A new species of the genus Tegastes (Copepoda: Harpacticoida: Tegastidae) from hydrothermal vents in the Okinawa Trough.

Back, Jinwook,Huys, Rony,Lee, Wonchoel Zoological Society of Japan 2010 Zoological science Vol.27 No.8

<P>We describe a new species, Tegastes okinawaensis, from 583-711 meter-deep hydrothermal vents in the Okinawa Trough, Japan. This species is clearly distinguishable from its congeners by four combined characters, namely 1) the last three abdominal somites are depressed inwardly towards the body, 2) there is sexual dimorphism in the number of setae of P3 and P4, 3) the male antennule is 9-segmented, with the 7th segment formed by incomplete fusion of two segments, and 4) the caudal rami are small with a distorted quadrangular shape. Additionally, the species is easily distinguishable from its congeners by the distal endopodal segment of P4, which is armed with six setae - this character has never been reported in previous descriptions of congeners. This report is the first of a species in the genus Tegastes living at ocean depths of greater than 580 m in the northwestern Pacific.</P>

Effects of Endocrine Disruptors on Bombina orientalis P450 Aromatase Activity.

Lee, Kyung-Min,Yang, Wonseok,Rhee, Jae-Sung,Hwang, Dae-Sik,Jin Park, Chan,Chan Gye, Myung,Lee, Jae-Seong,Shin, Incheol Zoological Society of Japan 2010 Zoological science Vol.27 No.4

<P>To assess the effects of endocrine-disrupting chemicals on the expression and activity of aromatase in the gonads of Bombina orientalis, a common amphibian, we intraperitoneally injected nonylphenol or bisphenol-A and then examined aromatase mRNA levels by RT-PCR as well as aromatase enzymatic activity by tritiated water release assays. To design primers for the RT-PCR, we cloned the B. orientalis aromatase gene using RT-PCR and degenerate primers. The full-length cDNA was obtained by 5'- and 3'-RACE PCR. The complete sequence of the B. orientalis aromatase gene revealed an open reading frame of 1500 bp encoding a deduced protein of 500 amino acids. Semi-quantitative RT-PCR indicated that nonylphenol or bisphenol-A injection did not significantly affect the expression of B. orientalis aromatase mRNA. However, a 48-hr treatment with nonyphenol or bisphenol A reduced aromatase activity to 47% and 32% of the control, respectively. These results suggest that endocrine disrupters can effectively modulate the activity of B. orientalis aromatase without affecting its mRNA levels.</P>

Characterization of a Sea Urchin IQ Motif Containing Protein D as a Coactivator of Nuclear Receptors

Kim, M. A.,Sohn, Y. C. Zoological Society of Japan 2017 Zoological science Vol.34 No.3

<P>Nuclear receptor (NR) interacting proteins, such as coactivators and corepressors, play a crucial role in specifying the transcriptional activity of the receptor. However, little is known about the functional features of the NR coregulators in marine invertebrates. Using the yeast two-hybrid screening method, a sea urchin oocyte cDNA library was screened for proteins that interact with the ligand-binding domain of human RXR alpha (hRXR alpha) as the bait protein in the presence of 9-cis retinoic acid. Here, we describe IQ motif containing protein D (IQCD) as an RXR-interacting coactivator. The open reading frame of Strongylocentrotus nudus IQCD (SnIQCD) cDNA contains 1464 bp encoding a protein of 487 amino acids. SnIQCD and the vertebrate IQCDs contain well-conserved C-terminal IQ motifs and coiled-coil domains. The interactions between RXR alpha and IQCD were confirmed by an immunoprecipitation assay and a mammal two-hybrid assay. RXR alpha preferentially interacted with the C-terminal half including IQ motif than the N-terminal half of SnIQCD. The coactivator interacting LXXLL motif in SnIQCD is not directly involved in the interaction with RXR alpha. SnIQCD overexpression increased the basal RXR transactivation of a RXR-responsive reporter gene. Furthermore, SnIQCD enhanced the transcriptional activity of RXR heterodimeric partners such as RAR, PPAR, and the steroid hormone receptor family members from mammals, teleost fish, and sea urchin. Taken together, we suggest that IQCD orthologs are able to function as transcriptional coactivators cooperating with NRs.</P>

Phylogenetic Relationships of Dorcus koreanus Jang and Kawai, 2008 (Coleoptera, Lucanidae): Species or Subspecies?

Han, Tae Man,Jeong, Jong Chel,Kang, Tae Hwa,Lee, Young Bo,Park, Hae Chul Zoological Society of Japan 2010 Zoological science Vol.27 No.4

<P>Dorcus koreanus Jang and Kawai, 2008 was recently described as a valid species in Haenam, South Korea, based on morphology. However, the taxonomic position and relationships of this new species with the related species Dorcus japonicus and Dorcus carinulatus were not examined in detail. To address this issue, we evaluated the phylogenetic relationships of D. koreanus to its related species based on molecular analyses of mitochondrial 16S rRNA gene sequences. The molecular evidence suggested that D. koreanus and D. carinulatus are more closely related to each other than either is to D. Japonicus. The genetic divergence between D. koreanus and D. carinulatus ranged from 1.2 to 1.6%, whereas that between D. koreanus and D. japonicus ranged from 9.0 to 9.2%. By comparing the range of nucleotide substitutions within Lucanidae, we determined that the sequence distance between D. koreanus and D. carinulatus is smaller than that for required for species-level distinction. Therefore, we reduce D. koreanus to subspecies rank, as Dorcus carinulatus koreanus stat. nov.</P>

Effects of shortened photoperiod on gonadotropin-releasing hormone, gonadotropin, and vitellogenin gene expression associated with ovarian maturation in rainbow trout.

Choi, Sungchang,Lee, Cheul Ho,Park, Woodong,Kim, Dae-Jung,Sohn, Young Chang Zoological Society of Japan 2010 Zoological science Vol.27 No.1

<P>Reproductive activities of salmonids are synchronized by changes in photoperiod, which control the endocrine system via the brain-pituitary-gonadal axis. Gonadotropin-releasing hormone (GnRH) in the brain regulates synthesis and release of the pituitary gonadotropins (GTHs; FSH and LH). FSH and LH in turn stimulate the production of sex steroids for oocyte growth and maturation-Inducing steroid hormones for oocyte maturation and ovulation, respectively, in female salmonids. To clarify effects of long-term photoperiod manipulations on the reproductive activity of salmonids from early recrudescence to ovulation, we Investigated the gene expression profiles of GnRH, GTHs, and vitellogenin (VTG), and plasma sex steroids in female rainbow trout (Oncorhynchus mykiss). In addition, the percentages of eyed embryos and hatched alevins were examined together with the number of ovulated eggs to evaluate the effects of photoperiod regimes on egg quality. During late summer, the mRNA levels of GnRHs, GTHalpha, and LHbeta, and the plasma level of a maturational steroid (17alpha,20beta-dihydroxy-4-pregnen-3-one; 17,20beta-P) were significantly elevated by a gradually shortened photoperiod under constant temperature, in accordance with accelerated sexual maturation. The percentages of eyed embryos and hatched alevins from fish ovulated in August were comparable to those of control fish observed in December. These results clearly indicate that syntheses of GnRHs, LH, VTG, and 17,20beta-P are effectively accelerated by a programmed long-short photoperiod regime in early recrudescent female rainbow trout, without a marked deterioration in egg quality.</P>

(Original Articles) Molecular Cloning of Stanniocalcin 1 and Its Extracorpuscular Regulation by Salinity and Ca²⁺ in the Japanese Flounder

Shin, Jihye,Sohn, Young Chang Zoological Society of Japan 2008 Zoological science Vol.25 No.7

Stanniocalcin 1 (Stc1) was originally identified as an anti-hypercalcemic hormone produced by the corpuscles of Stannius (CS) associated with the kidney in teleosts. While the stc1 gene is expressed in various tissues in fishes, its role and regulation in extra-CS tissues are unexplored. In the present study, we characterized a cDNA of stc1 in a euryhaline fish, the Japanese flounder (Paralichyhus olivaceus), and examined its expression in peripheral tissues in response to different salinities and Ca<SUP>2+</SUP> ion concentrations. The Japanese flounder stc1 cDNA (1331 bp) encodes a preprohormone of 251 amino acids (aa), with a signal peptide of 17 aa and a pro-sequence peptide of 15 aa followed by the mature protein of 219 aa. The deduced aa sequence of Japanese flounder stc1 showed highest sequence identity (94.0%) with the European flounder Stc1 among fish and mammalian species, but lower identity to zebrafish, pufferfish, and human STC2 (23.1?25.4%). Lowered environmental salinity resulted in a decrease in stc1 mRNA expression in vivo in the gills, kidney, intestine, and CS glands of the Japanese flounder. Furthermore, we found that extracellular Ca<SUP>2+</SUP> increased steady-state stc1 mRNA levels in gill and kidney cells as well as in the CS cells. Our findings suggest that Stc1 synthesis in the ionregulatory tissues is responsive to environmental salinity and Ca<SUP>2+</SUP> level.

Effects of Weather Factors on the Abundance and Diversity of Moths in a Temperate Deciduous Mixed Forest of Korea

Zoological Society of Japan 2008 Zoological science Vol.25 No.1

Three-year (2004?2006) monitoring results of macrolepidoptera using light traps in a temperate deciduous mixed forest were analyzed to investigate the relationship between moth diversity and nine weather variables. Results of stepwise regression analyses showed that mean daily temperature was the main predictor for moth diversity. The present study also revealed that each moth family was affected by a set of different weather factors (rainfall, relative humidity, or duration of sunshine) probably due to different life-history strategies. The impacts of recent climate change on insect populations may be evidenced in the close relationship between moth abundance and mean temperature.

Genomic Structure and Expression Analyses of the PYGM Gene in the Thoroughbred Horse.

Nam, Gyu-Hwi,Ahn, Kung,Bae, Jin-Han,Han, Kyudong,Lee, Chong-Eon,Park, Kyung-Do,Lee, Sang-Hak,Cho, Byung-Wook,Kim, Heui-Soo Zoological Society of Japan 2011 Zoological science Vol.28 No.4

<P>Muscle glycogen Phosphorylase (PYGM) has been shown to catalyze the degradation of glycogen to glucose-1-phosphate. The PYGM gene can contribute to providing energy to the body by disassembling the glycogen in muscle. Here, we analyzed the genomic structure and expression of the PYGM gene in the thoroughbred horse. The PYGM gene, containing several transposable elements (MIRs, LINEs, and MERs), was highly conserved in mammalian genomes. In order to understand the expression of the horse PYGM gene, we performed quantitative RT-PCR using 11 thoroughbred horse tissue samples. The horse PYGM gene was broadly expressed in all tissues tested. In particular, the highest expression of the horse PYGM gene was observed in skeletal muscle tissue relative to the other tissues. Interestingly, the horse PYGM gene contains fewer mobile elements than its human ortholog, resulting in an increase in the structural stability of the PYGM gene sequence. This study provides insights into the genomic structure of the horse PYGM gene that may be useful in future studies of its association with exercise capability.</P>

DNA Sexing of Nipponia nippon by Duplex Polymerase Chain Reaction

Park, J.Y.,Lee, J.H.,Choi, S.A.,Kim, K.J.,Lee, I.B.,Kim, M.K. Zoological Society of Japan 2011 Zoological science Vol.28 No.10

Molecular Characterization of Alternative Transcripts of the Horse BMAL1 Gene

Bae, J.-H.,Ahn, K.,Nam, G.-H.,Lee, C.-E.,Park, K.-D.,Lee, H.-K.,Cho, B.-W.,Kim, H.-S. Zoological Society of Japan 2011 Zoological science Vol.28 No.9