for A, and 13.87% for G, with an AT bias of 62.36%. In addition to a duplicated trnS1 and several other tRNA gene rearrangements, the mitogenome gene order has novel protein coding gene order with the nad6 and cob genes translocated as a block to a location downstream of the nad3 gene.
The complete mitochondrial genome of the commercially important snout otter clam Lutraria rhynchaena was obtained from low-coverage shotgun sequencing data on the MiSeq platform. The L. rhynchaena mitogenome has 16,927 base pairs (69% A + T content) and made up of 12 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a 953 bp non-coding AT-rich region. This is the first mitogenome to be sequenced from the genus Lutraria, and the seventh to be reported for the family Mactridae.
Although it is possible to recover the complete mitogenome directly from shotgun sequencing data, currently reported methods and pipelines are still relatively time consuming and costly. Using a sample of the Australian freshwater crayfish Engaeus lengana, we demonstrate that it is possible to achieve three-day turnaround time (four hours hands-on time) from tissue sample to NCBI-ready submission file through the integration of MiSeq sequencing platform, Nextera sample preparation protocol, MITObim assembly algorithm and MITOS annotation pipeline.
The Pangasius sutchi is an important ornamental and economic fish in Southeast Asia e.g. Thailand, Malaysia and China. The complete mitochondrial genome sequence of P. sutchi has been sequenced, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes and a non-coding control region with the total length of 16,522 bp. The gene order and composition are similar to most of other vertebrates. Just like most other vertebrates, the bias of G and C was found in different region/genes statistics results. Most of the genes are encoded on heavy strand, except for eight tRNA and ND6 genes. The mitogenome sequence of P. sutchi would contribute to better understand population genetics, evolution of this lineage.
The cavity-nesting honeybee Apis nuluensis inhabits only the highlands of Mount Kinabalu of Sabah, Borneo Island. The mitochondrial genome is a circular molecule of approximately 1.6 kb that includes 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one AT-rich control region. The average AT content was 84.5%. The start codons ATC, ATG, and ATT were found in one, three, and nine genes, respectively, whereas the stop codon TAA was observed in all genes. The phylogenetic relationship, inferred using 13 PCGs, was consistent with that reported in previous studies that predicted a sister taxon relationship between A. nuluensis and A. cerana.
The main aim of our study was to explore the genome sequence of the inclusion body hepatitis associated Fowl adenovirus serotype 8b (FAdV-8b) UPM04217 and to study its genomic organisation. The nucleotide sequence of the whole genome of FAdV-8b UPM04217 was determined by using the 454 Pyrosequencing platform and the Sanger sequencing method. The complete genome was found to be 44,059 bp long with 57.9% G + C content and shared 97.5% genome identity with the reference FAdV-E genome (HG isolate). Interestingly, the genome analysis using ORF Finder, Glimmer3 and FGENESV predicted a total of 39 open reading frames (ORFs) compared to the FAdV-E HG that possessed 46 ORFs. Fourteen ORFs located within the central genomic region and 16 ORFs located within the left and right ends of the genome were assigned as being the high protein-coding regions. The fusion of the small ORFs at the right end terminal specifically in ORF22 and ORF33 could be the result of gene truncation in the FAdV-E HG. The frame shift mutation in ORF25 and other mutations in ORF13 and ORF17 might have lead to the emergence of genes that could have different functions. Besides, one of the minor capsid components, pVI, in FAdV-8b UPM04217 shared the highest similarity of 93% with that of FAdV-D, while only 47% similarity was found with FAdV-E. From the gene arrangement layout of the FAdV genome, FAdV-8b UPM04217 showed intermediate evolution between the FAdV-E HG and the FAdV-D although it was apparently more similar to the FAdV-E HG.
Using a new fossil-calibrated mitogenome-based approach, we identified macroevolutionary shifts in mitochondrial gene order among the freshwater mussels (Unionoidea). We show that the early Mesozoic divergence of the two Unionoidea clades, Margaritiferidae and Unionidae, was accompanied by a synchronous split in the gene arrangement in the female mitogenome (i.e., gene orders MF1 and UF1). Our results suggest that this macroevolutionary jump was completed within a relatively short time interval (95% HPD 201-226 Ma) that coincided with the Triassic-Jurassic mass extinction. Both gene orders have persisted within these clades for ~200 Ma. The monophyly of the so-called "problematic" Gonideinae taxa was supported by all the inferred phylogenies in this study using, for the first time, the M- and F-type mitogenomes either singly or combined. Within Gonideinae, two additional splits in the gene order (UF1 to UF2, UF2 to UF3) occurred in the Mesozoic and have persisted for ~150 and ~100 Ma, respectively. Finally, the mitogenomic results suggest ancient connections between freshwater basins of East Asia and Europe near the Cretaceous-Paleogene boundary, probably via a continuous paleo-river system or along the Tethys coastal line, which are well supported by at least three independent but almost synchronous divergence events.