Complete mitochondrial genome of the Amur stickleback Pungitius sinensis (Gasterosteiformes, Gasterosteidae)

The complete mitochondrial genome was sequenced from the Amur stickleback Pungitius sinensis. The genome sequence was 16,581 bp in size, and the gene order and contents were identical with those of previously reported fish mitochondrial genomes. Of 13 protein-coding genes (PCGs), four genes (ND2, CO2, ND4, Cytb) had incomplete stop codons. The base composition of P. sinensis showed anti-G bias (9.53%) on the third position of PCGs.     

Hybrid male sterility between the fresh- and brackish-water types of ninespine stickleback Pungitius pungitius (Pisces, Gasterosteidae)

Two ecologically distinct forms, fresh- and brackish-water types, of ninespine stickleback co-exist in several freshwater systems on the coast of eastern Hokkaido. Recent genetic analyses of 13 allozyme loci revealed genetic separation between the two types even though their spawning grounds were in close proximity. On the other hand, there is only a small difference in mitochondrial DNA (mtDNA) sequence between the two types suggesting that they diverged quite recently or that mtDNA introgression occurred between them. To test for postzygotic reproductive isolating mechanisms and hybrid mediated gene flow, we examined the viability and reproductive performance of reciprocal F1 hybrids. The hybrids grew to the adult size normally and both sexes expressed secondary sexual characters in the reciprocal crosses. The female hybrids were reciprocally fertile, while the male hybrids were reciprocally sterile. Histological and flow-cytometric analyses of the hybrid testis revealed that the sterility pattern was classified as 'gametic sterility,' with gonads of normal size but abnormal spermatogenesis. To our knowledge, the present finding is a novel example of one sex hybrid sterility in the stickleback family (Gasterosteidae).     

Lactate dehydrogenase isozymes and allozymes of the nine-spined stickleback Pungitius pungitius (L.) (Osteichthyes: Gasterosteidae)

Zymograms indicate the existence of three loci coding for lactate dehydrogenase in the nine-spined stickleback Pungitius pungitius. The skeletal muscle locus is polymorphic for two codominant alleles: Ldh-A(100). and Ldh-A(140). Differences in allele frequencies among nine samples, obtained from eight geographically isolated populations, proved not significant in 28/36 pairwise comparisons. The frequency of Ldh-A(100) varied from 0.426 to 0.715. Significant differences in apparent Km (pyruvate) values were found among the LDH-A allozymes suggesting a functional basis for the selective maintenance of this polymorphism.     

Parasites of the nine-spined stickleback Pungitius pungitius (L)

Eleven species of parasite are reported from the nine-spined stickleback Pungitius pungitius (L). Nine of these, namely, Trichodina domerguei, T. tenuidens, Vorticella sp., Epistylis?, Diplostomum spathaceum, Cryptocotyle lingua, Proteocephalus filicollis, Schistocephalus solidus and glochidia of Anodonta cygnea, are new host records for Great Britain. Gyrodactylus spp. and Thersitina gasterostei were also found.     

Karyotype differentiation between two stickleback species (Gasterosteidae)

The stickleback family (Gasterosteidae) of fish is less than 40 million years old, yet stickleback species have diverged in both diploid chromosome number (2n) and morphology. We used comparative fluorescence in situ hybridization (FISH) on 2 stickleback species, Gasterosteus aculeatus (2n = 42) and Apeltes quadracus (2n = 46), to ascertain the types of chromosome rearrangements that differentiate these species. The A. quadracus karyotype contains more acrocentric and telocentric chromosomes than the G. aculeatus karyotype. By using bacterial artificial chromosome probes from G. aculeatus in our FISH screen, we found that 6 pericentric inversions and 2 chromosome fusions/fissions are responsible for the greater number of acrocentric and telocentric chromosomes in A. quadracus. While most populations of G. aculeatus have an XX/XY sex chromosome system, A. quadracus has a ZZ/ZW sex chromosome system, as previously reported. However, we discovered that a population of A. quadracus from Connecticut lacks heteromorphic sex chromosomes, providing evidence for unexpected sex chromosome diversity in this species.     

Complete mitochondrial genome of Oxya chinensis （Orthoptera, Acridoidea）

The complete sequence of Oxya chinensis （0. chinensis） mitochondrial genome is reported here. It is 15,443 bp in length and contains 75.9% A＋T. The protein-coding genes have a similar A＋T content （75.2%）. The initiation codon of the cytochrome oxidase subunit I gene in the mitochondrial genome of O. chinensis appears to be ATC, instead of the tetranucleotides that have been reported in Locusta migratoria （L migratoria） mitochondrial genome. The sizes of the large and small ribosomal RNA genes are 1319 and 850 bp, respectively. The transfer RNA genes have been modeled and showed strong resemblance to the dipteran transfer RNAs, and all anticodons are identical to those of dipteran. The A＋T-rich region is 562 bp, shorter than that of other known Orthoptera insects. The six conserved domains were identified within the A＋T-rich region by comparing its sequence with those of other grasshoppers. The result of phylogenetic analysis based on the dataset containing 12 concatenated protein sequences confirms the close relation-ship of O. chinensis with L migratoria.     

Complete mitochondrial genome of Oxuderces dentatus (Perciformes, Gobioidei)

The complete mitochondrial genome (mitogenome) of Oxuderces dentatus was determined first. The genome was 17,116?bp in length and consisted of 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes, and 2 main non-coding regions [the control region (CR) and the origin of the light strand replication], the gene composition and order of which was similar to most other vertebrates. The overall base composition of the heavy strand was T 27.9%, C 26.8%, A 30.2%, and G 15.1%, with a slight A+T bias of 58.1%. In addition to the discrete and conserved sequence blocks, unusual long tandem repeat unit (three 150-bp tandem repeat units and an incomplete copy of 146?bp) was also detected within CR. This mitogenome sequence data would play an important role in population genetics and phylogenetic analysis of the Gobioidei.     

Complete mitochondrial genome of Liobagrus obesus (Siluriformes, Amblycipitidae)

Liobagrus obesus (Siluriformes, Amblycipitidae) is an endemic, endangered species in South Korea. Throughout this study, complete mitochondrial genome of L. obesus was sequenced, which is 16,506 bp in length. Its detail characteristics were described in this study.     

Complete mitochondrial genome of Trypauchen vagina (Perciformes, Gobioidei)

The complete mitochondrial genome of Trypauchen vagina was determined first. The genome is 16,686 bp in length and consists of 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes, and 2 main non-coding regions [the control region (CR) and the origin of the light strand replication], the gene composition and order of which was similar to most other vertebrates. The overall base composition of T. vagina is T 27.6%, C 27.6%, A 29.5%, and G 15.3%, with a slight A+T bias of 57.1%. In addition to the discrete and conserved sequence blocks, an incomplete tandem repeat unit is detected within the CR. This mitogenome sequence data would play an important role in population genetics and phylogenetic analysis of the Gobioidei.     

Parasite fauna of the amur sickleback Pungitius sinensis ( Gasterosteidae) from the Primor'e region

An ecological analysis of parasite fauna occurring in the Amur sickleback in different water basins of the Maritime Territory is carried out. Possible pathways of distribution of this fish within the Maritime Territory is discussed.     

State-Dependent Mate-Assessment and Mate-Selection Behavior in Female Threespine Sticklebacks (Gasterosteus aculeatus, Gasterosteiformes: Gasterosteidae)

Most investigations of mate-choice have focused on the outcomes of mate-choice (i.e. which mates are chosen), and thus we generally know very little about how mates are chosen (i.e. how mates are found, assessed, and selected). Mate-choice by females has been shown to be dependent on the state of the female, with females being less selective when limited by time or energy. This result could be caused by changes in female mate-assessment or mate-selection behavior. We examined whether manipulations of time and energy affected the mate-choice behavior of female threespine stickleback ( Gasterosteus aculeatus ). We found that female mate-choice behavior, when not divided into stages, was affected by both of the manipulations. This matches previous findings. When we divided female courtship behavior into six stages, we found that the two manipulations affected different portions of the mate-choice process. The holding-time manipulation changed female behavior at the beginning and end of the mate-choice process and the swimming manipulation changed female behavior only at the end of the mate-choice process. Neither of the manipulations significantly affected female behavior in the middle portion of the mate-choice process. Thus, the mate-choice process appears to be composed of multiple state-dependent decisions. We discuss how a better mechanistic understanding of how female state affects female mate-choice behavior can produce testable predictions and provide a basis for investigating the evolution of mating systems.     

Comparative study of the olfactory epithelium of the three-spined stickleback (Gasterosteus aculeatus) and the nine-spined stickleback (Pungitius pungitius)

Summary The olfactory epithelium of the three-spined stickleback (Gasterosteus aculeatus) and the nine-spined stickleback (Pungitius pungitius) has been studied with a conventional histochemical and a novel immunological staining technique. In both species, the sensory epithelium is arranged in folds separated by non-sensory epithelial tissue. In the nine-spined stickleback, intrinsic folds consisting of non-sensory cells are found in the apical part of the sensory epithelium where they divide the surface of the sensory epithelium into small islets. These non-sensory cells are non-ciliated, flattened and piled on top of each other; they contain numerous electron-translucent vesicles. The intrinsic folds are absent from the sensory epithelium of the three-spined stickleback. In both species, axons of receptor cells form a layer of fibers in the sensory epithelium immediately above the basal cells. In the three-spined stickleback, thick branches of the olfactory nerve are frequently found in this layer. These branches are only occasionally observed in the sensory epithelium of the nine-spined stickleback. Thus, the three-spined stickleback and the nine-spined stickleback show considerable differences in the organization of the sensory regions of the olfactory epithelium.     

Complete mitochondrial genome of the Antarctic amphipod Gondogeneia antarctica (Crustacea, amphipod)

The complete sequence of the mitochondrial genome of the Antarctic amphipod Gondogeneia antarctica was determined to be 18,424 bp in length, and to contain 13 protein-coding genes (PCGs), 22 tRNA genes, and large (rrnL) and small (rrnS) rRNA genes. Its total A+T content is 70.1%. The G. antarctica mitogenome is the largest known among those of crustaceans, due to the existence of two relatively large intergenic non-coding sequences. The PCG arrangement of G. antarctica is identical to that of the ancestral pancrustacean ground pattern, although the tRNA arrangement differs somewhat. The complete mitogenome sequences of 68 species of pancrustacea have been added to the NCBI database, only 4 of which represent complete mitogenome sequences from amphipods. This is the first report of a mitogenome sequence of an Antarctic amphipod, and provides insights into the evolution of crustacean mitochondrial genomes, particularly in amphipods.     

Complete mitochondrial genome of the longtooth grouper Epinephelus bruneus (Perciformes, Serranidae)

We determined the complete nucleotide sequence of the mitochondrial (mt) genome for the longtooth grouper, Epinephelus bruneus (Perciformes, Serranidae). This mt genome, consisting of 16,686 base pairs (bp), encoded genes for 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a noncoding control region as those found in other vertebrates, with the gene order identical to that of typical vertebrates. A major noncoding region between the trnP and trnF genes (991 bp) was considered to be the control region (D-loop). Within this sequence, 22 copies of a 17-bp tandem repeat element, 5'-TGATATTACATATATGC-3', were identified in the control region unlike previous reported Epinephelus species.     

Complete mitochondrial genome of the jackknife clam Solen grandis (Veneroida, Solenidae)

The complete mitochondrial genome sequence of Solen grandis that lives in sub-tidal waters and being buried in muddy to fine sand substrates, is described in this paper. The mitogenome (16,794?bp) consists of 12 protein-coding genes (loss of ATPase subunit 8), 22 tRNA genes, 2 rRNA genes and 1 putative control region. It is the typical bivalve mitochondrial gene composition.     

Complete mitochondrial genome of the marine medaka Oryzias melastigma (Beloniformes, Adrianichthyidae)

The complete mitochondrial genome was obtained from the assembled genome data sequenced by next-generation sequencer from the marine medaka Oryzias melastigma. The mitochondrial genome sequence was 16,864 bp in size, and the gene order and contents were identical with those of previously reported fish mitochondrial genomes. Of 13 protein-coding genes (PCGs), 4 genes (CO3, ND3, ND4, and Cytb) had incomplete stop codons. The base composition of O. melastigma mitogenome showed high A+T (59.65%) and anti-G bias (8.73%) on the 3rd position of PCGs.     

Complete mitochondrial genome of the Walking goby Scartelaos histophorus (Perceformes, Gobiidae)

The Walking goby Scartelaos histophorus (Perciformes, Gobiidae) is an amphibious gobioid fish. In this paper, the complete mitochondrial genome of S. histophorus was first determined. The genome is 16,496 bp in length and consists of 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes, and 1 control region. The overall base composition of S. histophorus is 27.5% for T, 28.0% for C, 28.3% for A, and 16.1% for G, with a slight A+T bias of 55.8%. It has the typical vertebrate mitochondrial gene arrangement.     

Complete mitochondrial genome of black porgy Acanthopagrus schlegelii (Perciformes, Sparidae)

Black porgy, Acanthopagrus schlegelii, is a marine protandrous hermaphrodite and belongs to one of the most important species commercialized for food in various areas of Asia. In this study, the complete mitochondrial genome of A. schlegelii has been determined. The mitogenome was 16,649 bp in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 2 non-coding regions. It shared 90.2%, 82.3%, and 82.1% mitogenome sequence with Acanthopagrus latus, Parargyrops edita, and Pagrus major, respectively.